IPAC2011 - List of Keywords (storage-ring)

Paper	Title	Other Keywords	Page
MOXAA01	ALBA Synchrotron Light Source Commissioning	booster, linac, synchrotron, injection	1
	D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	ALBA is a 3rd generation Synchrotron Light Source build in Barcelona, Spain. It is a 3 GeV Light Source with a circumference of roughly 270 m, an emittance of 4.4 nmrad and a design current of 400 mA. The storage ring has 24 straight sections from which 19 can be used for the installation of insertion devices, the rest will be used for injection, RF-cavities and diagnostic. The storage ring has been optimized for a high photon flux density for the users. The 3 GeV booster synchrotron with an emittance smaller the 10 nmrad is installed in the same tunnel. The pre injector is a 100 MeV Linac. The project started officially in 2004. The linac is operating since 2008, the booster since 2010 and the first commissioning phase for the storage ring will be finished in June 2011. This presentation gives an overview of the ALBA project with the emphasis on the results of the commissioning of the three accelerators Linac, booster synchrotron and storage ring.
	Slides MOXAA01 [8.891 MB]

MOPC004	352.2 MHz HOM Damped Normal Conducting ESRF Cavity: Design and Fabrication	cavity, HOM, coupling, vacuum	68
	V. Serrière, A.K. Bandyopadhyay, D. Boilot, L. Goirand, J. Jacob, B. Ogier, A. Triantafyllou ESRF, Grenoble, France
	Funding: This work, carried out within the framework of the ESRFUP project, has received research funding from the EU Seventh Framework Programme, FP7. The ongoing ESRF upgrade included an option for an increase of the storage ring current from 200 to 300 mA, which has been tested successfully with the existing RF system. At this current level the HOM tuning of the existing five-cell copper cavities becomes extremely delicate and in view of a future reliable operation in user mode, new HOM free normal conducting cavities were developed at the ESRF. The design is based on the existing BESSY/ALBA cavity. However, several substantial modifications have been implemented and different fabrication processes elaborated to improve the design. Three operational prototypes will be delivered by three manufacturers in the coming months and will be fully tested on the ring. Although the 300 mA option has finally not been retained for the first phase of the ESRF upgrade, the aim is now to validate the new cavity design for a possible later increase in current.

MOPC045	Commissioning of the ALBA Storage Ring RF System	cavity, LLRF, HOM, pick-up	178
	F. Pérez, B. Bravo, A. Salom, P. Sanchez CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	ALBA is a 3 GeV, 400 mA, 3rd generation Synchrotron Light Source that is under commissioning in Cerdanyola, Spain. The RF System has to provide 3.6 MV of accelerating voltage and restore up to 540 kW of power to the electron beam. For that six RF plants, working at 500 MHz, are foreseen. The RF plants include several new developments: DAMPY cavity; the normal conducting HOM damped cavity developed by BESSY and based in the EU design; six are installed. CaCo; a cavity combiner to add the power of two 80 kW IOTs to produce the 160 kW needed for each cavity. WATRAX; a waveguide transition to coaxial, specially designed to feed the DAMPY cavities due to the geometrical and cooling constrains. Digital LLRF; fully designed at ALBA using commercial components. This paper shortly describes these systems and reports their performance during the ALBA commissioning.

MOPC046	CaCo: A Cavity Combiner for IOTs Amplifiers	cavity, simulation, high-voltage, HOM	181
	B. Bravo, F. Mares, F. Pérez, P. Sanchez CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain M.L. Langlois ESRF, Grenoble, France
	The ALBA storage ring uses six room temperature cavities; each one fed by two 80 kW IOTs amplifiers at 499.654 MHz. The power of the pair of transmitters is combined by a cavity combiner, CaCo. One of the design requirements of CaCo was that it continued working safely and with a good efficiency in the case of an IOT failure (asymmetrical mode). During the first asymmetric full power tests, in May 2010, with an active IOT and the other passive, the result was dramatic, the passive IOT broke in two parts after few hours of operation. This paper presents the experimental results and the electromagnetic field simulations of the asymmetrical operation mode of CaCo, i.e. one active IOT and the other passive, and analyze why the ceramic of the output tube of the passive IOT broke during the first performance of this mode. Also, it reports a possible solution to solve this problem.

MOPC051	The 100 MHz RF System for the MAX IV Storage Rings	cavity, LLRF, HOM, impedance	193
	Å. Andersson, E. Elafifi, M. Eriksson, D. Kumbaro, P. Lilja, L. Malmgren, R. Nilsson, H. Svensson, P.F. Tavares MAX-lab, Lund, Sweden J.H. Hottenbacher RI Research Instruments GmbH, Bergisch Gladbach, Germany A. Milan CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain A. Salom ELETTRA, Basovizza, Italy
	The construction of the MAX IV facility has started and user operation is scheduled to commence 2015. The facility is comprised of two storage rings optimized for different wavelength ranges, and a linac-based short pulse facility. In this paper the RF systems for the two storage rings are described. The RF systems will be based on either tetrode or solid state amplifiers working at 100 MHz. Circulators will be used to give isolation between cavity and power amplifier. The main cavities are of normal conducting, entire copper, capacity loaded type, where the present cavities at MAX-lab has served as prototypes. For the MAX IV ring operation it is essential to elongate bunches, in order to minimize the influence of intra beam scattering on beam transverse emittances. For this, 3rd harmonic passive (Landau-) cavities are employed. These are of similar type as the main cavities, mainly because the capacity loaded type has the advantage of pushing higher order modes to relatively high frequencies compared to pill-box cavities. Digital low level RF systems will be used, bearing in mind the possibility of post mortem analysis.

MOPC078	Operation of Superconducting Cavities in a Fast Ramping Electron Storage Ring	cavity, HOM, impedance, acceleration	253
	A. Roth, W. Hillert ELSA, Bonn, Germany
	Funding: Supported by German Research Foundation through SFB/TR 16. The achievable maximum energy of a medium-sized electron accelerator is mainly limited by the accelerating voltage. Using superconducting (sc) cavities, the energy limitation can be shifted considerably. However, the operation of sc multi-cell cavities in a fast ramping storage ring causes additional problems which were investigated at the 3.5 GeV Electron Stretcher Accelerator ELSA. We studied the use of two 500 MHz sc cavities providing the necessary resonator voltage of up to 14 MV and replacing the normal conducting cavities of PETRA type. A large cavity coupling factor is required, so that using the existing 250 kW klystron, an internal beam of 50 mA can be accelerated up to 5 GeV. In addition, a fast detuning of the resonance frequency of the cavities must be implemented during beam injection and the energy ramp of 4 GeV/s. An appropriate 500 MHz structure is given by a five-cell cavity constructed for the JAERI-FEL-LINAC. Based on this geometry, HOM have been calculated from a numerical simulation. Since all monopole and a larger number of dipole HOM are well above the multibunch instabilities threshold, further studies about beam instabilities damping are essential.

MOPC127	Development of High RF Power Solid State Amplifiers at SOLEIL	cavity, power-supply, booster, klystron	376
	P. Marchand, M.E. El Ajjouri, R. Lopes, F. Ribeiro, T. Ruan SOLEIL, Gif-sur-Yvette, France
	In SOLEIL, 5 solid state amplifiers provide the required 352 MHz RF power: 1 x 35 kW for the booster (BO) cavity and 4 x 190 kW for the 4 superconducting cavities of the storage ring (SR). Based on a design fully developed in house, they consist in a combination of a large number of 330W elementary modules (1 x 147 in the BO and 4 x 724 in the SR) with MOSFET transistors, integrated circulators and individual power supplies. After 5 years of operation, this innovative design has proved itself and demonstrated that it was an attractive alternative to the vacuum tube amplifiers, featuring an outstanding reliability and a MTBF > 1 year. In the meantime, thanks to the acquired expertise and the arrival of the 6th generation transistors, SOLEIL has carried out developments which led to doubling the power of the elementary module (700 W at 352 MHz and 500 MHz), while improving the performance in terms of gain, efficiency and thermal stress. This approach was also extended to frequencies from the FM to L band. The increasing interest for this technology has led SOLEIL to collaborate with several other laboratories and conclude a transfer of know-how with the French company, ELTA-AREVA.

MOPC130	High Power Solid State RF Amplifier Proposal for Iran Light Source Facility (ILSF)	cavity, booster, rf-amplifier, simulation	385
	R. safian IPM, Tehran, Iran M. Jafarzadeh ILSF, Tehran, Iran
	Solid state RF amplifiers are being considered for an increasing number of accelerator applications. Their capabilities extend from a few kW of power to several hundred kilo watts and from frequencies less than 100 MHz to above 1 GHz. This paper describes the proposed general scheme for the high power solid state RF generator of the Iran light source facility (ILSF). The maximum expected power of the generator is 200 KW which is used for driving the storage ring cavities. Similar RF generator with lower output power can be used for driving the booster cavities.

MOPO002	Fast Orbit Correction for the ESRF Storage Ring	power-supply, feedback, diagnostics, controls	478
	E. Plouviez, F. Epaud, J.M. Koch, K.B. Scheidt ESRF, Grenoble, France
	Today, at the ESRF, the correction of the orbit position is performed with two independent systems: one to deal with the slow movements and one to correct the motion in a range of up to 200Hz but with a limited number of fast BPMs and steerers. This later will be removed and one unique system will cover the frequency range from DC to 200Hz using all the 224 BPMs and the 96 steerers. Indeed, thanks to the procurement of the Liberas Brilliance and installation of new AC power supplies, it is now possible to access all the Beam positions at a frequency of 10 kHz and to drive a small current in the steerers in a 400Hz bandwidth. The first tests of correction of the beam position have been performed and will be presented. This new orbit correction system is also a powerful diagnostics system: the measurement and survey of the Ring's lattice parameters is possible thanks to the high measurement rate of very high resolution position data. Results of this will also be presented.

MOPO010	Orbit Feedback System for the MAX IV 3 GeV Storage Ring	feedback, vacuum, power-supply, simulation	499
	M. Sjöström, J. Ahlbäck, M.A.G. Johansson, S.C. Leemann, R. Nilsson MAX-lab, Lund, Sweden
	The paper describes the current orbit correction system design for the 3 GeV storage ring at the MAX IV laboratory, a light source facility under construction in Lund, Sweden. The orbit stability requirements for the 3 GeV storage ring are tight at roughly 200 nm vertical position stability in the insertion device (ID) straight sections. To meet this the ring will be equipped with 200 beam position monitors (BPMs) and 380 dipole corrector magnets, 200 in the horizontal and 180 in the vertical plane. The feedback loop solution, one slow orbit feedback (SOFB) loop and one fast orbit feedback (FOFB) loop in fast acquisition mode at 10,000 samples/second, will be presented. The paper will also discuss the various boundary conditions specific to the MAX IV 3 GeV storage ring design, such as a Cu vacuum chamber, and the impact on the corrector design.

MOPO035	Stability of the Floor Slab at Diamond Light Source	site, insertion, insertion-device, target	562
	J. Kay, K.A.R. Baker, W.J. Hoffman Diamond, Oxfordshire, United Kingdom I.P.S. Martin JAI, Oxford, United Kingdom
	A Hydrostatic Leveling System (HLS) has been installed at Diamond Light Source. 8 sensors have been positioned along a 60 metre portion of the floor of the Storage Ring and the Experimental Hall, stretching out along a typical beamline route from Insertion Device to sample. Results since June 2008 are presented comparing actual performance with the original specification as well as identifying movements associated with environmental factors.

MOPS007	Interference of CSR Fields in a Curved Waveguide	impedance, positron, damping, wakefield	604
	D.M. Zhou, K. Ohmi KEK, Ibaraki, Japan
	CSR fields generated by a bunched beam passing through a series of bending magnets may interfere with each other due the reflections of outer chamber wall. This kind of multi-bend interference causes sharp peaks and long-range tail in the CSR impedance and wake potentials, respectively. Using a dedicated computer code, CSRZ, we calculated the longitudinal CSR impedance in the SuperKEKB positron damping ring for purpose of demonstration. It was found that multi-bend interference may enhance the CSR fields within a distance comparable to the bunch length, which is typically in the order of several millimeters. A simple instability analysis was performed and it suggested that multi-bend interference might play a role in the single-bunch instabilities of small electron/positron rings.

MOPS048	Microbunching Instability Studies at SOLEIL	electron, radiation, synchrotron, synchrotron-radiation	709
	C. Evain, J. Barros, J.B. Brubach, L. Cassinari, M.-E. Couprie, G. Creff, M. Labat, A. Loulergue, L. Manceron, R. Nagaoka, P. Roy, M.-A. Tordeux SOLEIL, Gif-sur-Yvette, France
	Microbunching instability arises in storage rings when the number of electrons in a bunch exceeds a threshold value. Its signature, i.e. a strong and irregular emission of Coherent Synchrotron Radiation (CSR) in the Terahertz (THz) domain, is studied at SOLEIL on the AILES infrared beamline, with the storage ring tuned in a low-alpha configuration (used to get shorter electron bunch). The comparison of this observed THz CSR with numerical simulations of the longitudinal electron bunch dynamics, permits to put in evidence that during the instability a modulation appears and drifts in the longitudinal profile of the electron bunch. The understanding of this instability is important as it limits some operation of the storage rings. Indeed the induced fluctuations prevent the use of THz on the far IR beamline at high current per bunch. And in normal alpha operation this instability may spoil the electron/laser interaction effects used to get femtosecond and/or coherent pulse in storage rings (with slicing, Coherent Harmonic Generation or EEHG schemes on storage ring).

MOPS056	An Analytical Formula of the Electron Cloud Linear Map Coefficient in a Strong Dipole	electron, dipole, vacuum, simulation	733
	T. Demma INFN/LNF, Frascati (Roma), Italy S. Petracca, A. Stabile U. Sannio, Benevento, Italy G. Rumolo CERN, Geneva, Switzerland
	Electron cloud effects have been indentified as one of the most serious bottleneck for reaching design performances in presently running and proposed future storage rings. The analysis of these effects is usually performed with very time consuming simulation codes. An alternative analytic approach, based on a cubic map model for the bunch-to-bunch evolution of the electron cloud density, could be useful to determine regions in parameters space compatible with safe machine operations. In this communication we derive a simple approximate formula relating the quadratic coefficient in the electron cloud density map to the parameters relevant for the electron cloud evolution in a strong vertical magnetic field. Results are compared with simulations with particular reference to the LHC dipoles.

MOPS065	Transverse Instability Studies at the ALBA Storage Ring	impedance, vacuum, single-bunch, kicker	751
	T.F. Günzel CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	In the first phase of the ALBA storage ring operation 3 NEG-coated aluminum chambers, 2 in-vacuum undulators and one wiggler chamber will be installed. Under particular consideration of the multilayer character of these chambers and the injection kickers the thresholds of the transverse mode coupled instability(TMCI) were calculated using MOSES. The thresholds 17.5mA/40.5mA vertical/horizontal leave a rather large operative margin. The detrimental effect of the NEG-coating on the TMCI is relatively limited and on the resistive wall instability is even negligible. As well the thresholds of the head-tail instability were computed as function of chromaticity. Also the incoherent tune shifts generated by the quadrupolar resistive wall wake fields due to the flatness of the vacuum chambers were calculated. The computed results have been compared to first measurements of the storage ring commissioning. Y.H.Chin, MOSES 2.0, CERN/LEP-TH/88-05

MOPS066	Collective Effects in the MAX IV 3 GeV Ring	impedance, cavity, damping, synchrotron	754
	P.F. Tavares MAX-lab, Lund, Sweden T.F. Günzel CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain R. Nagaoka SOLEIL, Gif-sur-Yvette, France
	We present calculations of collective instability effects in the 3 GeV electron storage ring of the MAX IV facility currently under construction in Lund, Sweden. The storage ring is designed to deliver ultra-low emittance down to 0.24 nm rad so as to provide high brightness synchrotron radiation from undulators. This is achieved in a comparatively small machine (528 m circumference) through the use of a multi-bend achromat lattice and a compact magnet design featuring multi-purpose narrow gap magnet blocks. This design features small dispersion leading to low momentum compaction, which, together with the small circular (11 mm radius) chambers, poses a challenge to reach the design current (500 mA in 176 bunches) without exciting instabilities and degrading beam parameters due to the interaction with the machine impedance. Particularly important are multi-bunch resistive wall effects in the NEG coated copper chamber as well single-bunch instabilities driven by the broad-band impedance. A low RF frequency (100 MHz) and harmonic cavities are foreseen to lengthen the bunches and increase instability thresholds.

MOPZ012	The International Design Study for the Neutrino Factory	factory, target, proton, cavity	847
	J.K. Pozimski, A. Kurup, K.R. Long Imperial College of Science and Technology, Department of Physics, London, United Kingdom J.S. Berg BNL, Upton, Long Island, New York, USA
	The International Design Study for the Neutrino Factory (the IDS-NF) has recently completed the Interim Design Report* (IDR) for the facility as a step on the way to the Reference Design Report (RDR). The IDR has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents the present baseline design for the facility which will provide 10²¹ muon decays per year from 25 GeV stored muon beams. The facility will serve two neutrino detectors; one situated at source-detector distance of between 3000–5000 km, the second at 7000–8000 km. The conceptual design of the accelerator facility will be described and its performance will be presented. The steps that the IDS-NF collaboration has taken since the IDR was finalized and plans to take to prepare the RDR will also be presented. * IDS-NF-020: https://www.ids-nf.org/wiki/FrontPage/Documentation?action=AttachFile&do=get&target=IDS-NF-020-v1.0.pdf Submitted on behalf of the IDS-NF collaboration

TUODA01	Vertical Emittance Reduction and Preservation at the ESRF Electron Storage Ring	emittance, coupling, quadrupole, feedback	928
	A. Franchi, J. Chavanne, F. Ewald, L. Farvacque, T.P. Perron, K.B. Scheidt ESRF, Grenoble, France
	In 2010 a campaign for the reduction and preservation of low vertical emittance at the ESRF electron storage ring was undertaken: values between 20 and 30 pm have been dramatically reduced to 3.5-4.5 pm, even during beam delivery. This improvement is the result of an increased measurement precision provided by the recently upgraded beam position monitoring system, a new correction algorithm, a larger number of correctors and two independent schemes for the automatic compensation of coupling induced by a few insertion devices whenever their gaps are moved by users during beam delivery. This paper summarizes the campaign's milestones and the results updated to the first half of 2011.
	Slides TUODA01 [5.297 MB]

TUXB01	Methods and Tools to Simulate and Analyse Non-linear Dynamics in Electron Storage Rings	lattice, emittance, sextupole, quadrupole	937
	L.S. Nadolski SOLEIL, Gif-sur-Yvette, France
	This talk will present the different approaches and tools that have been recently developed while trying to understand or predict the non-linear dynamics of electron storage rings. Different algorithms have been recently used at different places to optimize the sextupole tunings, while the refinement of the models of existing machines together with more accurate measurement techniques enable now to fully understand the limitations of such facilities specially in the presence of insertion devices.
	Slides TUXB01 [7.624 MB]

TUOAB02	Simultaneous Long and Short Bunch Operation in an Electron Storage Ring - a Hybrid Mode based on Nonlinear Momentum Compaction	electron, synchrotron, octupole, photon	945
	M. Ries, J. Feikes, A. Jankowiak, P.O. Schmid, G. Wüstefeld HZB, Berlin, Germany
	The generation of short pulses in electron storage rings is driven by different user groups like time resolved x-ray spectroscopy users or users of coherent synchrotron radiation. The required optics and operation conditions to generate this short bunches are worsening the experimental conditions, e.g. strongly reducing the average photon flux, for the regular user. Therefore short bunch operation is usually limited to dedicated user shifts. By controlling higher orders of the momentum compaction factor by higher multipoles it is possible to introduce a hybrid mode and simultaneously supplying long and short bunches. The Metrology Light Source (MLS) has the means to control these higher orders, therefore it is an ideal machine to investiate the feasibility of such a hybrid mode. Tracking results and first measurements will be shown. D. Robin et al., Proc. of EPAC08, p. 2100-2102, Genoa, Italy (2008). ** J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011).
	Slides TUOAB02 [7.817 MB]

TUOAB03	Enlarging Dynamic and Momentum Aperture by Particle Swarm Optimization	lattice, sextupole, dynamic-aperture, simulation	948
	Z. Bai, W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Particle swarm optimization (PSO) is a computational intelligence algorithm for global optimization. Obtaining adequate dynamic and momentum aperture is crucial for high injection efficiency and long beam lifetime in low emittance electron storage rings. Different from nonlinear driving terms optimization, we have made direct optimization of dynamic and momentum aperture by PSO algorithm. It is critical to make a criterion for comparison of dynamic and momentum aperture tracking results in the direct optimization procedure. Thus, in this paper we first propose a quantitative criterion of dynamic aperture. Then we apply PSO to the optimization of chromatic and harmonic sextupoles to find the optimum sextupole settings for enlarging the dynamic aperture. Taking the momentum aperture into consideration, we make joint optimization of dynamic and momentum aperture. Also, the momentum aperture has its quantitative criterion. As an example of application, the dynamic and momentum aperture of an FBA lattice studied in the design of storage ring of Hefei Advanced Light Source were optimized, and the results have shown the power of PSO algorithm.
	Slides TUOAB03 [0.313 MB]

TUODB01	Progress of the Construction for the TPS Vacuum System	vacuum, photon, impedance, ion	976
	G.-Y. Hsiung, C.K. Chan, C.H. Chang, C.-C. Chang, C.L. Chen, C.M. Cheng, Y.T. Cheng, S-N. Hsu, H.P. Hsueh, I.T. Huang, T.Y. Lee, I.C. Sheng, L.H. Wu, H.Y. Yan, Y.C. Yang, C.S. huang NSRRC, Hsinchu, Taiwan J.-R. Chen National Tsing Hua University, Hsinchu, Taiwan
	Vacuum system for the 3 GeV Taiwan Photon Source (TPS) has been started the construction since 2010. The critical components such as the bellows and gate valves with rf-contact shielding, pulsed magnet kicker ceramic chambers, BPM, crotch absorbers, etc. have been manufactured and tested. Aluminum alloy (Al-) vacuum chambers for the arc-cells have been machined and undergoing the in-house welding. Mass production of the vacuum equipments including the ion gauges, ion pumps, NEG pumps, and gate valves, has been contracted out and partially delivering following the schedule of the cell assembling. Each cell, contains two short Al-straight chambers and two Al-bending chambers, has been started the assembling and on-site welding on the pre-aligned girders in clean room forming an one-piece vacuum vessel about 14 m in length following by the vacuum baking to the ultra-high vacuum. The conceptual design of the vacuum systems for the long straight sections, the concentric booster, and the transport lines, will be addressed. The progress of prototyping development and the status of construction for the TPS vacuum system will be described in this paper.
	Slides TUODB01 [35.595 MB]

TUPC040	Modified Lattice of the Compton X-ray Source NESTOR	lattice, electron, sextupole, focusing	1087
	A.Y. Zelinsky, P. Gladkikh, A.A. Kalamayko, I.M. Karnaukhov, A. Mytsykov, A.A. Shcherbakov NSC/KIPT, Kharkov, Ukraine
	NESTOR is Compton X-ray source that is under commissioning in NSC KIPT. One of the main parts of the facility is the middle energy storage ring (40-225 MeV). The storage ring has comprehensive lattice to provide low emittance, low beam size in the interaction point and big value of the energy acceptance. One of the NESTOR storage ring lattice feature is use of bending magnets of 0.5 m radius with combined focusing function. It leads to increasing of 3D magnetic field effects on electron beam dynamics. After NESTOR magnetic element manufacturing characteristics of element magnetic fields were measured and the effect of the real magnetic field distribution on beam dynamics was calculated. As a result, to provide project X-ray source characteristics the parameters of NESTOR storage ring lattice should be modified. The second reason for the lattice modification was the desire to increase the interaction point straight section length. The results of the beam dynamics simulation after lattice modification and optimization show that the storage ring will provide all project electron beam parameters. The results of the electron beam simulations are presented in the paper.

TUPC062	Electron Beam Energy Measurement at the Australian Synchrotron Storage Ring	electron, synchrotron, resonance, scattering	1138
	M.J. Boland ASCo, Clayton, Victoria, Australia H. Panopoulos, R.P. Rassool, K.P. Wootton The University of Melbourne, Melbourne, Australia
	The technique of resonant spin depolarization was used to precisely measure the electron beam energy in the storage ring at the Australian Synchrotron. A detector and data acquisition system dedicated to the measurement were developed. Using the system, the long term energy stability of the storage ring was monitored and a mechanical realignment of the ring was clearly seen in the energy data. Details of the parameters used to optimize the measurement are also discussed.

TUPC072	Accurate Electron Beam Size Measurement at the Metrology Light Source	electron, photon, radiation, polarization	1165
	R. Klein, G. Brandt, R. Thornagel PTB, Berlin, Germany J. Feikes, M. Ries, G. Wüstefeld HZB, Berlin, Germany
	For the operation of the Metrology Light Source (MLS), the dedicated electron storage ring of the Physikalisch-Technische Bundesanstalt (PTB), as the national primary radiation source standard from the near infrared to the vacuum ultraviolet spectral region, all storage ring parameters which are relevant for the calculation of the radiant intensity by the Schwinger equation have to be known absolutely with small uncertainties. For the measurement of the effective vertical electron beam size a Bragg polarimeter, operating at a photon energy of 1103 eV, has been designed and put into operation. This system also serves as a detection system for the image of the electron beam through a set of narrow slits. The results obtained with the new device are compared to those measured by an optical beam imaging system. R. Klein et al., Phys. Rev. ST-AB 11, 110701 (2008). ** C. Koschitzki et al., Proc. IPAC10, 894-896 (2010).

TUPC075	Diagnostic Devices for Beam Intensity Measurement at FAIR	ion, synchrotron, diagnostics, antiproton	1174
	M. Schwickert, T. Hoffmann, F. Kurian, H. Reeg GSI, Darmstadt, Germany R. Geithner, W. Vodel HIJ, Jena, Germany R. Neubert, P. Seidel FSU Jena, Jena, Germany
	Funding: Work supported by EU, DITANET, Project No. ITN-2008-215080. Precise determination of beam intensity is important for any accelerator facility. At FAIR, the Facility for Antiproton and Ion Research presently in the planning phase at GSI, the requirements set by beam intensities in the various accelerators, storage rings and transport lines differ significantly. A set of beam diagnostic instruments is foreseen to detect the large variety of ion beams ranging from less than 10⁴ antiprotons up to high intensity of 5·10¹¹ uranium ions. This contribution presents an overview of destined current measurement devices, both intercepting, like scintillators, ionization chambers or secondary electron monitors, and non-intercepting current-transformer type devices. Ongoing developments are discussed for non-intercepting devices, i.e. a dc current transformer with large dynamic range and a cryogenic current comparator, purpose-built for the detection of lowest beam intensities at FAIR.

TUPC082	Beam Current Measurements at the TSR Heidelberg	ion, pick-up, acceleration, electron	1195
	M. Grieser, S.T. Artikova, K. Blaum, F. Laux, J. Ullrich MPI-K, Heidelberg, Germany
	To conduct experiments using low energy ion beams at the TSR heavy ion storage ring, the beam deceleration process must be well understood. During deceleration of the beam the revolution frequency decreases, resulting in low current, which is difficult to measure with a common DC transformer. The number of particles in a bunch is determined by measuring the voltage signal in the time domain using a capacitive pick-up. If the ratio of bunch length and RF period does not change during the deceleration or acceleration, measuring the pick-up signal spectrum, where the signal is directly proportional to the number of particles in a bunch, is a more sensitive method. An alternative method is using a beam profile monitor (BPM) for determining the number of particles in the storage ring via ionization rate measurements of the residual gas. A summary of these different methods to determine the number of particles is presented.

TUPC085	Observation of Microwave Radiation using Low-cost Detectors at the ANKA Storage Ring	radiation, synchrotron, vacuum, optics	1203
	V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller, M.J. Nasse, N.J. Smale KIT, Karlsruhe, Germany F. Caspers CERN, Geneva, Switzerland P. Peier PSI, Villigen, Switzerland
	Funding: Work supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320 Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed because the waveguide cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: The accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths above the waveguide cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually used in standard TV-SAT-receivers and are very cheap. We determined the time response of LNBs to be below 100 ns. The sensitivity of LNBs is optimized to detect very low intensity "noise-like" signals.

TUPC086	A Setup for Single Shot Electro Optical Bunch Length Measurements at the ANKA Storage Ring	laser, electron, synchrotron, radiation	1206
	N. Hiller, E. Huttel, A.-S. Müller, A. Plech KIT, Karlsruhe, Germany F. Müller, P. Peier, V. Schlott PSI, Villigen, Switzerland
	Funding: Supported by the Initiative and Networking Fund of the Helmholtz Association under VH-NG-320. Sponsored by the German Federal Ministry of Education and Research under contract number 05K10VKC Single shot electro optical bunch length measurements, in particular using spectral decoding, are foreseen for the ANKA storage ring. This will allow to resolve fast changes of bunch deformation and structure during the low alpha operation (2-15 ps rms bunch length). This technique uses a chirped laser pulse to probe the field induced birefringence in an electro optical crystal. The laser pulse is then analyzed in a single shot spectrometer. To obtain the birefringence modulation one can either use the near field of the electron bunch (placing the crystal close to the electron bunch in the UHV system of the storage ring), or the far field (coherent synchrotron radiation in the THz range at a THz-/IR-Beamline). The laser needs to supply: sufficient tunability of pulse length, a wide spectrum to allow for a sub-ps resolution. Additionally it must provide a mode-locked operation synchronized to the bunch revolution clock. For this purpose, a mode locked Ytterbium fibre laser system which operates at 10³⁰ nm has been developed at the Paul-Scherrer Institute in Switzerland. We give an overview over the experimental set up in the ANKA storage ring and the status of the project.

TUPC087	Filling Pattern Measurements at the ANKA Storage Ring	photon, electron, single-bunch, synchrotron	1209
	B. Kehrer, N. Hiller, A. Hofmann, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale KIT, Karlsruhe, Germany
	For many accelerator physics studies, e.g. the investigation of coherent synchrotron radiation (CSR), a precise knowledge of the quantitative filling pattern (i.e. the number of electrons per bunch) is essential. This can be achieved by either using a linear detector (analog recording) or by employing the method of time-correlated single photon counting (TCSPC). At the ANKA storage ring both methods are in use. The analogue detection is based on the signal from a stripline or annular electrode, the TCSPC uses a Single Photon Avalanche Diode (SPAD). In this paper, we describe the experimental set-ups and present results of a comparison of the two techniques for single as well as for multi bunch filling patterns.

TUPC117	Embedded EPICS IOC Data Acquisition System for Beam Instability Research	betatron, feedback, wakefield, EPICS	1290
	N. Zhang, Y.B. Leng SSRF, Shanghai, People's Republic of China
	Funding: This research is supported by National Natural Science Fund(No.Y155131061). To be a part of beam diagnostics system in SSRF 3.5 GeV electron storage ring, a high performance oscilloscope is introduced to build a bunch by bunch data acquisition and processing dedicated system, which is mainly used to observe individual bunch position in transverse plane and bunch charge. By analysis of Betatron oscillation amplitude distribution and corresponding filling pattern, we hope to find phenomenon about multi-bunch Wakefield effect[1] on beam Betatron oscillation for beam instability research. The system is configured as a scope IOC, and integrated into the EPICS based control system. Application of this system and some data analysis results are also discussed in this paper.

TUPC154	Commissioning of the Detection System for a Supersonic Gas-jets Based Transverse Beam Profile Monitor	ion, extraction, simulation, electron	1392
	M. Putignano, D. Borrows, A. Intermite The University of Liverpool, Liverpool, United Kingdom M. Putignano, M.R.F. Siggel-King, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: Work supported by STFC, the EU under GA-ITN-215080, the Helmholtz Association and GSI under VH-NG-328. We present the commissioning results of the Micro-Channel-Plate (MCP) based, ion extraction and detection system currently in use for an experimental test stand aimed at demonstrating the operation of a least-interceptive transverse beam profile monitor based on a planar supersonic gas-jet. This monitoring design features least-interceptive operation under excellent vacuum conditions and provides fast acquisition of a fully bi-dimensional transverse profile. It bears application for ultra-low energy particle beams at future storage rings, but also for e.g. linacs at high currents and light source injectors. For instance, the Ultra-low energy Storage Ring (USR), part of the Facility for Antiproton and Ion Research (FAIR) in Germany will store antiprotons at energies of 20-300 keV. In this contribution, we report numerical simulations and experimental results obtained by calibration of the detection system with a low energy electron beam to demonstrate a 1 mm imaging resolution only limited by recoiling ion drift.

TUPC159	Energy Measurements with Resonant Spin Depolarisation at Diamond	electron, feedback, resonance, quadrupole	1404
	I.P.S. Martin, M. Apollonio, R.T. Fielder, G. Rehm Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	A precise knowledge of the electron beam energy is critical for the accurate determination of many light source parameters, such as momentum compaction factor, natural chromaticity, energy stability and undulator spectra. In common with other facilities, a method of energy measurement based on resonant spin depolarisation has been developed at Diamond. In this paper we report on progress towards storage ring characterisation using this method, as well as describing the diagnostics developments that have enabled these measurements to be made.

TUPC163	Experimental Results from Test Measurements with the USR Beam Position Monitoring System	pick-up, simulation, vacuum, alignment	1416
	J. Harasimowicz, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom J. Harasimowicz, I. Takov The University of Liverpool, Liverpool, United Kingdom
	Funding: Work supported by STFC, the EU under GA-ITN-215080, the Helmholtz Association and GSI under VH-NG-328. A diagonal-cut capacitive pick-up (PU) was optimised for monitoring slow (v < 0.025c), long (~1 m) bunches consisting of only about 10⁶ antiprotons at the future Ultra-low energy Storage Ring (USR). Ultra-low noise (0.5 nV/Hz⁰.5) FET pre-amplifiers are used to allow detection of the weak signals generated in the PU plates. The amplified signals are then digitized by a 16-bit, 200 MS/s ADC and processed in a digital manner. The following contribution presents the beam monitoring system as it was tested with a stretched-wire method and compares the measurements with the results from 3D electromagnetic simulations.

TUPC166	Accelerator R&D in the QUASAR Group	antiproton, extraction, ion, diagnostics	1425
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: Work supported by STFC, the EU under GA-PITN-215080, the Helmholtz Associations and GSI under VH-NG-328. Since its start in 2007, the QUASAR Group’s research activities have grown considerably: Whilst the research program towards an ultra-low energy storage ring (USR) at the future facility for low-energy antiproton and ion research (FLAIR) is still the main research focus, developments of beam diagnostics tools for accelerators and lights sources, investigations into superconducting linear accelerators and medical applications, including the potential use of antiproton beams for cancer therapy purposes, widen the Group’s activities and international collaboration considerably. An overview of the QUASAR Group’s research achievements in accelerator science and technology to date is given in this contribution.

TUPO010	An Innovative Lattice Design for a Compact Storage Ring	lattice, radiation, synchrotron, synchrotron-radiation	1467
	S. Sasaki, A. Miyamoto HSRC, Higashi-Hiroshima, Japan
	Funding: *This work is partially supported by Cooperative and Supporting Program for Researches and Educations in Universities sponsored by KEK. We propose a new concept of lattice design for a compact light source storage ring. In a ring with this new scheme, the electron beam may have extremely longer design orbit than that of a conventional ring. In this ring, a design orbit closes after completing multiple turns. The lattice for realizing this exotic beam orbit can be made by placing conventional accelerator components such as bending magnets, quadrupole magnets, RF cavity and so forth in an appropriate manner onto a projected torus knot in the horizontal orbit plane. Due to an extended closed orbit length, the ring with this type of lattice has larger maximum stored charge if operated in multiple-bunch mode, and has longer bunch-to-bunch interval if operated in a single-bunch mode. Also, essential for a storage ring as the synchrotron light source, a larger number of straight sections may accommodate with many insertion devices. In addition, this new scheme may provide advantages for designing a oscillator-type free electron laser and coherent radiation light source.

TUPO013	Development of Pulse Width Measurement Techniques in a Picosecond Range of Ultra-short Gamma Ray Pulses	laser, photon, electron, scattering	1473
	Y. Taira, M. Hosaka, K. Soda, N. Yamamoto Nagoya University, Nagoya, Japan M. Adachi, M. Katoh, H. Zen Sokendai - Okazaki, Okazaki, Aichi, Japan T. Tanikawa UVSOR, Okazaki, Japan
	Funding: This work was supported by Grants-in-Aid for Scientific Research from Japan Society for the Promotion of Science (JSPS). We are developing the ultra-short gamma ray pulse source with the energy of MeV region based on laser Compton scattering at the 750 MeV electron storage ring, UVSOR-II. Gamma rays with pulse width of sub-picosecond range can be generated by injecting femtosecond laser pulses into the electron beam from the vertical 90-degree direction* because the electron beam circulating in the storage ring is focused more tightly in the vertical direction than in the longitudinal direction. The energy, intensity, and pulse width of the gamma rays can be tuned by changing the collision angle between the electron beam and the laser. We are developing pulse width measurement techniques of ultra-short gamma ray pulses at present. As the first step of the pulse width measurement, we used a fast response photodetector, Geiger-mode APD, the time resolution of which is few hundreds picoseconds. Although we cannot measure the pulse width of the gamma rays with sub-picosecond range using this detector, we could measure the pulse width of the gamma rays as 430 ps or less by measuring the timing of Cherenkov radiations generated from the gamma rays. * Y. Taira et al., Nucl. Instrum. Meth. A, in press, 2010.

TUPO014	High-flux Gamma-ray Generation by Laser Compton Scattering in the SAGA-LS Storage Ring	laser, photon, survey, electron	1476
	T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi SAGA, Tosu, Japan
	We constructed an experimental setup for high-flux gamma-ray generation by laser Compton scattering (LCS) in the SAGA-LS storage ring. The SAGA-LS is a synchrotron radiation (SR) facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring. We employed a CO2 laser having a wavelength of 10.6 micrometer to produce gamma-rays in the few MeV region in conjunction with the SR user time. The LCS gamma-ray up to the maximum energy of 3.5 MeV is generated via head-on collision between the laser photons and the 1.4 GeV stored beam. Since the energy acceptance of the storage ring is well above the maximum gamma-ray energy, the LCS experiment can be performed without reducing the beam lifetime. As a first step for high-flux gamma-ray generation, we use a small 10 W CO2 laser for beam test. The LCS event rate is designed to be 2·10⁸ ph/s with a beam current of 300 mA and a laser power of 10 W. A further increase of the LCS event rate in the order of 10¹0 ph/s is expected when a kW class laser is utilized. We report on the characteristics of the LCS gamma-rays observed in the low current beam test and an experimental result for evaluating the gamma-ray flux at a current of 300 mA.

TUPO017	Peculiarities of the Excitation of an Optical Resonator by an Electron Beam	electron, undulator, radiation, damping	1479
	E.G. Bessonov, M.V. Gorbunkov, A.L. Osipov LPI, Moscow, Russia A.A. Mikhailichenko CLASSE, Ithaca, New York, USA
	The peculiarities of the optical resonator excitation by electrons in a FEL based on the Self-Stimulated Undulator Radiation at main and collateral synchronicity conditions are discussed. E.G.Bessonov et al., Self-Stimulated Undulator Radiation and its Possible Applications, http://arxiv.org/ftp/arxiv/papers/10⁰⁹/1009.3724.pdf

TUPO018	Self-stimulated Undulator Klystron	undulator, FEL, electron, kicker	1482
	E.G. Bessonov, A.L. Osipov LPI, Moscow, Russia A.A. Mikhailichenko CLASSE, Ithaca, New York, USA
	The Self Stimulated Undulator Klystron (SSUK) and its possible applications in the Particle Accelerator Physics, incoherent Self-Stimulated Undulator Radiation Sources (SSUR) and Free-Electron Lasers are discussed. E.G.Bessonov et al., Self-Stimulated Undulator Radiation and its Possible Applications: http://arxiv.org/ftp/arxiv/papers/10⁰⁹/1009.3724.pdf

TUPS001	Upgrade of the ESRF Vacuum System	vacuum, controls, cathode, synchrotron	1515
	M. Hahn, J.C. Biasci, H.P. Marques, A. Meunier ESRF, Grenoble, France
	The upgrade program of the ESRF concerns in terms of electron storage ring vacuum chambers mainly the insertion device (ID) sectors. Here the length available for the production of intense synchrotron light is being increased from five to six or even seven meters. The presence of canted ID sectors where two independent synchrotron light beams will be produced in the same straight section requires new quadrupole chambers compatible with the new geometry. A number of long insertion device vacuum chambers for the new ID sectors has already been produced by ESRF and coated with non-evaporable getter (NEG) material, a new generation of in vacuum undulators for the extended ID sections are under preparation. This paper outlines the status of the modification of the vacuum system and informs about consequences for the ESRF NEG coating activity and some recent improvements of the vacuum measurement and control system.

TUPS015	ALBA Storage Ring Vacuum System Commissioning	vacuum, photon, cavity, synchrotron	1551
	E. Al-dmour, D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The ALBA booster and storage ring vacuum system installation has been done in 2009, followed by the installation of the RF cavities and the booster to storage transfer line in 2010. Early 2011, the first phase of insertion devices (ID) installation took place, with three narrow gap NEG coated vacuum chambers have been installed, for the use of two Apple-II undulators and one conventional wiggler. On 8th of March 2011, the storage ring commissioning started and it was marked with the achievement of the first turn in the storage ring on the 9th of March and on the 1st of April 2011, 100 mA of beam current has been accumulated. During this period the vacuum system conditioning took place with very good performance. The base pressure without beam was 4·10^-10 mbar and the average pressure with 100 mA was 7.7·10^-9 mbar. The results of the conditioning together with the latest developments are introduced.

TUPS016	Vacuum System Design for the MAX IV 3 GeV Ring	vacuum, synchrotron, lattice, radiation	1554
	E. Al-dmour, D. Einfeld, J. Pasquaud, M. Quispe CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain J. Ahlbäck, M.J. Grabski, P.F. Tavares MAX-lab, Lund, Sweden
	We describe the conceptual design of the vacuum system of the 3 GeV electron storage ring in the MAX IV facility currently under construction in Lund, Sweden. The standard vacuum chambers are for the most part a cylindrical copper tube with 11 mm inner radius whereas stainless steel will be used at selected locations for beam position monitors, bellows and corrector vacuum chambers. In order to cope with the low vacuum conductance, distributed pumping will be provided through NEG coating of all chambers, including those in dipole magnets making MAX IV the first storage ring to be fully NEG coated. We present the mechanical and thermal design of these chambers and discuss the challenges involved in extracting insertion device radiation as well as coping with the heat load from both IDs and bending magnets in a machine with large bending radius, narrow chambers and tight mechanical tolerance requirements.

TUPS062	The Ground Testing of TPS Ground System	site, impedance, synchrotron, background	1677
	T.-S. Ueng, J.-C. Chang, C.K. Kuan, Y.-C. Lin NSRRC, Hsinchu, Taiwan
	A ground grid of 4 rings and 62 vertical electrodes has been constructed for the TPS storage ring. The ground resistance was designed to be smaller than 0.2 ohms in order to give a good protection of the TPS electrical facility and personnel. In order to match the building construction schedule the TPS ground grid has been installed about 1/6 segment of the construction project each period. The ground impedance of each segment was measured right after the installation. The ground grid with the diameter of 200 m of outside ring and its low impedance value, also the limit testing space, challenged the measurement of ground resistance. Several different methods of ground testing have been used and the measured results are compared each other. These methods include fall-of-potential method, slope method, intersecting curves method and the test-current-reversal method. The final TPS ground impedance will be measured and compared with the calculation from combining the previous several segment measurements. The actual TPS ground resistance should have a smaller value than expected.

TUPS064	Construction Status of the Utility System for the 3GeV TPS Storage Ring	status, controls, booster, power-supply	1683
	J.-C. Chang, J.-R. Chen, Y.-C. Chung, C.K. Kuan, K.C. Kuo, J.-M. Lee, Y.-C. Lin, C.Y. Liu, I. Liu, Z.-D. Tsai NSRRC, Hsinchu, Taiwan
	The construction of the utility system for the 3.0 GeV Taiwan Photon Source (TPS) has been contracted out in the end of 2009. The whole construction of the utility system is scheduled to be completed in the end of 2012. Total budget of this construction is about four million dollars. The utility system includes the electrical power, cooling water, air conditioning, compressed air and fire control systems. The TPS construction site is located adjacent to TLS. Some areas of TPS and TLS are overlapped. Under tight schedule, limit budget and geographic constrains, it is a challenge to complete the utility system construction of TPS on time, on budget, and to specification. This paper presents some main issues and status of the utility system construction for the TPS storage ring.

TUPS065	Design of the De-ionized Water Treatment for Taiwan Photon Source	controls, ion, status, photon	1686
	Z.-D. Tsai, W.S. Chan, C.K. Kuan NSRRC, Hsinchu, Taiwan
	This work presents the water treatment design of Taiwan Photon Source (TPS). The system design is influenced by supplied water quality, water quantity and the selected process scheme. The system is composed of a pretreatment, make-up, and points-of-use filtration systems. The pretreatment system consists of an active carbon tower, a normally cartridge filter and a reversed osmosis (RO) unit. Furthermore, the make-up system consists of an ultraviolent (UV) TOC reduction unit and a ion-exchange resin unit. Following the water treatment process, the proposed system can provide high quality de-ionized water whose resistivity is better than 10 MΩ-cm at 25±0.1 degree C and dissolved oxygen is less than 10 ppb.

TUPS073	Top-Up Safety Simulations for the TPS Storage Ring	quadrupole, electron, sextupole, photon	1707
	H.-J. Tsai, C.C. Chiang, P.J. Chou, C.-C. Kuo NSRRC, Hsinchu, Taiwan
	TPS is a 3 GeV third generation light source and operates in the top-up injection scheme. During the top-up injection, the beamline photon shutters are always open. To ensure the radiation safety of beamline experiments, we studied the possible particle leakage to ID and neighboring bending beamlines. The effects of errors on magnets and beam chamber alignments are investigated.

TUPS094	Girder and Support System for PLS-II Project	multipole, dipole, alignment, quadrupole	1759
	H.-G. Lee, H.S. Han, J.Y. Huang, Y.-G. Jung, D.E. Kim, S.N. Kim, S.H. Nam, K.-H. Park, H.S. Suh PAL, Pohang, Kyungbuk, Republic of Korea
	Pohang Accelerator Laboratory (PAL) is planning to upgrade the Pohang Light Source (PLS) which is a 3rd generation light source operating since 1995. We have designed a new steel magnet girder using new schemes to achieve long-term mechanical stability, vibration suppression and precision adjusting system. Each half cell of girder is composed of three pieces, two multipole magnet girder(MMG) and one dipole magnet girder(DMG). The storage ring girders consist of 48 multipole magnet girders and 24 dipole magnet girders. The new girder systems have been fabricated and tested. Recently the girders have been installing and testing the moving mechanism in the storage ring. In this report, the design consideration for the PLSII girder and support systems are reported.

TUPZ006	Aperture Determination in the LHC Based on an Emittance Blowup Technique with Collimator Position Scan	beam-losses, emittance, injection, optics	1810
	R.W. Assmann, R. Bruce, M. Giovannozzi, G.J. Müller, S. Redaelli, F. Schmidt, R. Tomás, J. Wenninger, D. Wollmann CERN, Geneva, Switzerland M. Alabau IFIC, Valencia, Spain
	A new method to determine the LHC aperture was proposed. The new component is a collimator scan technique that refers the globally measured aperture limit to the shadow of the primary collimator, expressed in σs of rms beam size. As a by-product the BLM response to beam loss is quantified. The method is described and LHC measurement results are presented.

WEPC001	Beam Based Sextupole Alignment Studies for Coupling Control at the ASLS	sextupole, quadrupole, coupling, alignment	1995
	R.T. Dowd, Y.E. Tan ASCo, Clayton, Victoria, Australia
	Offsets in sextupole magnets can be a significant source of coupling in a storage ring and hinder efforts to minimize vertical emittance. Beam offsets in the sextupoles at the Australian Synchrotron Light Source were measured using a response matrix analysis in LOCO with differing magnets strengths. These results were used to obtain an estimate of offset in each sextupole as well as estimate quadrupole contributions to coupling.

WEPC024	LOCO in the ALBA Storage Ring	quadrupole, dipole, optics, coupling	2055
	G. Benedetti, D. Einfeld, Z. Martí, M. Muñoz CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	ALBA is a 3 GeV 3rd generation light source which achieved first stored beam in February 2011, and will be commissioned during 2011. The ring comprises of 112 independent quadrupoles grouped in 14 families and 32 combined gradient dipoles powered in series. This paper reviews the process of recovering the design lattice and the symmetry of the machine, and the effects on orbit and lifetime. The main tool employ for this has been the LOCO implementation provided in the Matlab MiddleLayer. First results shows that the main effect on the symmetry is the difference between bending magnets. As this effect can not be compensated locally at present at the bendings, a global optics correction using all the quadrupoles is used.

WEPC033	Decoupling Problem of Weakly Linear Coupled Double Mini-beta-y Lattice of TPS Storage Ring	coupling, lattice, betatron, resonance	2076
	H.-P. Chang, C.C. Chiang, M.-S. Chiu NSRRC, Hsinchu, Taiwan
	Three double mini-beta-y (DMBy) lattice design of the TPS storage ring is in progress to enhance the photon sources at three of the six long straight sections. For the estimation of Touschek beam lifetime, the TRACY code is used to calculate the momentum acceptance of the linear coupled TPS 3-DMBy lattice. The weak linear coupling was generated by adding some random skew quadrupoles at all quadrupole locations in order to create 1% coupling. Using the Teng’s symplectic rotation form in program may cause trouble in decoupling the one-turn coupled matrix. This report describes how we solve this decoupling problem and some useful references and comments are also presented.

WEPC034	High-level Application Programs for the TPS Commissioning and Operation at NSRRC	quadrupole, controls, target, EPICS	2079
	F.H. Tseng, H.-P. Chang, C.C. Chiang NSRRC, Hsinchu, Taiwan
	For the Taiwan Photon Source (TPS) commissioning and operation we have developed more MATLAB-based application programs and tested them on the Taiwan Light Source (TLS). These additional applications built with the MATLAB Middle Layer (MML) include beta function measurement, dispersion function measurement, chromaticity measurement, chromaticity correction, and tune control. In this paper, we will illustrate what algorithms we use in these applications and show the test results. Especially, in order to get the first beam in the TPS commissioning, we adopt the RESOLVE algorithm for the beam steering and it has been built successfully in UNIX-like systems such as Mac OSX and different Linux versions. It can provide us some exercises of error finding and correction before the TPS commissioning in 2013.

WEPC049	Operation and Storage Ring Calibration with the Transverse Bunch-by-Bunch Feedback System at the Australian Synchrotron	feedback, sextupole, damping, synchrotron	2121
	M.J. Boland, Y.E. Tan ASCo, Clayton, Victoria, Australia D.J. Peake, R.P. Rassool, K.P. Wootton The University of Melbourne, Melbourne, Australia
	The first operational experience with the transverse bunch-by-bunch feedback system for the storage ring shows a doubling of the lifetime and the ability to damp instabilities caused by IVU gap changes. The system was also used to calibrate the ring by doing simultaneous measurements on several single bunches with different bunch currents. Using the bunch-by-bunch system's capability to excite the beam to large amplitudes, the non-linear beam dynamics were also measured and compared with the model.

WEPC064	Long Term Beam Dynamics in Ultra-Low Energy Storage Rings	ion, antiproton, target, scattering	2166
	A.V. Smirnov MPI-K, Heidelberg, Germany A.I. Papash, A.V. Smirnov JINR, Dubna, Moscow Region, Russia M.R.F. Siggel-King, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: "Work supported by STFC, the Helmholtz Association and GSI under contract VH-NG-328." Electrostatic storage rings operate at very low energies in the tens of keV range and have proven to be invaluable tools for atomic and molecular physics experiments. However, earlier measurements showed strong limitations in beam intensity, a fast reduction in the stored ion current, as well as significantly reduced beam life time at higher beam intensities and as a function of the ion optical elements used in the respective storage ring. In this contribution, the results from studies with the computer code BETACOOL into the long term beam dynamics in such storage rings, based on the examples of ELISA, the AD Recycler and the USR are presented.

WEPC066	High Order Non-linear Motion in Electrostatic Rings	lattice, focusing, proton, simulation	2172
	D. Zyuzin, R. Maier, Y. Senichev FZJ, Jülich, Germany
	The advantages of an electrostatic storage ring as compared to a magnetic ring are obvious from the point of view to search for the proton electric dipole moment (pEDM). However the magnetic and electrostatic fields have the different nature and, consequently, different features. In particular, particles moving in electrostatic field, can change their own kinetic energy as electrical field coincides with the direction of motion, which is not so for the magnetic field, where the force is always perpendicular to the direction of motion. The electrostatic rings found many applications in the atomic physics and partly the beam dynamics has been already investigated. However in EDM ring some additional specific features are added, which are considered in this paper.

WEPC069	Impact of Nonlinear Resonances on Beam Dynamics at the SPring-8 Storage Ring	injection, resonance, coupling, betatron	2181
	M. Takao, J. Schimizu, Y. Shimosaki, K. Soutome JASRI/SPring-8, Hyogo-ken, Japan
	For a low emittance storage ring like high brilliant light sources, the improvement of nonlinear beam dynamics is necessary for the stable operation, or for providing large dynamic aperture and momentum acceptance for efficient injection and long Touschek lifetime. At the SPring-8 storage ring it is observed that injection efficiency is affected by the gap heights of the magnet arrays of the in-vacuum insertion devices. The fact that the injected beam of fundamentally oscillating in horizontal direction is limited by the vertical aperture means that coupling resonances influence the beam dynamics. To clarify the phenomena, we studied the nonlinear beam dynamics of transverse betatron motion by means of turn-by-turn method. Then, we found some nonlinear coupling resonances, such as the one by skew sextupole field, are excited to enhance vertical oscillation and to deteriorate the injection efficiency. By analyzing these results, we developed measures to suppress the effect of the nonlinear coupling resonances and to improve the injection efficiency.

WEPC109	Emittance Optimization Using Particle Swarm Algorithm*	emittance, lattice, quadrupole, synchrotron	2271
	Z. Bai, W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	In this paper we use a swarm intelligence algorithm, particle swarm optimization (PSO), to optimize the emittance directly. Some constraint conditions such as beta functions, fractional tunes and dispersion function, are considered in the emittance optimization. We optimize the strengths and positions of quadrupoles to search low emittances. Here an FBA lattice studied in the design of the Hefei Advanced Light Source storage ring is used as the testing lattice. The PSO is shown to be beneficial in the optimization.

WEPC116	A Matrix Presentation for a Beam Propagator including Particles Spin	collider, controls, heavy-ion, scattering	2283
	M. Kosovtsov, S.N. Andrianov, A.N. Ivanov St. Petersburg State University, St. Petersburg, Russia
	Particles beam dynamics in magnetic and electrical fields with spin is discussed. This approach provides a constructive method of matrix presentation derivation for a beam propagator in magnetic and electrical fields. The beam propagator is evaluated in according to the well-known Lie algebraic tools. But in contrast to traditional approaches matrix presentation for Lie propagators bases on two-indexes matrices. This approach permit to apply all of matrix algebra opportunities and advantages in contrast with the tenzor presentation based on multi-indexes description. The necessary computation can be realized in symbolic (using computer algebra codes as Mathematica, Maple, Maxima and so on). The corresponding symbolic objects itself can be stored in special databases and used then in numerical computing. Parallel and distributed conception is well acceptable with the suggested matrix formalism. Some symbolic and numerical results are discussed for problems of long term evolution of particles with spin.

WEPC123	Numerical Algorithm based on the PDE Method for the Solution of the Fokker-Planck Equation	simulation, pick-up, kicker, impedance	2298
	M. Dolinska NASU/INR, Kiev, Ukraine C. Dimopoulou, A. Dolinskii, F. Nolden, M. Steck GSI, Darmstadt, Germany
	Funding: Work supported by HIC for FAIR This paper discus a fast and accurate algorithm for numerical solution of Fokker-Planck equation based on the solution of the parabolic Partial Differential Equations (PDE), where the Crank–Nicholson scheme is used. The stability, convergence and round-off errors of the algorithm are studied. The numerical results on Fokker–Planck equation solution with PDE method are compared with other numerical methods. Using the PDE solver, we will be able to predict the stochastic cooling process of notch filter in storage rings.

WEPC156	Virtual Power Supply Control Environment for the TPS Project	power-supply, controls, EPICS, quadrupole	2349
	Y.-S. Cheng, Y.-T. Chang, J. Chen, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao, C.Y. Wu NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS) is the latest generation of 3 GeV synchrotron light source which has been under construction since 2010. The control system infrastructure of TPS project is based upon the EPICS framework. In order to develop the control applications before power supplies of magnets delivered, it is necessary to set up the virtual control environment to develop high level application programs for the power supplies of magnets in advance. The high level application programs include operation process, degauss process and etc. for power supplies of magnet. The soft-IOCs (Input Output Controller) and various database records are needed to be built to simulate the power supply control environment. In addition, the operation interfaces of power supply will be designed and integrated according to location properties. The efforts will be described at this report.

WEPC159	A Python Tracking Code and GUI for Control Room Operations	controls, lattice, status, dipole	2358
	M.T. Heron, J. Rowland Diamond, Oxfordshire, United Kingdom
	Considerable use has been made in recent years of accelerator physics modelling and online tools under Matlab. These have demonstrated the benefits of operating in a rich integrated environment and further given good portability across projects and operating systems. As a possible alternative to Matlab, Diamond has been evaluating options based on Python. Python together with the Numpy libraries and Qt Graphics provides an environment which offers a lot of the functionality of Matlab. This paper presents these developments, which include a tracking code, symplectic integrator, twiss and response matrix together with a GUI interface.

WEPO013	Septum and Kicker Magnets for the ALBA Booster and Storage Ring	kicker, injection, booster, vacuum	2421
	M. Pont, R. Nunez CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain E. Huttel KIT, Karlsruhe, Germany
	At the ALBA Synchrotron light source 6 kicker and 3 septa magnets are installed for beam injection and extraction. A 100 MeV beam coming from the linac is injected on axis into the Booster. The full energy (3 GeV) beam is extracted from the booster and injected into the Storage Ring, where 4 kicker magnets bring the stored beam close to the septa. All septa are direct driven out-of-vacuum magnets with C shape iron laminated yoke. The magnets are excited by a full sine approx. 300 μs pulse length; the nominal field is 0.15/0.84/0.9 T (booster injection/extraction/storage-ring-injection). The stray field seen by the stored beam is less than 1 μT. The booster kicker magnets are in-vacuum magnets with C-ferrite yoke. The magnets are excited by a 0.4 μs flat top pulse; the nominal field is 0.03/0.04 T (booster injection/extraction). The storage ring kickers have a C-ferrite yoke and a 0.4 μm Ti coated ceramic vacuum chamber. The excitation is done by 6 μs half sine; the nominal field is 0.13 T. The paper will present the design of the elements and their magnetic characteristics. First results of their behaviour during commissioning will also be discussed.

WEPO015	MAX IV 3 GeV Storage Ring Prototype Magnet	dipole, simulation, magnet-design, lattice	2427
	M.A.G. Johansson, L.-J. Lindgren MAX-lab, Lund, Sweden B. Anderberg AMACC, Uppsala, Sweden
	The MAX IV facility, currently under construction, will consist of a 3 GeV storage ring, a 1.5 GeV storage ring, and a full energy injector/SPF/FEL driver. The magnet design for the 3 GeV storage ring is conceptually identical to the MAX III storage ring magnets, with all magnet elements within each cell machined into one solid iron block. A prototype of a matching cell magnet block has been manufactured and mechanical and magnetic field measurements have been performed.

WEPO016	Design of the MAX IV/Solaris 1.5 GeV Storage Ring Magnets	lattice, ion, simulation, dipole	2430
	M.A.G. Johansson MAX-lab, Lund, Sweden
	The MAX IV facility, currently under construction in Lund, Sweden, will consist of a 3 GeV storage ring, a 1.5 GeV storage ring, and a full energy injector/SPF/FEL driver. The Solaris facility, which will be built in Krakow, Poland, will use an identical 1.5 GeV storage ring, injected at 500 MeV. The magnet design for the 1.5 GeV storage ring is conceptually identical to the MAX III and the MAX IV 3 GeV storage ring magnets, with several magnet elements machined into one solid iron block. Detailed design has been done in Opera3D, with a model of the full magnet block being set up and simulated, and iterated against the lattice design.

WEPO020	Magnetic Field Inspection and Analysis of Multipole Lattice Magnets using a Rotating-coil Measurement System*	multipole, quadrupole, sextupole, synchrotron	2442
	J.C. Jan, C.-H. Chang, Y.L. Chu, T.Y. Chung, C.-S. Hwang, C.Y. Kuo, F.-Y. Lin NSRRC, Hsinchu, Taiwan
	A precise rotating-coil measurement system (RCS) was constructed to characterize the field quality and field center of multipole lattice magnets of Taiwan Photon Source (TPS). The mechanical center of magnets is determined by the two references of the magnet-feet and the RCS system is used to characterize the field center. The location of the magnetic field center is quantitatively accurate to better than 20 micro-meter in the horizontal direction; the granite support height of the RCS system is accurate within 5 micro-meter after artificial polishing. The measurement reproducibility of the field center was better than 10 micro-meter when the magnets were reinstalled. The relative accuracy of the multipoles components is better than 2×10^-5. This paper reports the details of the bench construction and the unit composition. The field center with RCS measurement will be compared and discussed with the 3D-coordinate-measuring machine. The multipole errors obtained from RCS will be compared with a Hall-probe measurement system.

WEPS005	Investigation of Intrabeam Scattering in the Heavy Ion Storage Ring TSR	ion, bunching, electron, scattering	2490
	S.T. Artikova, M. Grieser, J. Ullrich MPI-K, Heidelberg, Germany
	Intrabeam scattering (IBS) is a multiple scattering effect between stored beam particles. It leads to diffusion in all three spatial dimensions and thus, causes an expansion of the whole beam. IBS plays an important role in the equilibrium diameter of a low-velocity, electron-cooled ion beam. IBS effects for coasting and bunched 12C⁶⁺ ion beams at an energy of 73.3 MeV were studied using the TSR heavy ion cooler storage ring. Experimental results of the IBS rates are presented.

WEPS030	Ion Optics Alignment in the Electrostatic Double Storage Ring DESIREE	alignment, quadrupole, ion, optics	2547
	P. Löfgren, M. Blom, F. Hellberg, L. Liljeby, A. Simonsson MSL, Stockholm, Sweden P. Reinhed Stockholm University, Stockholm, Sweden
	DESIREE is a cryogenic electrostatic double storage ring under construction at Stockholm University. The two rings have similar circumference, 8.8 m and a common straight section for merged beam experiments. In each ring the ions are guided by two 160° cylindrical deflectors and four 10° deflectors and focused by four quadrupole doublets. In terms of ion optics alignment the quadrupoles are the most important factor for the ion beam acceptance and the goal is to align all quadrupoles with precision of 0.1 mm. DESIREE is constructed as a double walled cryostat with an inner and an outer vacuum chamber. All optical elements are mounted directly on the bottom of the inner chamber. For positioning of the ion optics, the bottom plate is prepared with a number of footprints where each footprint consists of four small machined surfaces that define the height and two alignment holes that define the lateral position. The optical elements were aligned on the bottom plate using a portable measuring device in combination with a level instrument. In this work we describe the alignment procedure in detail and report on the overall precision obtained and the consequence for the ion beam.

THPC001	Progress Towards Implementation of Top-up at the Australian Synchrotron	injection, radiation, photon, interlocks	2904
	G. LeBlanc, P. Bennetto, M.J. Boland, S. Costantin, R.T. Dowd, Y.E. Tan, D. Zhu, E.D. van Garderen ASCo, Clayton, Victoria, Australia
	The Australian Synchrotron Light Source has enjoyed several years of stable operations with a high degree of availability. It is now time to move towards top-up operations to improve the stability and integrated flux of the photon beam. This paper describes the steps that have been taken and what remains to be done in order to implement top-up injection as the normal operation mode for the first user runs of 2012.

THPC002	Implementation of a Low-Emittance Optics for the LNLS UVX Storage Ring	optics, emittance, quadrupole, lattice	2907
	F. H. de Sá, L. Liu, X.R. Resende LNLS, Campinas, Brazil
	In this report we describe the theoretical optimization and implementation of a low-emittance optics for the LNLS UVX storage ring. The emittance is reduced by letting the dispersion be distributed everywhere while keeping the low vertical beta feature. The optimization strategy is based on a series of quadrupole strength scans and selection of points satisfying a number of criteria. The new mode reduces the emittance from 100 nm.rad to 40 nm.rad, including the effects of the already installed insertion devices, and keeps the working point in the same quadrant as the present operation BBY6T mode. Tests have shown a reduction of approximately 20% in the horizontal and vertical beam sizes in the middle of the dipoles, in agreement with the theoretical emittance reduction.

THPC005	First Measurements with a Kicked Off Axis Bunch for Pseudo Single Bunch Mode Studies at SOLEIL	kicker, single-bunch, closed-orbit, synchrotron	2912
	L.S. Nadolski, J.-P. Lavieville, P. Lebasque, A. Nadji, J.P. Ricaud, M.G. Silly, F. Sirotti SOLEIL, Gif-sur-Yvette, France
	At SOLEIL, the time resolved French community benefits of single bunch operation few weeks a year. Meanwhile most of the multi-bunch filling pattern based experiments are not possible due to the low photon flux. Following the pioneer work performed at ALS, a new operation mode is under study at SOLEIL where the storage ring is filled up with a special hybrid mode: ¾ multibunch filling pattern and a single bunch with higher current in the last ¼. The so-called pseudo single bunch-filling pattern is obtained if the closed orbit of the single bunch is not the same as the one of the other bunches. Preliminary results are presented where the pinger magnet time impulse response has been significantly reduced while its frequency was increased from 3 Hz up to 1 kHz. This magnet is used as an additional corrector magnet to change only the single bunch closed orbit. First experimental results observed at one interested beamline are also discussed. S. Kwiatkowski et al., “'CAMSHAFT' Bunch Kicker Design for the ALS Storage Ring", Proc. of EPAC2006, THPLS114, p. 3547, (2006).

THPC006	Experiments to Measure Electron Beam Energy using Spin Depolarization Method on SOLEIL Storage Ring	polarization, electron, beam-losses, synchrotron	2915
	J.F. Zhang, L. Cassinari, M. Labat, A. Nadji, L.S. Nadolski, D. Pédeau SOLEIL, Gif-sur-Yvette, France
	The electron beam energy on SOLEIL storage ring was successfully measured using spin depolarization method after several attempts over the past few years. The experimental results demonstrate that the effective polarization was 91.3%±3% and polarization time was 17±2.3 minutes as expected from the simulation using SLIM code. The beam was depolarized using an AC shaker and the depolarization was monitored using DCCT and beam loss monitors. The beam energy was measured with accuracy up to a few 10^-5.

THPC007	Laser Electron Interaction Simulation for the Femtosecond Bunch Slicing on SOLEIL Storage Ring	laser, electron, wiggler, simulation	2918
	J.F. Zhang, M.-E. Couprie, M. Labat, A. Loulergue, A. Nadji SOLEIL, Gif-sur-Yvette, France
	The interaction of an electron bunch and a laser in a wiggler (modulator) to generate a femtosecond slice is simulated for the slicing project on SOLEIL storage ring, using a code based on Monte-Carlo method and GENESIS. The results from these two codes are consistent with the theoretical values. The maximum modulated energy of the electron bunch and the number of electrons above a certain limit are studied for different wiggler and laser parameters. The transport of the 6D distribution of the sliced bunch from the modulator to the radiators are simulated using AT (Accelerator Toolbox) and ELEGANT, with synchrotron radiation on and taking into account the collective effects of the sliced bunch core.

THPC009	Performance and Upgrade of the ESRF Light Source	emittance, undulator, cavity, vacuum	2924
	J.-L. Revol, J.C. Biasci, J-F. B. Bouteille, J. Chavanne, F. Ewald, L. Farvacque, A. Franchi, G. Gautier, L. Goirand, M. Hahn, L. Hardy, J. Jacob, J.M. Koch, M.L. Langlois, G. Lebec, J.M. Mercier, T.P. Perron, E. Plouviez, K.B. Scheidt, V. Serrière ESRF, Grenoble, France
	The European Synchrotron Radiation Facility (ESRF) is now fully engaged in a large Upgrade Programme of its infrastructure, beamlines and X ray source. In this context, a first set of 10 insertion device straight sections are being lengthened from five to six metres; a number of them will be operated with canted undulators. The insertion devices are themselves subject to an ambitious development programme to fulfil the scientific requirements. The Radio Frequency system upgrade has started with the replacement of the booster klystron-based transmitter by high power solid state amplifiers, and the development of HOM damped cavities operating at room temperature. A completely new DC-AC orbit stabilization system using 224 BPMs and 96 orbit steerers is currently being commissioned. The upgrade is conducted while keeping, and even improving, routine performance for the user service. In particular the recent installation of new skew quadrupole power supplies allows routine operation with ultra low vertical emittance. This paper reports on the present operation performance of the source, highlighting recent developments and those still to come.

THPC013	THz Studies at a Dedicated Beamline at the MLS	radiation, electron, synchrotron, synchrotron-radiation	2933
	R. Müller, A. Hoehl, A. Serdyukov, G. Ulm PTB, Berlin, Germany J. Feikes, M. Ries, G. Wüstefeld HZB, Berlin, Germany
	The Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute is operating the low-energy electron storage ring Metrology Light Source (MLS) in Berlin-Adlershof in close cooperation with the Helmholtz-Zentrum Berlin. The MLS is designed and prepared for a special machine optics mode (low-alpha operation mode) based on a sextupole and octupole correction scheme, for the production of coherent synchrotron radiation in the THz region. At the MLS two bending magnet beamlines dedicated to the use of IR and THz synchrotron radiation are in operation: the MLS-IR beamline optimized for the NIR to FIR, and a dedicated THz beamline optimized for the FIR/THz spectral range. Low-alpha operation optic modes for different ring energies, 250 MeV, 350 MeV, 450 MeV and 630 MeV are available. We compare the THz spectra taken in the different low-alpha modes and discuss the results. J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011). ** R. Müller et al., J. Infrared Milli Terahz Waves, in press (2011), DOI: 10.10⁰⁷/s10762-011-9785-6.

THPC021	Status of Bunch Deformation and Lengthening Studies at the ANKA Storage Ring	radiation, diagnostics, cavity, photon	2951
	N. Hiller, A. Hofmann, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller KIT, Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. At the ANKA storage ring (Karlsruhe, Germany) we use a Hamamatsu synchroscan streak camera to study the current dependent bunch lengthening and deformation effects . Previously the camera was used at an IR port, being available only occasionally. In October 2010, a dedicated “beam line” for the streak camera became operational. It is designed to have minimum dispersion and sufficient flux in the optical range at which the camera is most sensitive. This allows us to measure bunch profiles for a single bunch with a charge of less than 15 pC (40 μA), previously more than 55 pC were required to obtain a comparable signal. Along with the design and built-up, we present further measurements of bunch length and shape for different momentum compaction factors, RF voltages, beam energies and bunch charges to provide a complete bunch length map of the low alpha mode at ANKA.

THPC024	Lattice Candidates for the ILSF Storage Ring	lattice, emittance, dipole, synchrotron	2957
	H. Ghasem IPM, Tehran, Iran D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain F. Saeidi ILSF, Tehran, Iran
	Iranian Light Source Facility (ILSF) is a new third generation synchrotron light source which is currently in design and will build in Iran. It will provide a high photon flux density to cover requirements of experimental science in several fields. Regarding to the proposed budget and in order to produce high quality X-ray pulses with several photon beamlines as a request of users, it is decided to design a very low emittance (ε<5nm-rad) storage ring with a typical beam intensity of 400 mA and circumference in the range of 280 m to 320 m. A number of design options with different lattice structure types, circumferences, etc., are explored and we present two designed lattice candidates of the ILSF storage ring. The associated Accelerator Physics issues are discussed.

THPC025	Booster Design for ILSF	booster, synchrotron, dipole, electron	2960
	H. Ghasem IPM, Tehran, Iran E. Ahmadi ILSF, Tehran, Iran D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	A full energy 3 GeV booster synchrotron has been designed to boost electron beam to the target energy of 3 GeV for the proposed third generation synchrotron light source (ILSF) that will be constructed in Iran. The primary goal of the ILSF booster is to design a synchrotron which can deliver a small emittance (ε<30 nm-rad), while at the same time has a low cost in construction. In order to design lattice for the booster, two configurations for booster have been considered. In the first configuration, booster is designed based on locating in a separate tunnel as 3 GeV storage ring inside the ring and in the second configuration, the booster is optimized for placing inner to the ring with one shared wall as service area of ILSF storage ring. Several types of lattice with various circumferences have been explored for the booster synchrotron in each configuration and this paper presents results of linear and nonlinear optimization of the main designed lattice for booster in both configurations.

THPC027	Top-up Operational Experience at Elettra	injection, booster, radiation, controls	2966
	E. Karantzoulis, A. Carniel, S. Krecic ELETTRA, Basovizza, Italy
	Since May 2010 Elettra, the third generation Italian light source, operates regularly for users at both 2 and 2.4 GeV in top-up. In this paper the experience during more than a year of operation in top-up at both user energies is discussed and the machine up time statistics presented and compared with the before top up period.

THPC028	A Proposal of Short X-ray Pulse Generation from Compressed Bunches by mm-wave iFEL in the SPring-8 Upgrade Plan	wiggler, injection, electron, simulation	2969
	M. Masaki, K. Fukami, C. Mitsuda, T. Watanabe JASRI/SPring-8, Hyogo-ken, Japan
	In the SPring-8 upgrade plan, short pulse options are prepared for time-resolved experiments of pico-second order with high repetition rate. The best scenario is that selected bunches have equilibrium bunch length of 1 ps or less. A mm-wave storage-ring iFEL may be one possible solution for it. If resonant wavelength of the FEL is a few millimeters, which is about ten times longer than typical short bunch length of 0.3 mm corresponding to 1 ps, almost all electrons of a bunch can be confined in one valley of ponderomotive potentials formed by the FEL mechanism. The system consists of a helical wiggler with period length of several meters and a mm-wave resonator. Numerical simulations with coherent synchrotron radiation effect at bunch charge of 479 pC show that an ultra-short injection bunch is trapped in a mm-wave “bucket” and kept shorter than 1 ps (r.m.s.) even after twice the longitudinal damping time from the injection. The ultra-short bunches need to be injected from the XFEL linac. XFEL-to-Storage Ring beam transport line is designed to suppress dispersions which cause bunch lengthening. Tracking calculations show promising results for bunch qualities at the transport line.

THPC029	Ultra-low Emittance Light Source Storage Ring Consisting of 5-Bend Achromat Cells with Four Long Straight Sections	lattice, emittance, undulator, wiggler	2972
	K. Tsumaki JASRI/SPring-8, Hyogo-ken, Japan
	The 6 GeV ultimate storage ring (USR) consisting of ten bend achromat cells has been proposed* and applied it to the SPring-8 Storage ring*. It has the same circumference as the SPring-8 storage ring, but does not have four long straight sections, where the SPring-8 storage ring does. The cell length is twice of that of the SPring-8 storage ring and the number of cell is half of the SPring-8. The photon beam line positions would deviate from those of the existing one. To avoid these problems, we designed a storage ring that has four long straight sections and same cell number. The cell is changed from ten bend achromat to five bend achromat and the cell length is shortened to 30 m which is the same length of the SPring-8 storage ring unit cell. The total ring consists of 44 five bend achromat cells and four long straight section cells. The emittance is 10⁴ pm and it will reduce to less than 50 pm by radiation damping of wigglers and undulators. The brightness is expected to be more than 10²2 phs/s/mm²/mrad² in 0.1%BW with 200 mA beam current. K. Tsumaki, N. Kumagai, NIM A 565 (2006) 394. ** K. Tsumaki, N. Kumagai, Proc. of EPAC06, THPLS035, p. 3362 (2006).

THPC030	Design of a BeamTransport Line from the SACLA Linac to the SPring-8 Storage Ring	lattice, emittance, linac, beam-transport	2975
	K. Tsumaki, K. Fukami, T. Watanabe JASRI/SPring-8, Hyogo-ken, Japan S. Itakura, N. Kumagai RIKEN/SPring-8, Hyogo, Japan
	The SPring-8 Angstrom Compact Free Electron Laser (SACLA) linac has high beam qualities. The normalized emittance is less than 1 mm.mrad and the bunch length is less than 100 fs. If this high quality beam is injected to the SPring-8 storage ring, many interesting experiments can be done. On the other hand, the upgrade of the SPring-8 storage ring is under contemplation. The dynamic aperture of the new storage ring is expected to be so small that the small emittance beam is required to keep high beam injection efficiency. The SACLA linac beam also fulfills this requirement. For these reasons, it was decided to connect the SACLA linac and the SPring-8 storage ring. Since there is already an injection transport line from the SPring-8 synchrotron to the storage ring, the new transport line from the linac to this transport line has been constructed. We designed the three types of magnet lattice for the new transport line; FODO, Double Bend Achromat and Triple Bend Achromat lattice. Emittance growth and bunch lengthening are calculated for each lattice and the beam qualities are compared. In this paper, lattice design and the comparison of the beam quality for each lattice are described. C. Mitsuda et al., this conference.

THPC031	Measurement of Longitudinal Dynamics of Injected Beam in a Storage Ring	injection, simulation, synchrotron, booster	2978
	T. Watanabe, T. Fujita, M. Masaki, K. Soutome, S. Takano, M. Takao, K. Tamura JASRI/SPring-8, Hyogo-ken, Japan
	Experimental observation of longitudinal dynamics of injected beam in a storage ring has been demonstrated. Since the injected beam undergoes synchrotron oscillation in a longitudinal phase space, two projected values, i.e., a bunch duration and an energy spread, oscillate at twice the synchrotron frequency. At SPring-8, the initial energy spread (~0.126%) at the injection goes up and down until it reaches the equilibrium energy spread (~0.11%). If the injection timing should not be optimized, an asymmetrically enhanced oscillation could distort the injection efficiency. The observation of such an oscillation helps make sure that no significant injection loss occurs. More importantly, the scheme is expected to enable us to observe non-linear longitudinal dynamics of ultra-short bunches injected from the XFEL linac; the bunches are in near future going to be transferred from the linac to the storage ring via 600-meter long transports, in which strong coherent synchrotron radiation and other high peak-current effects will not be ignorable. Experimental results obtained by a dual-scan streak camera and other devices as well as numerical simulations will be presented.

THPC034	Post-earthquake Recovery of PF Ring and PF-AR	injection, vacuum, survey, alignment	2984
	T. Honda, T. Aoto, S. Asaoka, K. Endo, K. Haga, K. Harada, Y. Honda, M. Izawa, Y. Kobayashi, A. Mishina, T. Miyajima, H. Miyauchi, S. Nagahashi, N. Nakamura, T. Nogami, T. Obina, T. Ozaki, C.O. Pak, H. Sakai, S. Sakanaka, H. Sasaki, Y. Sato, K. Satoh, M. Shimada, T. Shioya, M. Tadano, T. Tahara, T. Takahashi, R. Takai, Y. Tanimoto, K. Tsuchiya, T. Uchiyama, A. Ueda, K. Umemori, M. Yamamoto KEK, Ibaraki, Japan
	When the unprecedented scale of earthquake occurred in Japan on the afternoon of March 11, 2011, PF ring and PF-AR, two synchrotron light sources in KEK, also suffered various damages. At PF ring, a formed bellows in a wall current monitor was broken, and atmospheric air rushed into the beam duct. At PF-AR, which is installed in the underground tunnel, the alignment of the ring magnets seemed to be disordered to an order of ten mm. At both rings, a lot of electronics racks and toolboxes in the control rooms or in the experimental halls were tilted or tipped over. It was extremely fortunate that the user operation had just been stopped on the morning of that day, and all the gate valves in the rings and to the beam lines had already been closed for the scheduled shutdown. A wide area blackout took place at the big earthquake, and the electric power for the accelerator was interrupted over the next two weeks because of temporal shortage of the electricity in the eastern part of Japan. In April, we could start detailed investigation of machine damages and repair works towards recommissioning of the rings before the summer and resumption of the user operations in the autumn.

THPC037	Accelerators of the Central Japan Synchrotron Radiation Facility Project (II)	synchrotron, booster, electron, linac	2987
	N. Yamamoto, M. Hosaka, A. Mano, H. Morimoto, K. Takami, Y. Takashima Nagoya University, Nagoya, Japan Y. Hori KEK, Ibaraki, Japan M. Katoh UVSOR, Okazaki, Japan S. Koda SAGA, Tosu, Japan S. Sasaki JASRI/SPring-8, Hyogo-ken, Japan
	Central Japan Synchrotron Radiation (SR) Facility Project is making progress for the service from FY2012. The construction of SR building is almost completed in the Aichi area of Japan, and the installs of accelerators will start in a few week. The key equipments of our accelerators are an 1.2 GeV compact electron storage ring that is able to supply hard X-rays and a full energy injector for top-up operation. The beam current and natural emittance of the storage ring are 300 mA and 53 nmrad. The circumference is 72 m. The magnetic lattice consists of four triple bend cells and four straight sections. The bending magnets at the centers of the cells are 5 T superconducting magnets and the critical energy of the SR is 4.8 keV. The injector consists of a 50 MeV linac and a booster synchrotron with the circumference of 48 m. To save construction expenses, the injector is built at inside of the storage ring. More than ten hard X-ray beam-line can be constructed. One variable polarization undulator will be installed in the first phase. The top-up operation will be introduced as early as possible.

THPC042	Status and Development of the SAGA Light Source	laser, controls, undulator, linac	2996
	T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi SAGA, Tosu, Japan
	The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring, and has been stably providing synchrotron light since 2006. The annual failure time is less than 1% of the user time in the recent two years. Three insertion devices are installed in the storage ring: an APPLE-II undulator, a planar type undulator (Saga Univ.) and a 4 T superconducting wiggler (SCW). The SCW contains a hybrid three-pole magnet; the main pole of the magnet is surrounded by superconducting coils while side poles are normal conducting magnets. The main pole of the SCW is cooled by a GM cryocooler, which allows the SCW be operated without liquid helium. Since the installation in March 2010, the SCW has been operated stably. To control the ID parameters during the user time, a feed-forward correction system which minimizes the ID effects on the emittance coupling was developed. The laser Compton Gamma-rays were generated by using a CO2 laser and were used for beam energy measurement. In addition, research works on the beam lifetime and interaction between electron beam and crystal, and development of a multipole magnet are in progress.

THPC044	Operation and Performance Upgrade of the Soleil Storage Ring	undulator, vacuum, photon, feedback	3002
	A. Nadji, P. Brunelle, M.-E. Couprie, J.-C. Denard, J.-M. Filhol, J.-F. Lamarre, P. Lebasque, A. Loulergue, P. Marchand, L.S. Nadolski, R. Nagaoka, M.-A. Tordeux SOLEIL, Gif-sur-Yvette, France
	SOLEIL delivers photons to 24 beamlines. Up to 22 very diverse insertion devices (IDs) are now installed on the storage ring, and 4 more will come by summer 2011, including a Cryogenic undulator and an electromagnetic/permanent magnet helical undulator, both designed and built at SOLEIL. Work is continuing on beam dynamics and magnetic corrections to reduce the nonlinear effects of all these IDs. A new optics incorporating an additional quadrupole triplet in one long straight section has been successfully tested and will be put in operation by fall 2011. A new coupling correction will also be implemented to maintain the ratio of the vertical to the horizontal emittances at 1% for any IDs configuration. The electron beam orbit stability has been significantly improved reaching a residual noise of 300 nm RMS. Photon LIBERA modules of X-BPM located on the bends, will be integrated soon in the orbit feedback loops. 4905 hours have been delivered in 2010 to the beamlines with an availability of 96.3%. The user operation with the maximum current of 500 mA is foreseen to start by fall 2011, after the completion of the radiation safety tests of the beamlines.

THPC052	Progress Towards Top-up Operation at SSRF	injection, radiation, controls, photon	3008
	Z.T. Zhao, H.H. Li, L. Yin, W.Z. Zhang SINAP, Shanghai, People's Republic of China
	The Shanghai Synchrotron Radiation Facility (SSRF) has been in operation for user experiments in decay mode since May 2009. In the meantime various activities to prepare top-up operation at SSRF, including safety analysis and simulation, dedicated instrumentations and interlocks, control software, radiation measurements, injection optimization and top-up operation tests, have been carried out. In this paper, the progress towards top-up operation at SSRF is described together with its achieved performance.

THPC054	Project Status of the Polish Synchrotron Radiation Facility Solaris	linac, synchrotron, cavity, radiation	3014
	C.J. Bocchetta, P.P. Goryl, K. Królas, M. Mlynarczyk, M.J. Stankiewicz, P.S. Tracz, Ł. Walczak, A.I. Wawrzyniak Solaris, Krakow, Poland J. Ahlbäck, Å. Andersson, M. Eriksson, M.A.G. Johansson, D. Kumbaro, S.C. Leemann, L. Malmgren, J.H. Modéer, P.F. Tavares, S. Thorin MAX-lab, Lund, Sweden E. Al-dmour, D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	Funding: European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09 The Polish synchrotron radiation facility Solaris is being built at the Jagiellonian University in Krakow. The project is based on an identical copy of the 1.5 GeV storage ring being concurrently built for the MAX IV project in Lund, Sweden. A general description of the facility is given together with a status of activities. Unique features associated with Solaris are outlined, such as infra-structure, the injector and operational characteristics.

THPC057	Operation of the ALBA Injector	linac, booster, emittance, injection	3023
	M. Pont, U. Iriso, R. Muñoz Horta, F. Pérez CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The ALBA injector made of a 100 MeV linac, operating at 110 MeV, and a full energy (3 GeV) booster synchrotron has been routinely in operation since October 2010. The stability of the linac and of the booster on reliability and performance is examined. Also results on the beam performance obtained with the installed diagnostic equipment will be discussed.

THPC058	The MAX IV Synchrotron Light Source	linac, emittance, lattice, vacuum	3026
	M. Eriksson, J. Ahlbäck, Å. Andersson, M.A.G. Johansson, D. Kumbaro, S.C. Leemann, F. Lindau, L.-J. Lindgren, L. Malmgren, J.H. Modéer, R. Nilsson, M. Sjöström, J. Tagger, P.F. Tavares, S. Thorin, E.J. Wallén, S. Werin MAX-lab, Lund, Sweden B. Anderberg AMACC, Uppsala, Sweden L.O. Dallin CLS, Saskatoon, Saskatchewan, Canada
	The MAX IV synchrotron radiation facility is currently being constructed in Lund, Sweden. It consists of a 3 GeV linac injector and 2 storage rings operated at 1.5 and 3 GeV respectively. The linac injector will also be used for the generation of short X-ray pulses. The three machines mentioned above will be descibed with some emphasis on the effort to create a very small emittance in the 3 GeV ring. Some unconventional technical solutions will also be presented.

THPC059	Recent Improvements to the Lattices for the MAX IV Storage Rings	lattice, injection, optics, dipole	3029
	S.C. Leemann MAX-lab, Lund, Sweden
	Construction of the MAX IV facility started early this year. The facility will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production of x-rays while the 1.5 GeV ring will serve UV and IR users. Recently, the lattices for the storage rings in the MAX IV facility were updated. In the 3 GeV storage ring the vertical beam size in the long straights has been reduced. The lattice of the 1.5 GeV storage ring has been updated to take into account first results from detailed magnet and vacuum system designs. Additionally, a new injection method to facilitate commissioning of the storage rings has been studied. This paper summarizes the changes made in the lattices and the effect of these modifications.

THPC061	Comparison of Linear Optics Correction Means at the SLS	optics, quadrupole, betatron, closed-orbit	3032
	M. Aiba, M. Böge, J.T.M. Chrin, N. Milas, T. Schilcher, A. Streun PSI, Villigen, Switzerland
	The experimental determination of linear optics is a fundamental prerequisite to achieving a high performance storage ring. In order to further enhance SLS performance and to simulataneously reveal the limitations of the various techniques, we perform a systematic study of linear optics optimization using various independent methods. These include an analysis of the orbit reponse (LOCO), turn-by-turn data, and the response of the tune, whose correction is accomplished using the standard SLS procedure of varying the quadrupole strengths. A comparison of results from these procedures, which use fully independent observables, provides us with a valuable cross-check. For example, the betatron phase advances between BPMs, which is independent of BPM calibration, confirms the optics correction as determined from LOCO. The linear optics are hence better optimized, and these procedures, LOCO in particular, further serve to expose any previously hidden mis-calibration of parameters e.g. from BPMs and corrector magnets. Systematic errors from turn-by-turn data could also be vastly reduced by a better synchronization of the BPM triggers with the electron beam.

THPC063	A 2.9 Tesla Room Temperature Superbend Magnet for the Swiss Light Source at PSI	power-supply, dipole, vacuum, synchrotron	3038
	A.L. Gabard, D. George, M. Negrazus, L. Rivkin, V. Vrankovic PSI, Villigen, Switzerland Y. Kolokolnikov, P. Vobly BINP SB RAS, Novosibirsk, Russia
	The Swiss Light Source (SLS) at the Paul Scherrer Institute (PSI) in Villigen, Switzerland, is a 3rd generation synchrotron light source. With an energy of 2.4 GeV, it provides high brightness photon beams for research in materials science, biology and chemistry. The SLS storage ring contains 36 room temperature bending magnets, all of which produce light for experimental use; at the design energy of 2.4 GeV, they have a maximum magnetic field of 1.4 Tesla. Light is produced along the entire bending arc but can only be transferred to the external experimental facilities from selected short portions of the beam path. In cooperation with the Budker Institute for Nuclear Physics (BINP) in Novosibirsk, Russia, three of these magnets were replaced with new room temperature magnets with short regions of high magnetic field up to 2.9 Tesla. This enabled the production of intense light beams at shorter wavelengths than from the existing magnets. The critical energy of the 2.9 T magnet is 11.1 keV, compared to the 5.4 keV of the normal bend. This paper describes the design, including the multiple restraints, together with the measurement and commissioning of these so-called superbends.

THPC064	Design Study of Low Emittance Lattice for Taiwan Light Source at 1 GeV	emittance, lattice, dynamic-aperture, wiggler	3041
	C.Y. Lee NTHU, Hsinchu, Taiwan C.C. Chiang, P.J. Chou NSRRC, Hsinchu, Taiwan S.-Y. Lee IUCEEM, Bloomington, Indiana, USA
	We explored the possibility that the existing TLS storage ring to be operated at 1 GeV as a high brightness VUV light source after the completion of 3 GeV Taiwan Photon Source. To increase the spectral brightness, we need to reduce the beam emittance in the storage ring as much as possible. We first pursue the lowest emittance which is possible without altering the existing hardware configuration. The theoretical minimum emittance that could be achieved at 1 GeV for non-achromatic lattice is 3.8 nm-rad. However, this could not be achieved without introducing harmonic sextupoles. Preliminary results of low emittance lattice without harmonic sextupoles in TLS storage ring will be presented.

THPC069	Studies to Optimize the Diamond Light Source Booster Synchrotron as a 100 MeV Storage Ring	booster, quadrupole, synchrotron, linac	3053
	C. Christou, M.T. Heron, J. Rowland Diamond, Oxfordshire, United Kingdom S. Gayadeen University of Oxford, Oxford, United Kingdom
	The injection chain for the Diamond Synchrotron Light Source consists of a 100 MeV Linac and 3 GeV booster synchrotron. These were commissioned in 2005 and 2006 respectively, and have provided acceptable performance as an injector since then. To advance a programme of work in evaluating and optimizing new control algorithms for orbit stability on the Diamond Storage Ring it was decided to use the booster synchrotron as a test platform by operating it in DC mode at 100 MeV. In support of this work and to improve the operational performance of the booster a series of studies have been carried out to better understand and characterize it. This work and the results will be presented.

THPC070	An Automated Statistical Analysis Package for the Study of Synchrotron Light Source Operation	cavity, beam-losses, monitoring, synchrotron	3056
	C. Christou, C.P. Bailey, V.C. Kempson, V.J. Winter Diamond, Oxfordshire, United Kingdom
	Machine faults and interruptions to user beam at Diamond Light Source are recorded in a Fault Log Database (FLDB) running under Microsoft Access. The scope of numerical analysis in Access is limited, and so an advanced data analysis package has been written in Matlab to exploit the powerful numeric functions available in this environment to automatically analyze machine faults and summarize data for reliability reports. Figures of merit such as mean time between failure (MTBF), mean time to repair (MTTR), total up time and total number of faults over the machine as a whole and by technical group can be calculated, and more advanced Pareto and Weibull analyses can be instantly generated. Data is presented for Diamond Light Source both for the latest year of operation and since user beam began in 2007, and the impact of different technical groups, in particular the storage ring RF, is considered. Failure distributions and the underlying hazard functions are produced and compared with statistical models to highlight deviations from randomly occurring events and to quantify changes in failure probability with time.

THPC079	Echo-enabled Harmonic Generation at DELTA	undulator, laser, electron, bunching	3074
	R. Molo, M. Bakr, H. Huck, M. Höner, S. Khan, A. Nowaczyk, A. Schick, P. Ungelenk, M. Zeinalzadeh DELTA, Dortmund, Germany
	Funding: Supported by DFG, BMBF, and the Federal State NRW We present conceptual studies of the realization of the echo-enabled harmonic generation (EEHG) technique proposed by G. Stupakov* as an upgrade of the present coherent harmonic generation (CHG) project at the DELTA storage ring*. EEHG allows to reach shorter wavelengths compared to the CHG scheme. In addition to the optical klystron used for CHG, a third undulator is needed for a second energy modulation of the electron bunch, followed by an additional strong dispersive section. Installing these insertion devices requires a new long straight section in the storage ring and a new lattice configuration. G. Stupakov Phys. Rev. Lett. 10², 074801 (2009) ** A. Schick et al., this conference

THPC123	Injector Layout and Beam Injection into Solaris	injection, linac, gun, klystron	3173
	A.I. Wawrzyniak, C.J. Bocchetta Solaris, Krakow, Poland S.C. Leemann, S. Thorin MAX-lab, Lund, Sweden
	Funding: European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09 The Solaris synchrotron radiation storage ring to be built in Krakow, Poland is based on the MAX IV 1.5 GeV design. The injector will be a linear accelerator and its components identical to those for the MAX IV project, however, injection is not at full energy and the injector layout is different. The linac and transfer line layout, optics and injection scheme into the storage ring is presented and an analysis of accumulation before energy ramping is discussed.

THPC137	Low Emittance Booster Design for CANDLE Storage Ring	booster, emittance, injection, synchrotron	3209
	G.S. Zanyan, B. Grigoryan, K. Manukyan, A. Sargsyan, V.M. Tsakanov CANDLE, Yerevan, Armenia
	The progress in synchrotron based research made the top up operation mode of storage rings as the most attractive option both from the beam lifetime and the user points of view. To provide reliable operation of the facility at top-up injection mode the full energy low emittance new booster ring for 3 GeV CANDLE storage ring is designed. The compact synchrotron magnets with integrated quadrupole and sextupole components are used. The new design provides 20 nm emittance at the top energy with sufficient dynamic aperture and optimal optical properties at straight section for effective extraction. The complete design of the new booster and beam dynamics issues during the energy ramping are presented.

THPC140	Design, Tuning and Results of the Pulsed Magnetic Systems for the Beam Injection in the SOLEIL Storage Ring Operated in ‘Transparent’ Top Up Mode	septum, kicker, injection, vacuum	3215
	P. Lebasque, R. Ben El Fekih, M. Bol, J. Da Silva Castro, A. Hardy, C. Herbeaux, J.-P. Lavieville, A. Loulergue, J.L. Marlats, D. Muller, G. Renaud, J.P. Ricaud SOLEIL, Gif-sur-Yvette, France
	From the beginning, the SOLEIL Storage Ring was designed to operate in Top Up injection mode. So all equipments involved have been specified to generate as small as possible beam perturbations of the stored beam during the electron beam injection. This concerns many aspects of the design and realization of the injection pulsed magnets (kickers and septa), their vacuum chambers, pulsed power supplies and timing electronics. Despite quite satisfactory results of pulsed magnetic measurements in labs, a still too large perturbation was observed on the e^- beam orbit during the Storage Ring commissioning. Therefore a strong work of systematic measurements, analysis of each phenomena, tuning or modification of each device was led until reaching rather good and acceptable performances. This paper will present the results obtained. At this stage, the Storage Ring beam orbit is sufficiently stable in Top Up injection mode so that it is almost transparent to the 24 beam lines, even for the most sensitive ones. After a summary of the main significant topics, we present the developments foreseen to further improve the performances and make a new step towards a “perfect” Top Up injection.

THPC144	The Construction Status of Beam Transport Line from XFEL-linac to SPring-8 Storage Ring	beam-transport, lattice, linac, alignment	3224
	C. Mitsuda, N. Azumi, T. Fujita, K. Fukami, H. Kimura, H. Ohkuma, M. Oishi, Y. Okayasu, M. Shoji, K. Tsumaki, T. Watanabe JASRI/SPring-8, Hyogo-ken, Japan M. Hasegawa, Y. Maeda, T. Nakanishi, Y. Tukamoto, M. Yamashita SES, Hyogo-pref., Japan N. Kumagai, S. Matsui RIKEN/SPring-8, Hyogo, Japan
	The beam transport line from XFEL-linac to SPring-8 storage ring is now under construction to use the ultra short bunched electron beam at the storage ring. The newly constructed line is about 300 m, which is just a half of the whole path from the XFEL linac to the storage ring. The beam extracted from XFEL-linac is guided to the beam transport tunnel connected to the matching section of booster synchrotron bending by 55.2 degrees horizontally and by 10.0 degrees vertically. A double-bend based lattice was adopted to reasonably suppress emittance growth and bunch lengthening. Supposing a bunch length and horizontal emittance at the exit of the XFEL-linac are estimated about 100 fs and 0.04 nmrad respectively, it is expected that the current beam emittance in storage ring is improved to about 0.4 nmrad and almost same bunch length including coherent synchrotron radiation effect. In 2010, the construction of extracting part from XFEL-linac was completed and we finished the installation and alignment of main components. The conceptual design and construction status of transport line will be presented with the emphasis on the detail magnet design and the fabrication.

THPC147	TPS SR Kicker Prototype Installation Status*	kicker, injection, high-voltage, vacuum	3230
	Y.-H. Liu, C.K. Chan, C.-S. Chen, Y.L. Chu, K.H. Hsu, H.P. Hsueh, C.K. Kuan, C.Y. Kuo, C.-S. Yang NSRRC, Hsinchu, Taiwan
	The purpose of this paper is to illustrate the installation sequence of TPS SR kicker. Because of adding the rotation function in row direction, the position of every component of kicker must be very precise. The kicker magnet and EMI enclosure were fastened on the rotation motor plate which could rotate ±3.0 mrad. The ceramic chamber remain fixed on the bottom plate in order to let the bellow stress free during rotation. After installation, the inductance measurement and the high voltage breakdown test were also tested. The experimental results showed the good uniformity and reached the expected request. The field mapping and EMI prevention schemes will be tested in the future.

THPC149	Development of PrFeB Cryogenic Undulator (CPMU) at SOLEIL	undulator, cryogenics, vacuum, permanent-magnet	3233
	C. Benabderrahmane, P. Berteaud, N. Béchu, L. Chapuis, M.-E. Couprie, J.P. Daguerre, J.-M. Filhol, C. Herbeaux, A. Lestrade, M. Louvet, J.L. Marlats, K. Tavakoli, M. Valléau, D. Zerbib SOLEIL, Gif-sur-Yvette, France
	A R&D programme for the construction of a 2 m long 18 mm period CPMU is under progress at SOLEIL. The cryogenic undulator will provide photons in the region of 1.4 to 30 keV. It will be installed in the next few months on the long straight section (SDL13) of the storage ring, and could be used later on to produce photons for the NANOSCOPIUM beamline. The use of PrFeB which features a 1.35 T remanence (Br) at room temperature enables to increase the peak magnetic field at 5.5 mm minimum gap, from 1.04 T at room temperature to 1.15 T at a cryogenic temperature of 77 K. Praseodymium was chosen instead of Neodymium magnetic material, because it is more resistant against the appearance of the Spin Reorientation Transition. Different corrections were performed first at room temperature to adjust the phase error, the electron trajectory and to reduce the multipolar components. The mounting inside the vacuum chamber enables the fitting of a dedicated magnetic measurement bench to check the magnetic performance of the undulator at low temperature. The results of the magnetic measurements at low temperature and the comparison with the measurement at room temperature are reported.

THPC156	Performance of the PETRA III APPLE II Undulator	undulator, multipole, closed-orbit, optics	3254
	J. Bahrdt, W. Frentrup, A. Gaupp, M. Scheer HZB, Berlin, Germany K. Balewski, J. Keil, A. Schöps, M. Tischer DESY, Hamburg, Germany
	A 5m-long APPLE II undulator has been built in collaboration between Helmholtz-Zentrum Berlin and DESY Hamburg. Magnetic field measurements after the final shimming in the laboratory are presented. The device has been installed in the storage ring and machine studies have been performed. The tune shifts in the elliptical and the inclined mode are in agreement with predictions from theory. The dynamic field integrals have successfully been minimized in the storage ring with so-called L-shims (rectangular iron sheets) which are placed at the undulator center at the magnet edges.

THPC171	Performance of ID at ALBA	vacuum, wiggler, undulator, insertion	3299
	J. Campmany, J. Marcos, V. Massana CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The new synchrotron light source ALBA is currently being commissioned along with the first phase of beamlines. Up to 6 beamlines are using light produced by Insertion Devices. There are up to four types of IDs: 2 Apple-II undulators (EU62 and EU71) operating at low energies, one conventional wiggler (MPW80) operating in the range of 2 – 20 keV, two in-vacuum undulators (IVU21) operating in the range 5 – 30 keV and a superconducting wiggler (SCW30) operating in the range of 40 keV. Installation of the IDs has been done in two steps. First, the out-vacuum devices (EU62, EU71 and MPW80) have been mechanically installed. Initial commissioning of Storage Ring has been done with their gaps opened to maximum value. Then, their gap has been closed to study the effect in the beam dynamics. In the second step, the in-vacuum devices (both IVU21 and the SCW30) have been installed and tested. In this paper we present the first results and performances of the insertion devices obtained both in Site Acceptance Test and during the first months of commissioning with beam.

THPO001	Design Power Supply Considerations to Compensate Booster Power Supply Effects on the SOLEIL Storage Ring	booster, power-supply, controls, dipole	3335
	J.-P. Lavieville, R. Ben El Fekih, S. Bobault, D. Muller, L.S. Nadolski SOLEIL, Gif-sur-Yvette, France
	Top-up injection mode has been routinely in operation since March 2009 for various bunch filling patterns at Synchrotron SOLEIL. The electron beam stored current is maintained within 1%. At each injection the 3 Hz booster power supplies are ramped up and down over 10 seconds every 3 minutes in average. During this time DC and AC perturbations are observed on the storage ring horizontal closed orbit. Typically, the beamline source points can be shifted up to 10^-20 μm and the amplitude of the 3Hz frequency is multiplied by a factor 9. The origin of these perturbations lies in the imperfect compensation of the magnet currents circulating along the booster ring located inside the storage ring. To compensate these disturbances, a wire loop was installed in the booster cable tray fed by an in-house developed power supply. Its output current is driven by direct measurement of the main currents of the booster dipole, quadrupole, sextupole power supplies with a proper amplitude and phase shift. This paper presents the determination of the compensation needs according to beam measurements, the original design and the performance reached when this power supply is acting.

THPO007	Operation Status of SSRF Power Supplies and Interlocks for Top-up Operation	power-supply, controls, HOM, quadrupole	3349
	R. Li, C.L. Guo, M.M. Huang, T.J. Shen SINAP, Shanghai, People's Republic of China
	Digital switching mode magnet power supplies are used in SSRF accelerators which have been operating since 2008. Summary of the operation and maintenance of these power supplies will be shared over here. The availability of the power supplies is increased steadily over the past 4 years. And the power supplies interlocks for the SSRF top-up operation will be also introduced in this paper.

THPO012	Using a High Precision Programmable DC Power Supply of TPS Magnet	power-supply, quadrupole, controls, sextupole	3358
	Y.S. Wong, J.C. Huang, K.-B. Liu, W.S. Wen NSRRC, Hsinchu, Taiwan
	Taiwan government had been announcement to set up a third-generation synchrotron radiation light source in February 2010. It should be installed with 10³² sets of magnet power supplies for the storage ring and 152 sets for the injector. In the storage ring, high precision DC power supply for 48 dipoles magnets , 240 quadrupole magnets and 168 sextupole magnets. The main windings of quadrupole and sextupole magnets are powered by individual power supplies. In the booster rings, one set of dynamic power supply for the dipole magnets and four sets for quadrupole magnets run at the biased 3Hz quasi sinusoidal wave. The Taiwan photon source (TPS) plan was completed indication national synchrotron radiation research central (NSRRC) technical capability to build at its present site in seven years a 3~3.3 GeV electron energy, 518 meter circumference, low-emittance synchrotron storage ring which will offer one of the world's brightest synchrotron x-ray sources, provide cutting-edge experimental facilities and novel multidisciplinary scientific research opportunities, enhance world-class academic research, as well as create Taiwan's scientific research marvels in the twenty-first century.

THPO013	Development of a DSP-based Digital Control Three Phase Shunt Active Power Filter for Magnet Power Supply System	controls, power-supply, simulation, sextupole	3361
	B.S. Wang, K.-B. Liu, Y.S. Wong NSRRC, Hsinchu, Taiwan
	There will be 240 quadruple and 168 sextuple magnet power supplies installed in TPS storage ring, power factor of these power supplies is an important issue to be concerned. A digital control three-phase shunt active power filter (APF) for quadruple and sextuple magnet power supplies is implemented and the power factor is better than 0.98. The APF power stage employs a three-phase switch-mode rectifier (SMR) to reduce the input current harmonics distortion and correct the power factor. The digital control circuit of the three-phase shunt active power filter is implemented by using a multi-channel 12 bits analog-to-digital converter、high resolution Pulse Width Modulated (PWM) and a TMS320F28335 digital signal processor (DSP). The system configuration is described in three function blocks include principle of compensation、design of the snubber protective circuit and control strategies. Finally, the feasibility and validity of proposed scheme is simulated with Matlab simulink and verified by the homemade digital control three-phase shunt active power filter.

THPO017	Improvement of Output Current Characteristics for Bira MCOR30 Correction Magnet Power Supply	controls, power-supply, HOM, feedback	3373
	J.C. Huang, K.-B. Liu, Y.S. Wong NSRRC, Hsinchu, Taiwan
	The correction magnet power supplies installed at the Taiwan light source (TLS) are Bira Systems’ MCRO 30 power modules, a full-bridge configuration power stage converting the unregulated DC bulk power into a bi-polar current source. The MCOR 30 is theoretically regulated under a very fine control method, with this control method the Bira MCOR 30 should overcome the zero crossover distortion of a standard H-Bridge PWM schemes is used and result in a low frequency noise signature on the output when the magnet current is close to zero. The PWM control circuitry embedded in MCOR 30 theoretically but not really fulfills the purpose what the MCOR 30 want to achieve. With a home-made PWM control circuitry installed into MCOR 30, the width of real pulses can smoothly drop to zero, the MCOR 30 could output current not only with a low frequency noise signature but also much with higher bandwidth of frequency response and much lower Total Harmonic Distortion no matter what output current is demanded.

THPO018	N+1 Redundancy Power Supply System by Paralleling Current Converter Modules with Digital Regulation Control	controls, power-supply, feedback, simulation	3376
	B.S. Wang, K.-B. Liu, Y.S. Wong NSRRC, Hsinchu, Taiwan
	The N+1 redundancy power supply system is fulfilled with adopting the Bira System MCOR30s as a platform, eight pieces of Bira MCOR 30 power converter boards are installed at crate 2512 and outputs are connected together, the output current of these paralleled eight Bira MCOR 30 power converters are regulated by an external homemade digital control circuit. With homemade digital control circuit, these paralleled eight Bira MCOR 30 power converter modules could deliver up to 240A/30V with ±20ppm precision and stability. The digital regulation control circuit of the N+1 redundancy power supply system is implemented by using a multi-channel DAC5868 16-bits digital-to-analog converter (DAC)、a high speed AD8382 18-bits analog-to-digital converter and a TMS320F28335 digital signal processor (DSP). The update reference voltage frequency of DAC is 83.3 kHz. A DCCT is used as the current feedback component and the output current ripple of the N+1 redundancy power supply system is lower than 20ppm which is beyond the requirement of current TLS quadruple and sextuple power supplies and qualified to be used in the future TPS facility.

THPO024	Development of a Non-Linear Kicker System to Facilitate a New Injection Scheme for the BESSY II Storage Ring	kicker, injection, vacuum, impedance	3394
	O. Dressler, T. Atkinson, M. Dirsat, P. Kuske HZB, Berlin, Germany H. Rast DELTA, Dortmund, Germany
	Top-Up injections without noticeable motion of the stored beam is a challenge. The common method of beam accumulation with a local bump formed by four independent pulsed dipole kicker magnets usually causes beam oscillations. The matching of the four independent kicker systems regarding pulse jitters and shapes is technologically limited. Afterward the beam excitation was reduced more when two kicker magnets on each side of the septum were powered in series by one pulser unit. An even more promising approach is to adopt an alternative injection method deploying a single non-linear kicker magnet with zero Bx,y-field in the center and an off-axis maximum, By, which is horizontally displaced by 10^-12 mm. There the injected beam gets kicked and looses half of its transverse momentum. Such a magnet was designed and built as a short in-vacuum magnet with a small vertical gap height. For first beam tests the kicker was placed in the second straight section after the injection point, and the 1.5 μs pulse was designed to deflect the 1.72 GeV beam by 1 mrad. In this paper, the calculations of the magnetic fields, the mechanical design as well as the electrical pulser circuit are described. *New injection scheme using a pulsed quadrupole magnet in electron storage rings, Kentaro Harada, PHYSICAL REVIEW SPECIAL TOPICS - AB 10, 123501 (2007)

THPZ011	Optimization of Chromatic Sextupoles in Electron Storage Rings Using Genetic Algorithms	sextupole, dynamic-aperture, resonance, emittance	3705
	Z. Duan IHEP Beijng, Beijing, People's Republic of China Q. Qin IHEP Beijing, Beijing, People's Republic of China
	Funding: Work supported by National Science Foundation of China contract 10725525. In order to suppress the head-tail instability, strong chromatic sextupoles are used in modern electron storage rings to correct large chromaticities due to small emittance or strong insertion quadrupoles to squeeze the bunch size at some places. However, the introduction of strong chromatic sextupoles also brings severe nonlinearity and might reduce dynamic aperture drastically. In the case of several sextupole families, the genetic algorithms are applied to find suitable configurations of sextupole strengths, directly maximizing dynamic aperture. A GeneRepair operator is introduced into the algorithm to correct chromaticities and optimize the dynamic aperture simultaneously in electron storage rings.

FRXAA01	Theory of Microwave Instability and Coherent Synchrotron Radiation in Electron Storage Rings	impedance, synchrotron, electron, shielding	3774
	Y. Cai SLAC, Menlo Park, California, USA
	Funding: This work was supported by Department of Energy Contract No. DE-AC02-76SF00515. Bursting of coherent synchrotron radiation has been observed and in fact used to generate THz radiation in many electron storage rings. In order to understand and control the bursting, we return to the study of the microwave instability. In this talk, we will report on the theoretical understanding, including recent developments, of the microwave instability in electron storage rings. The historical progress of the theories will be surveyed, starting from the dispersion relation of coasting beams, to the work of Sacherer on a bunched beam, and ending with the Oide and Yokoya method of discretization. This theoretical survey will be supplemented with key experimental results over the years. Finally, we will describe the recent theoretical development of utilizing the Laguerre polynomials in the presence of potential-well distortion. This self-consistent method will be applied to study the microwave instability driven by commonly known impedances, including that of coherent synchrotron radiation.
	Slides FRXAA01 [0.948 MB]

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MOXAA01

ALBA Synchrotron Light Source Commissioning

booster, linac, synchrotron, injection

1

D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

ALBA is a 3rd generation Synchrotron Light Source build in Barcelona, Spain. It is a 3 GeV Light Source with a circumference of roughly 270 m, an emittance of 4.4 nmrad and a design current of 400 mA. The storage ring has 24 straight sections from which 19 can be used for the installation of insertion devices, the rest will be used for injection, RF-cavities and diagnostic. The storage ring has been optimized for a high photon flux density for the users. The 3 GeV booster synchrotron with an emittance smaller the 10 nmrad is installed in the same tunnel. The pre injector is a 100 MeV Linac. The project started officially in 2004. The linac is operating since 2008, the booster since 2010 and the first commissioning phase for the storage ring will be finished in June 2011. This presentation gives an overview of the ALBA project with the emphasis on the results of the commissioning of the three accelerators Linac, booster synchrotron and storage ring.

Slides MOXAA01 [8.891 MB]

MOPC004

352.2 MHz HOM Damped Normal Conducting ESRF Cavity: Design and Fabrication

cavity, HOM, coupling, vacuum

68

V. Serrière, A.K. Bandyopadhyay, D. Boilot, L. Goirand, J. Jacob, B. Ogier, A. Triantafyllou
ESRF, Grenoble, France

Funding: This work, carried out within the framework of the ESRFUP project, has received research funding from the EU Seventh Framework Programme, FP7.
The ongoing ESRF upgrade included an option for an increase of the storage ring current from 200 to 300 mA, which has been tested successfully with the existing RF system. At this current level the HOM tuning of the existing five-cell copper cavities becomes extremely delicate and in view of a future reliable operation in user mode, new HOM free normal conducting cavities were developed at the ESRF. The design is based on the existing BESSY/ALBA cavity. However, several substantial modifications have been implemented and different fabrication processes elaborated to improve the design. Three operational prototypes will be delivered by three manufacturers in the coming months and will be fully tested on the ring. Although the 300 mA option has finally not been retained for the first phase of the ESRF upgrade, the aim is now to validate the new cavity design for a possible later increase in current.

MOPC045

Commissioning of the ALBA Storage Ring RF System

cavity, LLRF, HOM, pick-up

178

F. Pérez, B. Bravo, A. Salom, P. Sanchez
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

ALBA is a 3 GeV, 400 mA, 3rd generation Synchrotron Light Source that is under commissioning in Cerdanyola, Spain. The RF System has to provide 3.6 MV of accelerating voltage and restore up to 540 kW of power to the electron beam. For that six RF plants, working at 500 MHz, are foreseen. The RF plants include several new developments: DAMPY cavity; the normal conducting HOM damped cavity developed by BESSY and based in the EU design; six are installed. CaCo; a cavity combiner to add the power of two 80 kW IOTs to produce the 160 kW needed for each cavity. WATRAX; a waveguide transition to coaxial, specially designed to feed the DAMPY cavities due to the geometrical and cooling constrains. Digital LLRF; fully designed at ALBA using commercial components. This paper shortly describes these systems and reports their performance during the ALBA commissioning.

MOPC046

CaCo: A Cavity Combiner for IOTs Amplifiers

cavity, simulation, high-voltage, HOM

181

B. Bravo, F. Mares, F. Pérez, P. Sanchez
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
M.L. Langlois
ESRF, Grenoble, France

The ALBA storage ring uses six room temperature cavities; each one fed by two 80 kW IOTs amplifiers at 499.654 MHz. The power of the pair of transmitters is combined by a cavity combiner, CaCo. One of the design requirements of CaCo was that it continued working safely and with a good efficiency in the case of an IOT failure (asymmetrical mode). During the first asymmetric full power tests, in May 2010, with an active IOT and the other passive, the result was dramatic, the passive IOT broke in two parts after few hours of operation. This paper presents the experimental results and the electromagnetic field simulations of the asymmetrical operation mode of CaCo, i.e. one active IOT and the other passive, and analyze why the ceramic of the output tube of the passive IOT broke during the first performance of this mode. Also, it reports a possible solution to solve this problem.

MOPC051

The 100 MHz RF System for the MAX IV Storage Rings

cavity, LLRF, HOM, impedance

193

Å. Andersson, E. Elafifi, M. Eriksson, D. Kumbaro, P. Lilja, L. Malmgren, R. Nilsson, H. Svensson, P.F. Tavares
MAX-lab, Lund, Sweden
J.H. Hottenbacher
RI Research Instruments GmbH, Bergisch Gladbach, Germany
A. Milan
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
A. Salom
ELETTRA, Basovizza, Italy

The construction of the MAX IV facility has started and user operation is scheduled to commence 2015. The facility is comprised of two storage rings optimized for different wavelength ranges, and a linac-based short pulse facility. In this paper the RF systems for the two storage rings are described. The RF systems will be based on either tetrode or solid state amplifiers working at 100 MHz. Circulators will be used to give isolation between cavity and power amplifier. The main cavities are of normal conducting, entire copper, capacity loaded type, where the present cavities at MAX-lab has served as prototypes. For the MAX IV ring operation it is essential to elongate bunches, in order to minimize the influence of intra beam scattering on beam transverse emittances. For this, 3rd harmonic passive (Landau-) cavities are employed. These are of similar type as the main cavities, mainly because the capacity loaded type has the advantage of pushing higher order modes to relatively high frequencies compared to pill-box cavities. Digital low level RF systems will be used, bearing in mind the possibility of post mortem analysis.

MOPC078

Operation of Superconducting Cavities in a Fast Ramping Electron Storage Ring

cavity, HOM, impedance, acceleration

253

A. Roth, W. Hillert
ELSA, Bonn, Germany

Funding: Supported by German Research Foundation through SFB/TR 16.
The achievable maximum energy of a medium-sized electron accelerator is mainly limited by the accelerating voltage. Using superconducting (sc) cavities, the energy limitation can be shifted considerably. However, the operation of sc multi-cell cavities in a fast ramping storage ring causes additional problems which were investigated at the 3.5 GeV Electron Stretcher Accelerator ELSA. We studied the use of two 500 MHz sc cavities providing the necessary resonator voltage of up to 14 MV and replacing the normal conducting cavities of PETRA type. A large cavity coupling factor is required, so that using the existing 250 kW klystron, an internal beam of 50 mA can be accelerated up to 5 GeV. In addition, a fast detuning of the resonance frequency of the cavities must be implemented during beam injection and the energy ramp of 4 GeV/s. An appropriate 500 MHz structure is given by a five-cell cavity constructed for the JAERI-FEL-LINAC. Based on this geometry, HOM have been calculated from a numerical simulation. Since all monopole and a larger number of dipole HOM are well above the multibunch instabilities threshold, further studies about beam instabilities damping are essential.

MOPC127

Development of High RF Power Solid State Amplifiers at SOLEIL

cavity, power-supply, booster, klystron

376

P. Marchand, M.E. El Ajjouri, R. Lopes, F. Ribeiro, T. Ruan
SOLEIL, Gif-sur-Yvette, France

In SOLEIL, 5 solid state amplifiers provide the required 352 MHz RF power: 1 x 35 kW for the booster (BO) cavity and 4 x 190 kW for the 4 superconducting cavities of the storage ring (SR). Based on a design fully developed in house, they consist in a combination of a large number of 330W elementary modules (1 x 147 in the BO and 4 x 724 in the SR) with MOSFET transistors, integrated circulators and individual power supplies. After 5 years of operation, this innovative design has proved itself and demonstrated that it was an attractive alternative to the vacuum tube amplifiers, featuring an outstanding reliability and a MTBF > 1 year. In the meantime, thanks to the acquired expertise and the arrival of the 6th generation transistors, SOLEIL has carried out developments which led to doubling the power of the elementary module (700 W at 352 MHz and 500 MHz), while improving the performance in terms of gain, efficiency and thermal stress. This approach was also extended to frequencies from the FM to L band. The increasing interest for this technology has led SOLEIL to collaborate with several other laboratories and conclude a transfer of know-how with the French company, ELTA-AREVA.

MOPC130

High Power Solid State RF Amplifier Proposal for Iran Light Source Facility (ILSF)

cavity, booster, rf-amplifier, simulation

385

R. safian
IPM, Tehran, Iran
M. Jafarzadeh
ILSF, Tehran, Iran

Solid state RF amplifiers are being considered for an increasing number of accelerator applications. Their capabilities extend from a few kW of power to several hundred kilo watts and from frequencies less than 100 MHz to above 1 GHz. This paper describes the proposed general scheme for the high power solid state RF generator of the Iran light source facility (ILSF). The maximum expected power of the generator is 200 KW which is used for driving the storage ring cavities. Similar RF generator with lower output power can be used for driving the booster cavities.

MOPO002

Fast Orbit Correction for the ESRF Storage Ring

power-supply, feedback, diagnostics, controls

478

E. Plouviez, F. Epaud, J.M. Koch, K.B. Scheidt
ESRF, Grenoble, France

Today, at the ESRF, the correction of the orbit position is performed with two independent systems: one to deal with the slow movements and one to correct the motion in a range of up to 200Hz but with a limited number of fast BPMs and steerers. This later will be removed and one unique system will cover the frequency range from DC to 200Hz using all the 224 BPMs and the 96 steerers. Indeed, thanks to the procurement of the Liberas Brilliance and installation of new AC power supplies, it is now possible to access all the Beam positions at a frequency of 10 kHz and to drive a small current in the steerers in a 400Hz bandwidth. The first tests of correction of the beam position have been performed and will be presented. This new orbit correction system is also a powerful diagnostics system: the measurement and survey of the Ring's lattice parameters is possible thanks to the high measurement rate of very high resolution position data. Results of this will also be presented.

MOPO010

Orbit Feedback System for the MAX IV 3 GeV Storage Ring

feedback, vacuum, power-supply, simulation

499

M. Sjöström, J. Ahlbäck, M.A.G. Johansson, S.C. Leemann, R. Nilsson
MAX-lab, Lund, Sweden

The paper describes the current orbit correction system design for the 3 GeV storage ring at the MAX IV laboratory, a light source facility under construction in Lund, Sweden. The orbit stability requirements for the 3 GeV storage ring are tight at roughly 200 nm vertical position stability in the insertion device (ID) straight sections. To meet this the ring will be equipped with 200 beam position monitors (BPMs) and 380 dipole corrector magnets, 200 in the horizontal and 180 in the vertical plane. The feedback loop solution, one slow orbit feedback (SOFB) loop and one fast orbit feedback (FOFB) loop in fast acquisition mode at 10,000 samples/second, will be presented. The paper will also discuss the various boundary conditions specific to the MAX IV 3 GeV storage ring design, such as a Cu vacuum chamber, and the impact on the corrector design.

MOPO035

Stability of the Floor Slab at Diamond Light Source

site, insertion, insertion-device, target

562

J. Kay, K.A.R. Baker, W.J. Hoffman
Diamond, Oxfordshire, United Kingdom
I.P.S. Martin
JAI, Oxford, United Kingdom

A Hydrostatic Leveling System (HLS) has been installed at Diamond Light Source. 8 sensors have been positioned along a 60 metre portion of the floor of the Storage Ring and the Experimental Hall, stretching out along a typical beamline route from Insertion Device to sample. Results since June 2008 are presented comparing actual performance with the original specification as well as identifying movements associated with environmental factors.

MOPS007

Interference of CSR Fields in a Curved Waveguide

impedance, positron, damping, wakefield

604

D.M. Zhou, K. Ohmi
KEK, Ibaraki, Japan

CSR fields generated by a bunched beam passing through a series of bending magnets may interfere with each other due the reflections of outer chamber wall. This kind of multi-bend interference causes sharp peaks and long-range tail in the CSR impedance and wake potentials, respectively. Using a dedicated computer code, CSRZ, we calculated the longitudinal CSR impedance in the SuperKEKB positron damping ring for purpose of demonstration. It was found that multi-bend interference may enhance the CSR fields within a distance comparable to the bunch length, which is typically in the order of several millimeters. A simple instability analysis was performed and it suggested that multi-bend interference might play a role in the single-bunch instabilities of small electron/positron rings.

MOPS048

Microbunching Instability Studies at SOLEIL

electron, radiation, synchrotron, synchrotron-radiation

709

C. Evain, J. Barros, J.B. Brubach, L. Cassinari, M.-E. Couprie, G. Creff, M. Labat, A. Loulergue, L. Manceron, R. Nagaoka, P. Roy, M.-A. Tordeux
SOLEIL, Gif-sur-Yvette, France

Microbunching instability arises in storage rings when the number of electrons in a bunch exceeds a threshold value. Its signature, i.e. a strong and irregular emission of Coherent Synchrotron Radiation (CSR) in the Terahertz (THz) domain, is studied at SOLEIL on the AILES infrared beamline, with the storage ring tuned in a low-alpha configuration (used to get shorter electron bunch). The comparison of this observed THz CSR with numerical simulations of the longitudinal electron bunch dynamics, permits to put in evidence that during the instability a modulation appears and drifts in the longitudinal profile of the electron bunch. The understanding of this instability is important as it limits some operation of the storage rings. Indeed the induced fluctuations prevent the use of THz on the far IR beamline at high current per bunch. And in normal alpha operation this instability may spoil the electron/laser interaction effects used to get femtosecond and/or coherent pulse in storage rings (with slicing, Coherent Harmonic Generation or EEHG schemes on storage ring).

MOPS056

An Analytical Formula of the Electron Cloud Linear Map Coefficient in a Strong Dipole

electron, dipole, vacuum, simulation

733

T. Demma
INFN/LNF, Frascati (Roma), Italy
S. Petracca, A. Stabile
U. Sannio, Benevento, Italy
G. Rumolo
CERN, Geneva, Switzerland

Electron cloud effects have been indentified as one of the most serious bottleneck for reaching design performances in presently running and proposed future storage rings. The analysis of these effects is usually performed with very time consuming simulation codes. An alternative analytic approach, based on a cubic map model for the bunch-to-bunch evolution of the electron cloud density, could be useful to determine regions in parameters space compatible with safe machine operations. In this communication we derive a simple approximate formula relating the quadratic coefficient in the electron cloud density map to the parameters relevant for the electron cloud evolution in a strong vertical magnetic field. Results are compared with simulations with particular reference to the LHC dipoles.

MOPS065

Transverse Instability Studies at the ALBA Storage Ring

impedance, vacuum, single-bunch, kicker

751

T.F. Günzel
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

In the first phase of the ALBA storage ring operation 3 NEG-coated aluminum chambers, 2 in-vacuum undulators and one wiggler chamber will be installed. Under particular consideration of the multilayer character of these chambers and the injection kickers the thresholds of the transverse mode coupled instability(TMCI) were calculated using MOSES*. The thresholds 17.5mA/40.5mA vertical/horizontal leave a rather large operative margin. The detrimental effect of the NEG-coating on the TMCI is relatively limited and on the resistive wall instability is even negligible. As well the thresholds of the head-tail instability were computed as function of chromaticity. Also the incoherent tune shifts generated by the quadrupolar resistive wall wake fields due to the flatness of the vacuum chambers were calculated. The computed results have been compared to first measurements of the storage ring commissioning.
* Y.H.Chin, MOSES 2.0, CERN/LEP-TH/88-05

MOPS066

Collective Effects in the MAX IV 3 GeV Ring

impedance, cavity, damping, synchrotron

754

P.F. Tavares
MAX-lab, Lund, Sweden
T.F. Günzel
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
R. Nagaoka
SOLEIL, Gif-sur-Yvette, France

We present calculations of collective instability effects in the 3 GeV electron storage ring of the MAX IV facility currently under construction in Lund, Sweden. The storage ring is designed to deliver ultra-low emittance down to 0.24 nm rad so as to provide high brightness synchrotron radiation from undulators. This is achieved in a comparatively small machine (528 m circumference) through the use of a multi-bend achromat lattice and a compact magnet design featuring multi-purpose narrow gap magnet blocks. This design features small dispersion leading to low momentum compaction, which, together with the small circular (11 mm radius) chambers, poses a challenge to reach the design current (500 mA in 176 bunches) without exciting instabilities and degrading beam parameters due to the interaction with the machine impedance. Particularly important are multi-bunch resistive wall effects in the NEG coated copper chamber as well single-bunch instabilities driven by the broad-band impedance. A low RF frequency (100 MHz) and harmonic cavities are foreseen to lengthen the bunches and increase instability thresholds.

MOPZ012

The International Design Study for the Neutrino Factory

factory, target, proton, cavity

847

J.K. Pozimski, A. Kurup, K.R. Long
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
J.S. Berg
BNL, Upton, Long Island, New York, USA

The International Design Study for the Neutrino Factory (the IDS-NF) has recently completed the Interim Design Report* (IDR) for the facility as a step on the way to the Reference Design Report (RDR). The IDR has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents the present baseline design for the facility which will provide 10²¹ muon decays per year from 25 GeV stored muon beams. The facility will serve two neutrino detectors; one situated at source-detector distance of between 3000–5000 km, the second at 7000–8000 km. The conceptual design of the accelerator facility will be described and its performance will be presented. The steps that the IDS-NF collaboration has taken since the IDR was finalized and plans to take to prepare the RDR will also be presented.
* IDS-NF-020: https://www.ids-nf.org/wiki/FrontPage/Documentation?action=AttachFile&do=get&target=IDS-NF-020-v1.0.pdf
Submitted on behalf of the IDS-NF collaboration

TUODA01

Vertical Emittance Reduction and Preservation at the ESRF Electron Storage Ring

emittance, coupling, quadrupole, feedback

928

A. Franchi, J. Chavanne, F. Ewald, L. Farvacque, T.P. Perron, K.B. Scheidt
ESRF, Grenoble, France

In 2010 a campaign for the reduction and preservation of low vertical emittance at the ESRF electron storage ring was undertaken: values between 20 and 30 pm have been dramatically reduced to 3.5-4.5 pm, even during beam delivery. This improvement is the result of an increased measurement precision provided by the recently upgraded beam position monitoring system, a new correction algorithm, a larger number of correctors and two independent schemes for the automatic compensation of coupling induced by a few insertion devices whenever their gaps are moved by users during beam delivery. This paper summarizes the campaign's milestones and the results updated to the first half of 2011.

Slides TUODA01 [5.297 MB]

TUXB01

Methods and Tools to Simulate and Analyse Non-linear Dynamics in Electron Storage Rings

lattice, emittance, sextupole, quadrupole

937

L.S. Nadolski
SOLEIL, Gif-sur-Yvette, France

This talk will present the different approaches and tools that have been recently developed while trying to understand or predict the non-linear dynamics of electron storage rings. Different algorithms have been recently used at different places to optimize the sextupole tunings, while the refinement of the models of existing machines together with more accurate measurement techniques enable now to fully understand the limitations of such facilities specially in the presence of insertion devices.

Slides TUXB01 [7.624 MB]

TUOAB02

Simultaneous Long and Short Bunch Operation in an Electron Storage Ring - a Hybrid Mode based on Nonlinear Momentum Compaction

electron, synchrotron, octupole, photon

945

M. Ries, J. Feikes, A. Jankowiak, P.O. Schmid, G. Wüstefeld
HZB, Berlin, Germany

The generation of short pulses in electron storage rings is driven by different user groups like time resolved x-ray spectroscopy users or users of coherent synchrotron radiation. The required optics and operation conditions to generate this short bunches are worsening the experimental conditions, e.g. strongly reducing the average photon flux, for the regular user. Therefore short bunch operation is usually limited to dedicated user shifts. By controlling higher orders of the momentum compaction factor by higher multipoles it is possible to introduce a hybrid mode and simultaneously supplying long and short bunches*. The Metrology Light Source (MLS) has the means to control these higher orders**, therefore it is an ideal machine to investiate the feasibility of such a hybrid mode. Tracking results and first measurements will be shown.
* D. Robin et al., Proc. of EPAC08, p. 2100-2102, Genoa, Italy (2008).
** J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011).

Slides TUOAB02 [7.817 MB]

TUOAB03

Enlarging Dynamic and Momentum Aperture by Particle Swarm Optimization

lattice, sextupole, dynamic-aperture, simulation

948

Z. Bai, W. Li, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Particle swarm optimization (PSO) is a computational intelligence algorithm for global optimization. Obtaining adequate dynamic and momentum aperture is crucial for high injection efficiency and long beam lifetime in low emittance electron storage rings. Different from nonlinear driving terms optimization, we have made direct optimization of dynamic and momentum aperture by PSO algorithm. It is critical to make a criterion for comparison of dynamic and momentum aperture tracking results in the direct optimization procedure. Thus, in this paper we first propose a quantitative criterion of dynamic aperture. Then we apply PSO to the optimization of chromatic and harmonic sextupoles to find the optimum sextupole settings for enlarging the dynamic aperture. Taking the momentum aperture into consideration, we make joint optimization of dynamic and momentum aperture. Also, the momentum aperture has its quantitative criterion. As an example of application, the dynamic and momentum aperture of an FBA lattice studied in the design of storage ring of Hefei Advanced Light Source were optimized, and the results have shown the power of PSO algorithm.

Slides TUOAB03 [0.313 MB]

TUODB01

Progress of the Construction for the TPS Vacuum System

vacuum, photon, impedance, ion

976

G.-Y. Hsiung, C.K. Chan, C.H. Chang, C.-C. Chang, C.L. Chen, C.M. Cheng, Y.T. Cheng, S-N. Hsu, H.P. Hsueh, I.T. Huang, T.Y. Lee, I.C. Sheng, L.H. Wu, H.Y. Yan, Y.C. Yang, C.S. huang
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

Vacuum system for the 3 GeV Taiwan Photon Source (TPS) has been started the construction since 2010. The critical components such as the bellows and gate valves with rf-contact shielding, pulsed magnet kicker ceramic chambers, BPM, crotch absorbers, etc. have been manufactured and tested. Aluminum alloy (Al-) vacuum chambers for the arc-cells have been machined and undergoing the in-house welding. Mass production of the vacuum equipments including the ion gauges, ion pumps, NEG pumps, and gate valves, has been contracted out and partially delivering following the schedule of the cell assembling. Each cell, contains two short Al-straight chambers and two Al-bending chambers, has been started the assembling and on-site welding on the pre-aligned girders in clean room forming an one-piece vacuum vessel about 14 m in length following by the vacuum baking to the ultra-high vacuum. The conceptual design of the vacuum systems for the long straight sections, the concentric booster, and the transport lines, will be addressed. The progress of prototyping development and the status of construction for the TPS vacuum system will be described in this paper.

Slides TUODB01 [35.595 MB]

TUPC040

Modified Lattice of the Compton X-ray Source NESTOR

lattice, electron, sextupole, focusing

1087

A.Y. Zelinsky, P. Gladkikh, A.A. Kalamayko, I.M. Karnaukhov, A. Mytsykov, A.A. Shcherbakov
NSC/KIPT, Kharkov, Ukraine

NESTOR is Compton X-ray source that is under commissioning in NSC KIPT. One of the main parts of the facility is the middle energy storage ring (40-225 MeV). The storage ring has comprehensive lattice to provide low emittance, low beam size in the interaction point and big value of the energy acceptance. One of the NESTOR storage ring lattice feature is use of bending magnets of 0.5 m radius with combined focusing function. It leads to increasing of 3D magnetic field effects on electron beam dynamics. After NESTOR magnetic element manufacturing characteristics of element magnetic fields were measured and the effect of the real magnetic field distribution on beam dynamics was calculated. As a result, to provide project X-ray source characteristics the parameters of NESTOR storage ring lattice should be modified. The second reason for the lattice modification was the desire to increase the interaction point straight section length. The results of the beam dynamics simulation after lattice modification and optimization show that the storage ring will provide all project electron beam parameters. The results of the electron beam simulations are presented in the paper.

TUPC062

Electron Beam Energy Measurement at the Australian Synchrotron Storage Ring

electron, synchrotron, resonance, scattering

1138

M.J. Boland
ASCo, Clayton, Victoria, Australia
H. Panopoulos, R.P. Rassool, K.P. Wootton
The University of Melbourne, Melbourne, Australia

The technique of resonant spin depolarization was used to precisely measure the electron beam energy in the storage ring at the Australian Synchrotron. A detector and data acquisition system dedicated to the measurement were developed. Using the system, the long term energy stability of the storage ring was monitored and a mechanical realignment of the ring was clearly seen in the energy data. Details of the parameters used to optimize the measurement are also discussed.

TUPC072

Accurate Electron Beam Size Measurement at the Metrology Light Source

electron, photon, radiation, polarization

1165

R. Klein, G. Brandt, R. Thornagel
PTB, Berlin, Germany
J. Feikes, M. Ries, G. Wüstefeld
HZB, Berlin, Germany

For the operation of the Metrology Light Source (MLS)*, the dedicated electron storage ring of the Physikalisch-Technische Bundesanstalt (PTB), as the national primary radiation source standard from the near infrared to the vacuum ultraviolet spectral region, all storage ring parameters which are relevant for the calculation of the radiant intensity by the Schwinger equation have to be known absolutely with small uncertainties. For the measurement of the effective vertical electron beam size a Bragg polarimeter, operating at a photon energy of 1103 eV, has been designed and put into operation. This system also serves as a detection system for the image of the electron beam through a set of narrow slits. The results obtained with the new device are compared to those measured by an optical beam imaging system**.
* R. Klein et al., Phys. Rev. ST-AB 11, 110701 (2008).
** C. Koschitzki et al., Proc. IPAC10, 894-896 (2010).

TUPC075

Diagnostic Devices for Beam Intensity Measurement at FAIR

ion, synchrotron, diagnostics, antiproton

1174

M. Schwickert, T. Hoffmann, F. Kurian, H. Reeg
GSI, Darmstadt, Germany
R. Geithner, W. Vodel
HIJ, Jena, Germany
R. Neubert, P. Seidel
FSU Jena, Jena, Germany

Funding: Work supported by EU, DITANET, Project No. ITN-2008-215080.
Precise determination of beam intensity is important for any accelerator facility. At FAIR, the Facility for Antiproton and Ion Research presently in the planning phase at GSI, the requirements set by beam intensities in the various accelerators, storage rings and transport lines differ significantly. A set of beam diagnostic instruments is foreseen to detect the large variety of ion beams ranging from less than 10⁴ antiprotons up to high intensity of 5·10¹¹ uranium ions. This contribution presents an overview of destined current measurement devices, both intercepting, like scintillators, ionization chambers or secondary electron monitors, and non-intercepting current-transformer type devices. Ongoing developments are discussed for non-intercepting devices, i.e. a dc current transformer with large dynamic range and a cryogenic current comparator, purpose-built for the detection of lowest beam intensities at FAIR.

TUPC082

Beam Current Measurements at the TSR Heidelberg

ion, pick-up, acceleration, electron

1195

M. Grieser, S.T. Artikova, K. Blaum, F. Laux, J. Ullrich
MPI-K, Heidelberg, Germany

To conduct experiments using low energy ion beams at the TSR heavy ion storage ring, the beam deceleration process must be well understood. During deceleration of the beam the revolution frequency decreases, resulting in low current, which is difficult to measure with a common DC transformer. The number of particles in a bunch is determined by measuring the voltage signal in the time domain using a capacitive pick-up. If the ratio of bunch length and RF period does not change during the deceleration or acceleration, measuring the pick-up signal spectrum, where the signal is directly proportional to the number of particles in a bunch, is a more sensitive method. An alternative method is using a beam profile monitor (BPM) for determining the number of particles in the storage ring via ionization rate measurements of the residual gas. A summary of these different methods to determine the number of particles is presented.

TUPC085

Observation of Microwave Radiation using Low-cost Detectors at the ANKA Storage Ring

radiation, synchrotron, vacuum, optics

1203

V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller, M.J. Nasse, N.J. Smale
KIT, Karlsruhe, Germany
F. Caspers
CERN, Geneva, Switzerland
P. Peier
PSI, Villigen, Switzerland

Funding: Work supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320
Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed because the waveguide cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: The accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths above the waveguide cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually used in standard TV-SAT-receivers and are very cheap. We determined the time response of LNBs to be below 100 ns. The sensitivity of LNBs is optimized to detect very low intensity "noise-like" signals.

TUPC086

A Setup for Single Shot Electro Optical Bunch Length Measurements at the ANKA Storage Ring

laser, electron, synchrotron, radiation

1206

N. Hiller, E. Huttel, A.-S. Müller, A. Plech
KIT, Karlsruhe, Germany
F. Müller, P. Peier, V. Schlott
PSI, Villigen, Switzerland

Funding: Supported by the Initiative and Networking Fund of the Helmholtz Association under VH-NG-320. Sponsored by the German Federal Ministry of Education and Research under contract number 05K10VKC
Single shot electro optical bunch length measurements, in particular using spectral decoding, are foreseen for the ANKA storage ring. This will allow to resolve fast changes of bunch deformation and structure during the low alpha operation (2-15 ps rms bunch length). This technique uses a chirped laser pulse to probe the field induced birefringence in an electro optical crystal. The laser pulse is then analyzed in a single shot spectrometer. To obtain the birefringence modulation one can either use the near field of the electron bunch (placing the crystal close to the electron bunch in the UHV system of the storage ring), or the far field (coherent synchrotron radiation in the THz range at a THz-/IR-Beamline). The laser needs to supply: sufficient tunability of pulse length, a wide spectrum to allow for a sub-ps resolution. Additionally it must provide a mode-locked operation synchronized to the bunch revolution clock. For this purpose, a mode locked Ytterbium fibre laser system which operates at 10³⁰ nm has been developed at the Paul-Scherrer Institute in Switzerland. We give an overview over the experimental set up in the ANKA storage ring and the status of the project.

TUPC087

Filling Pattern Measurements at the ANKA Storage Ring

photon, electron, single-bunch, synchrotron

1209

B. Kehrer, N. Hiller, A. Hofmann, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale
KIT, Karlsruhe, Germany

For many accelerator physics studies, e.g. the investigation of coherent synchrotron radiation (CSR), a precise knowledge of the quantitative filling pattern (i.e. the number of electrons per bunch) is essential. This can be achieved by either using a linear detector (analog recording) or by employing the method of time-correlated single photon counting (TCSPC). At the ANKA storage ring both methods are in use. The analogue detection is based on the signal from a stripline or annular electrode, the TCSPC uses a Single Photon Avalanche Diode (SPAD). In this paper, we describe the experimental set-ups and present results of a comparison of the two techniques for single as well as for multi bunch filling patterns.

TUPC117

Embedded EPICS IOC Data Acquisition System for Beam Instability Research

betatron, feedback, wakefield, EPICS

1290

N. Zhang, Y.B. Leng
SSRF, Shanghai, People's Republic of China

Funding: This research is supported by National Natural Science Fund(No.Y155131061).
To be a part of beam diagnostics system in SSRF 3.5 GeV electron storage ring, a high performance oscilloscope is introduced to build a bunch by bunch data acquisition and processing dedicated system, which is mainly used to observe individual bunch position in transverse plane and bunch charge. By analysis of Betatron oscillation amplitude distribution and corresponding filling pattern, we hope to find phenomenon about multi-bunch Wakefield effect[1] on beam Betatron oscillation for beam instability research. The system is configured as a scope IOC, and integrated into the EPICS based control system. Application of this system and some data analysis results are also discussed in this paper.

TUPC154

Commissioning of the Detection System for a Supersonic Gas-jets Based Transverse Beam Profile Monitor

ion, extraction, simulation, electron

1392

M. Putignano, D. Borrows, A. Intermite
The University of Liverpool, Liverpool, United Kingdom
M. Putignano, M.R.F. Siggel-King, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: Work supported by STFC, the EU under GA-ITN-215080, the Helmholtz Association and GSI under VH-NG-328.
We present the commissioning results of the Micro-Channel-Plate (MCP) based, ion extraction and detection system currently in use for an experimental test stand aimed at demonstrating the operation of a least-interceptive transverse beam profile monitor based on a planar supersonic gas-jet. This monitoring design features least-interceptive operation under excellent vacuum conditions and provides fast acquisition of a fully bi-dimensional transverse profile. It bears application for ultra-low energy particle beams at future storage rings, but also for e.g. linacs at high currents and light source injectors. For instance, the Ultra-low energy Storage Ring (USR), part of the Facility for Antiproton and Ion Research (FAIR) in Germany will store antiprotons at energies of 20-300 keV. In this contribution, we report numerical simulations and experimental results obtained by calibration of the detection system with a low energy electron beam to demonstrate a 1 mm imaging resolution only limited by recoiling ion drift.

TUPC159

Energy Measurements with Resonant Spin Depolarisation at Diamond

electron, feedback, resonance, quadrupole

1404

I.P.S. Martin, M. Apollonio, R.T. Fielder, G. Rehm
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

A precise knowledge of the electron beam energy is critical for the accurate determination of many light source parameters, such as momentum compaction factor, natural chromaticity, energy stability and undulator spectra. In common with other facilities, a method of energy measurement based on resonant spin depolarisation has been developed at Diamond. In this paper we report on progress towards storage ring characterisation using this method, as well as describing the diagnostics developments that have enabled these measurements to be made.

TUPC163

Experimental Results from Test Measurements with the USR Beam Position Monitoring System

pick-up, simulation, vacuum, alignment

1416

J. Harasimowicz, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
J. Harasimowicz, I. Takov
The University of Liverpool, Liverpool, United Kingdom

Funding: Work supported by STFC, the EU under GA-ITN-215080, the Helmholtz Association and GSI under VH-NG-328.
A diagonal-cut capacitive pick-up (PU) was optimised for monitoring slow (v < 0.025c), long (~1 m) bunches consisting of only about 10⁶ antiprotons at the future Ultra-low energy Storage Ring (USR). Ultra-low noise (0.5 nV/Hz⁰.5) FET pre-amplifiers are used to allow detection of the weak signals generated in the PU plates. The amplified signals are then digitized by a 16-bit, 200 MS/s ADC and processed in a digital manner. The following contribution presents the beam monitoring system as it was tested with a stretched-wire method and compares the measurements with the results from 3D electromagnetic simulations.

TUPC166

Accelerator R&D in the QUASAR Group

antiproton, extraction, ion, diagnostics

1425

C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: Work supported by STFC, the EU under GA-PITN-215080, the Helmholtz Associations and GSI under VH-NG-328.
Since its start in 2007, the QUASAR Group’s research activities have grown considerably: Whilst the research program towards an ultra-low energy storage ring (USR) at the future facility for low-energy antiproton and ion research (FLAIR) is still the main research focus, developments of beam diagnostics tools for accelerators and lights sources, investigations into superconducting linear accelerators and medical applications, including the potential use of antiproton beams for cancer therapy purposes, widen the Group’s activities and international collaboration considerably. An overview of the QUASAR Group’s research achievements in accelerator science and technology to date is given in this contribution.

TUPO010

An Innovative Lattice Design for a Compact Storage Ring

lattice, radiation, synchrotron, synchrotron-radiation

1467

S. Sasaki, A. Miyamoto
HSRC, Higashi-Hiroshima, Japan

Funding: *This work is partially supported by Cooperative and Supporting Program for Researches and Educations in Universities sponsored by KEK.
We propose a new concept of lattice design for a compact light source storage ring. In a ring with this new scheme, the electron beam may have extremely longer design orbit than that of a conventional ring. In this ring, a design orbit closes after completing multiple turns. The lattice for realizing this exotic beam orbit can be made by placing conventional accelerator components such as bending magnets, quadrupole magnets, RF cavity and so forth in an appropriate manner onto a projected torus knot in the horizontal orbit plane. Due to an extended closed orbit length, the ring with this type of lattice has larger maximum stored charge if operated in multiple-bunch mode, and has longer bunch-to-bunch interval if operated in a single-bunch mode. Also, essential for a storage ring as the synchrotron light source, a larger number of straight sections may accommodate with many insertion devices. In addition, this new scheme may provide advantages for designing a oscillator-type free electron laser and coherent radiation light source.

TUPO013

Development of Pulse Width Measurement Techniques in a Picosecond Range of Ultra-short Gamma Ray Pulses

laser, photon, electron, scattering

1473

Y. Taira, M. Hosaka, K. Soda, N. Yamamoto
Nagoya University, Nagoya, Japan
M. Adachi, M. Katoh, H. Zen
Sokendai - Okazaki, Okazaki, Aichi, Japan
T. Tanikawa
UVSOR, Okazaki, Japan

Funding: This work was supported by Grants-in-Aid for Scientific Research from Japan Society for the Promotion of Science (JSPS).
We are developing the ultra-short gamma ray pulse source with the energy of MeV region based on laser Compton scattering at the 750 MeV electron storage ring, UVSOR-II. Gamma rays with pulse width of sub-picosecond range can be generated by injecting femtosecond laser pulses into the electron beam from the vertical 90-degree direction* because the electron beam circulating in the storage ring is focused more tightly in the vertical direction than in the longitudinal direction. The energy, intensity, and pulse width of the gamma rays can be tuned by changing the collision angle between the electron beam and the laser. We are developing pulse width measurement techniques of ultra-short gamma ray pulses at present. As the first step of the pulse width measurement, we used a fast response photodetector, Geiger-mode APD, the time resolution of which is few hundreds picoseconds. Although we cannot measure the pulse width of the gamma rays with sub-picosecond range using this detector, we could measure the pulse width of the gamma rays as 430 ps or less by measuring the timing of Cherenkov radiations generated from the gamma rays.
* Y. Taira et al., Nucl. Instrum. Meth. A, in press, 2010.

TUPO014

High-flux Gamma-ray Generation by Laser Compton Scattering in the SAGA-LS Storage Ring

laser, photon, survey, electron

1476

T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi
SAGA, Tosu, Japan

We constructed an experimental setup for high-flux gamma-ray generation by laser Compton scattering (LCS) in the SAGA-LS storage ring. The SAGA-LS is a synchrotron radiation (SR) facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring. We employed a CO2 laser having a wavelength of 10.6 micrometer to produce gamma-rays in the few MeV region in conjunction with the SR user time. The LCS gamma-ray up to the maximum energy of 3.5 MeV is generated via head-on collision between the laser photons and the 1.4 GeV stored beam. Since the energy acceptance of the storage ring is well above the maximum gamma-ray energy, the LCS experiment can be performed without reducing the beam lifetime. As a first step for high-flux gamma-ray generation, we use a small 10 W CO2 laser for beam test. The LCS event rate is designed to be 2·10⁸ ph/s with a beam current of 300 mA and a laser power of 10 W. A further increase of the LCS event rate in the order of 10¹0 ph/s is expected when a kW class laser is utilized. We report on the characteristics of the LCS gamma-rays observed in the low current beam test and an experimental result for evaluating the gamma-ray flux at a current of 300 mA.

TUPO017

Peculiarities of the Excitation of an Optical Resonator by an Electron Beam

electron, undulator, radiation, damping

1479

E.G. Bessonov, M.V. Gorbunkov, A.L. Osipov
LPI, Moscow, Russia
A.A. Mikhailichenko
CLASSE, Ithaca, New York, USA

The peculiarities of the optical resonator excitation by electrons in a FEL based on the Self-Stimulated Undulator Radiation at main and collateral synchronicity conditions are discussed*.
* E.G.Bessonov et al., Self-Stimulated Undulator Radiation and its Possible Applications, http://arxiv.org/ftp/arxiv/papers/10⁰⁹/1009.3724.pdf

TUPO018

Self-stimulated Undulator Klystron

undulator, FEL, electron, kicker

1482

E.G. Bessonov, A.L. Osipov
LPI, Moscow, Russia
A.A. Mikhailichenko
CLASSE, Ithaca, New York, USA

The Self Stimulated Undulator Klystron (SSUK) and its possible applications in the Particle Accelerator Physics, incoherent Self-Stimulated Undulator Radiation Sources (SSUR) and Free-Electron Lasers are discussed*.
* E.G.Bessonov et al., Self-Stimulated Undulator Radiation and its Possible Applications: http://arxiv.org/ftp/arxiv/papers/10⁰⁹/1009.3724.pdf

TUPS001

Upgrade of the ESRF Vacuum System

vacuum, controls, cathode, synchrotron

1515

M. Hahn, J.C. Biasci, H.P. Marques, A. Meunier
ESRF, Grenoble, France

The upgrade program of the ESRF concerns in terms of electron storage ring vacuum chambers mainly the insertion device (ID) sectors. Here the length available for the production of intense synchrotron light is being increased from five to six or even seven meters. The presence of canted ID sectors where two independent synchrotron light beams will be produced in the same straight section requires new quadrupole chambers compatible with the new geometry. A number of long insertion device vacuum chambers for the new ID sectors has already been produced by ESRF and coated with non-evaporable getter (NEG) material, a new generation of in vacuum undulators for the extended ID sections are under preparation. This paper outlines the status of the modification of the vacuum system and informs about consequences for the ESRF NEG coating activity and some recent improvements of the vacuum measurement and control system.

TUPS015

ALBA Storage Ring Vacuum System Commissioning

vacuum, photon, cavity, synchrotron

1551

E. Al-dmour, D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The ALBA booster and storage ring vacuum system installation has been done in 2009, followed by the installation of the RF cavities and the booster to storage transfer line in 2010. Early 2011, the first phase of insertion devices (ID) installation took place, with three narrow gap NEG coated vacuum chambers have been installed, for the use of two Apple-II undulators and one conventional wiggler. On 8th of March 2011, the storage ring commissioning started and it was marked with the achievement of the first turn in the storage ring on the 9th of March and on the 1st of April 2011, 100 mA of beam current has been accumulated. During this period the vacuum system conditioning took place with very good performance. The base pressure without beam was 4·10^-10 mbar and the average pressure with 100 mA was 7.7·10^-9 mbar. The results of the conditioning together with the latest developments are introduced.

TUPS016

Vacuum System Design for the MAX IV 3 GeV Ring

vacuum, synchrotron, lattice, radiation

1554

E. Al-dmour, D. Einfeld, J. Pasquaud, M. Quispe
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
J. Ahlbäck, M.J. Grabski, P.F. Tavares
MAX-lab, Lund, Sweden

We describe the conceptual design of the vacuum system of the 3 GeV electron storage ring in the MAX IV facility currently under construction in Lund, Sweden. The standard vacuum chambers are for the most part a cylindrical copper tube with 11 mm inner radius whereas stainless steel will be used at selected locations for beam position monitors, bellows and corrector vacuum chambers. In order to cope with the low vacuum conductance, distributed pumping will be provided through NEG coating of all chambers, including those in dipole magnets making MAX IV the first storage ring to be fully NEG coated. We present the mechanical and thermal design of these chambers and discuss the challenges involved in extracting insertion device radiation as well as coping with the heat load from both IDs and bending magnets in a machine with large bending radius, narrow chambers and tight mechanical tolerance requirements.

TUPS062

The Ground Testing of TPS Ground System

site, impedance, synchrotron, background

1677

T.-S. Ueng, J.-C. Chang, C.K. Kuan, Y.-C. Lin
NSRRC, Hsinchu, Taiwan

A ground grid of 4 rings and 62 vertical electrodes has been constructed for the TPS storage ring. The ground resistance was designed to be smaller than 0.2 ohms in order to give a good protection of the TPS electrical facility and personnel. In order to match the building construction schedule the TPS ground grid has been installed about 1/6 segment of the construction project each period. The ground impedance of each segment was measured right after the installation. The ground grid with the diameter of 200 m of outside ring and its low impedance value, also the limit testing space, challenged the measurement of ground resistance. Several different methods of ground testing have been used and the measured results are compared each other. These methods include fall-of-potential method, slope method, intersecting curves method and the test-current-reversal method. The final TPS ground impedance will be measured and compared with the calculation from combining the previous several segment measurements. The actual TPS ground resistance should have a smaller value than expected.

TUPS064

Construction Status of the Utility System for the 3GeV TPS Storage Ring

status, controls, booster, power-supply

1683

J.-C. Chang, J.-R. Chen, Y.-C. Chung, C.K. Kuan, K.C. Kuo, J.-M. Lee, Y.-C. Lin, C.Y. Liu, I. Liu, Z.-D. Tsai
NSRRC, Hsinchu, Taiwan

The construction of the utility system for the 3.0 GeV Taiwan Photon Source (TPS) has been contracted out in the end of 2009. The whole construction of the utility system is scheduled to be completed in the end of 2012. Total budget of this construction is about four million dollars. The utility system includes the electrical power, cooling water, air conditioning, compressed air and fire control systems. The TPS construction site is located adjacent to TLS. Some areas of TPS and TLS are overlapped. Under tight schedule, limit budget and geographic constrains, it is a challenge to complete the utility system construction of TPS on time, on budget, and to specification. This paper presents some main issues and status of the utility system construction for the TPS storage ring.

TUPS065

Design of the De-ionized Water Treatment for Taiwan Photon Source

controls, ion, status, photon

1686

Z.-D. Tsai, W.S. Chan, C.K. Kuan
NSRRC, Hsinchu, Taiwan

This work presents the water treatment design of Taiwan Photon Source (TPS). The system design is influenced by supplied water quality, water quantity and the selected process scheme. The system is composed of a pretreatment, make-up, and points-of-use filtration systems. The pretreatment system consists of an active carbon tower, a normally cartridge filter and a reversed osmosis (RO) unit. Furthermore, the make-up system consists of an ultraviolent (UV) TOC reduction unit and a ion-exchange resin unit. Following the water treatment process, the proposed system can provide high quality de-ionized water whose resistivity is better than 10 MΩ-cm at 25±0.1 degree C and dissolved oxygen is less than 10 ppb.

TUPS073

Top-Up Safety Simulations for the TPS Storage Ring

quadrupole, electron, sextupole, photon

1707

H.-J. Tsai, C.C. Chiang, P.J. Chou, C.-C. Kuo
NSRRC, Hsinchu, Taiwan

TPS is a 3 GeV third generation light source and operates in the top-up injection scheme. During the top-up injection, the beamline photon shutters are always open. To ensure the radiation safety of beamline experiments, we studied the possible particle leakage to ID and neighboring bending beamlines. The effects of errors on magnets and beam chamber alignments are investigated.

TUPS094

Girder and Support System for PLS-II Project

multipole, dipole, alignment, quadrupole

1759

H.-G. Lee, H.S. Han, J.Y. Huang, Y.-G. Jung, D.E. Kim, S.N. Kim, S.H. Nam, K.-H. Park, H.S. Suh
PAL, Pohang, Kyungbuk, Republic of Korea

Pohang Accelerator Laboratory (PAL) is planning to upgrade the Pohang Light Source (PLS) which is a 3rd generation light source operating since 1995. We have designed a new steel magnet girder using new schemes to achieve long-term mechanical stability, vibration suppression and precision adjusting system. Each half cell of girder is composed of three pieces, two multipole magnet girder(MMG) and one dipole magnet girder(DMG). The storage ring girders consist of 48 multipole magnet girders and 24 dipole magnet girders. The new girder systems have been fabricated and tested. Recently the girders have been installing and testing the moving mechanism in the storage ring. In this report, the design consideration for the PLSII girder and support systems are reported.

TUPZ006

Aperture Determination in the LHC Based on an Emittance Blowup Technique with Collimator Position Scan

beam-losses, emittance, injection, optics

1810

R.W. Assmann, R. Bruce, M. Giovannozzi, G.J. Müller, S. Redaelli, F. Schmidt, R. Tomás, J. Wenninger, D. Wollmann
CERN, Geneva, Switzerland
M. Alabau
IFIC, Valencia, Spain

A new method to determine the LHC aperture was proposed. The new component is a collimator scan technique that refers the globally measured aperture limit to the shadow of the primary collimator, expressed in σs of rms beam size. As a by-product the BLM response to beam loss is quantified. The method is described and LHC measurement results are presented.

WEPC001

Beam Based Sextupole Alignment Studies for Coupling Control at the ASLS

sextupole, quadrupole, coupling, alignment

1995

R.T. Dowd, Y.E. Tan
ASCo, Clayton, Victoria, Australia

Offsets in sextupole magnets can be a significant source of coupling in a storage ring and hinder efforts to minimize vertical emittance. Beam offsets in the sextupoles at the Australian Synchrotron Light Source were measured using a response matrix analysis in LOCO with differing magnets strengths. These results were used to obtain an estimate of offset in each sextupole as well as estimate quadrupole contributions to coupling.

WEPC024

LOCO in the ALBA Storage Ring

quadrupole, dipole, optics, coupling

2055

G. Benedetti, D. Einfeld, Z. Martí, M. Muñoz
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

ALBA is a 3 GeV 3rd generation light source which achieved first stored beam in February 2011, and will be commissioned during 2011. The ring comprises of 112 independent quadrupoles grouped in 14 families and 32 combined gradient dipoles powered in series. This paper reviews the process of recovering the design lattice and the symmetry of the machine, and the effects on orbit and lifetime. The main tool employ for this has been the LOCO implementation provided in the Matlab MiddleLayer. First results shows that the main effect on the symmetry is the difference between bending magnets. As this effect can not be compensated locally at present at the bendings, a global optics correction using all the quadrupoles is used.

WEPC033

Decoupling Problem of Weakly Linear Coupled Double Mini-beta-y Lattice of TPS Storage Ring

coupling, lattice, betatron, resonance

2076

H.-P. Chang, C.C. Chiang, M.-S. Chiu
NSRRC, Hsinchu, Taiwan

Three double mini-beta-y (DMBy) lattice design of the TPS storage ring is in progress to enhance the photon sources at three of the six long straight sections. For the estimation of Touschek beam lifetime, the TRACY code is used to calculate the momentum acceptance of the linear coupled TPS 3-DMBy lattice. The weak linear coupling was generated by adding some random skew quadrupoles at all quadrupole locations in order to create 1% coupling. Using the Teng’s symplectic rotation form in program may cause trouble in decoupling the one-turn coupled matrix. This report describes how we solve this decoupling problem and some useful references and comments are also presented.

WEPC034

High-level Application Programs for the TPS Commissioning and Operation at NSRRC

quadrupole, controls, target, EPICS

2079

F.H. Tseng, H.-P. Chang, C.C. Chiang
NSRRC, Hsinchu, Taiwan

For the Taiwan Photon Source (TPS) commissioning and operation we have developed more MATLAB-based application programs and tested them on the Taiwan Light Source (TLS). These additional applications built with the MATLAB Middle Layer (MML) include beta function measurement, dispersion function measurement, chromaticity measurement, chromaticity correction, and tune control. In this paper, we will illustrate what algorithms we use in these applications and show the test results. Especially, in order to get the first beam in the TPS commissioning, we adopt the RESOLVE algorithm for the beam steering and it has been built successfully in UNIX-like systems such as Mac OSX and different Linux versions. It can provide us some exercises of error finding and correction before the TPS commissioning in 2013.

WEPC049

Operation and Storage Ring Calibration with the Transverse Bunch-by-Bunch Feedback System at the Australian Synchrotron

feedback, sextupole, damping, synchrotron

2121

M.J. Boland, Y.E. Tan
ASCo, Clayton, Victoria, Australia
D.J. Peake, R.P. Rassool, K.P. Wootton
The University of Melbourne, Melbourne, Australia

The first operational experience with the transverse bunch-by-bunch feedback system for the storage ring shows a doubling of the lifetime and the ability to damp instabilities caused by IVU gap changes. The system was also used to calibrate the ring by doing simultaneous measurements on several single bunches with different bunch currents. Using the bunch-by-bunch system's capability to excite the beam to large amplitudes, the non-linear beam dynamics were also measured and compared with the model.

WEPC064

Long Term Beam Dynamics in Ultra-Low Energy Storage Rings

ion, antiproton, target, scattering

2166

A.V. Smirnov
MPI-K, Heidelberg, Germany
A.I. Papash, A.V. Smirnov
JINR, Dubna, Moscow Region, Russia
M.R.F. Siggel-King, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: "Work supported by STFC, the Helmholtz Association and GSI under contract VH-NG-328."
Electrostatic storage rings operate at very low energies in the tens of keV range and have proven to be invaluable tools for atomic and molecular physics experiments. However, earlier measurements showed strong limitations in beam intensity, a fast reduction in the stored ion current, as well as significantly reduced beam life time at higher beam intensities and as a function of the ion optical elements used in the respective storage ring. In this contribution, the results from studies with the computer code BETACOOL into the long term beam dynamics in such storage rings, based on the examples of ELISA, the AD Recycler and the USR are presented.

WEPC066

High Order Non-linear Motion in Electrostatic Rings

lattice, focusing, proton, simulation

2172

D. Zyuzin, R. Maier, Y. Senichev
FZJ, Jülich, Germany

The advantages of an electrostatic storage ring as compared to a magnetic ring are obvious from the point of view to search for the proton electric dipole moment (pEDM). However the magnetic and electrostatic fields have the different nature and, consequently, different features. In particular, particles moving in electrostatic field, can change their own kinetic energy as electrical field coincides with the direction of motion, which is not so for the magnetic field, where the force is always perpendicular to the direction of motion. The electrostatic rings found many applications in the atomic physics and partly the beam dynamics has been already investigated. However in EDM ring some additional specific features are added, which are considered in this paper.

WEPC069

Impact of Nonlinear Resonances on Beam Dynamics at the SPring-8 Storage Ring

injection, resonance, coupling, betatron

2181

M. Takao, J. Schimizu, Y. Shimosaki, K. Soutome
JASRI/SPring-8, Hyogo-ken, Japan

For a low emittance storage ring like high brilliant light sources, the improvement of nonlinear beam dynamics is necessary for the stable operation, or for providing large dynamic aperture and momentum acceptance for efficient injection and long Touschek lifetime. At the SPring-8 storage ring it is observed that injection efficiency is affected by the gap heights of the magnet arrays of the in-vacuum insertion devices. The fact that the injected beam of fundamentally oscillating in horizontal direction is limited by the vertical aperture means that coupling resonances influence the beam dynamics. To clarify the phenomena, we studied the nonlinear beam dynamics of transverse betatron motion by means of turn-by-turn method. Then, we found some nonlinear coupling resonances, such as the one by skew sextupole field, are excited to enhance vertical oscillation and to deteriorate the injection efficiency. By analyzing these results, we developed measures to suppress the effect of the nonlinear coupling resonances and to improve the injection efficiency.

WEPC109

Emittance Optimization Using Particle Swarm Algorithm*

emittance, lattice, quadrupole, synchrotron

2271

Z. Bai, W. Li, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

In this paper we use a swarm intelligence algorithm, particle swarm optimization (PSO), to optimize the emittance directly. Some constraint conditions such as beta functions, fractional tunes and dispersion function, are considered in the emittance optimization. We optimize the strengths and positions of quadrupoles to search low emittances. Here an FBA lattice studied in the design of the Hefei Advanced Light Source storage ring is used as the testing lattice. The PSO is shown to be beneficial in the optimization.

WEPC116

A Matrix Presentation for a Beam Propagator including Particles Spin

collider, controls, heavy-ion, scattering

2283

M. Kosovtsov, S.N. Andrianov, A.N. Ivanov
St. Petersburg State University, St. Petersburg, Russia

Particles beam dynamics in magnetic and electrical fields with spin is discussed. This approach provides a constructive method of matrix presentation derivation for a beam propagator in magnetic and electrical fields. The beam propagator is evaluated in according to the well-known Lie algebraic tools. But in contrast to traditional approaches matrix presentation for Lie propagators bases on two-indexes matrices. This approach permit to apply all of matrix algebra opportunities and advantages in contrast with the tenzor presentation based on multi-indexes description. The necessary computation can be realized in symbolic (using computer algebra codes as Mathematica, Maple, Maxima and so on). The corresponding symbolic objects itself can be stored in special databases and used then in numerical computing. Parallel and distributed conception is well acceptable with the suggested matrix formalism. Some symbolic and numerical results are discussed for problems of long term evolution of particles with spin.

WEPC123

Numerical Algorithm based on the PDE Method for the Solution of the Fokker-Planck Equation

simulation, pick-up, kicker, impedance

2298

M. Dolinska
NASU/INR, Kiev, Ukraine
C. Dimopoulou, A. Dolinskii, F. Nolden, M. Steck
GSI, Darmstadt, Germany

Funding: Work supported by HIC for FAIR
This paper discus a fast and accurate algorithm for numerical solution of Fokker-Planck equation based on the solution of the parabolic Partial Differential Equations (PDE), where the Crank–Nicholson scheme is used. The stability, convergence and round-off errors of the algorithm are studied. The numerical results on Fokker–Planck equation solution with PDE method are compared with other numerical methods. Using the PDE solver, we will be able to predict the stochastic cooling process of notch filter in storage rings.

WEPC156

Virtual Power Supply Control Environment for the TPS Project

power-supply, controls, EPICS, quadrupole

2349

Y.-S. Cheng, Y.-T. Chang, J. Chen, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao, C.Y. Wu
NSRRC, Hsinchu, Taiwan

The Taiwan Photon Source (TPS) is the latest generation of 3 GeV synchrotron light source which has been under construction since 2010. The control system infrastructure of TPS project is based upon the EPICS framework. In order to develop the control applications before power supplies of magnets delivered, it is necessary to set up the virtual control environment to develop high level application programs for the power supplies of magnets in advance. The high level application programs include operation process, degauss process and etc. for power supplies of magnet. The soft-IOCs (Input Output Controller) and various database records are needed to be built to simulate the power supply control environment. In addition, the operation interfaces of power supply will be designed and integrated according to location properties. The efforts will be described at this report.

WEPC159

A Python Tracking Code and GUI for Control Room Operations

controls, lattice, status, dipole

2358

M.T. Heron, J. Rowland
Diamond, Oxfordshire, United Kingdom

Considerable use has been made in recent years of accelerator physics modelling and online tools under Matlab. These have demonstrated the benefits of operating in a rich integrated environment and further given good portability across projects and operating systems. As a possible alternative to Matlab, Diamond has been evaluating options based on Python. Python together with the Numpy libraries and Qt Graphics provides an environment which offers a lot of the functionality of Matlab. This paper presents these developments, which include a tracking code, symplectic integrator, twiss and response matrix together with a GUI interface.

WEPO013

Septum and Kicker Magnets for the ALBA Booster and Storage Ring

kicker, injection, booster, vacuum

2421

M. Pont, R. Nunez
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
E. Huttel
KIT, Karlsruhe, Germany

At the ALBA Synchrotron light source 6 kicker and 3 septa magnets are installed for beam injection and extraction. A 100 MeV beam coming from the linac is injected on axis into the Booster. The full energy (3 GeV) beam is extracted from the booster and injected into the Storage Ring, where 4 kicker magnets bring the stored beam close to the septa. All septa are direct driven out-of-vacuum magnets with C shape iron laminated yoke. The magnets are excited by a full sine approx. 300 μs pulse length; the nominal field is 0.15/0.84/0.9 T (booster injection/extraction/storage-ring-injection). The stray field seen by the stored beam is less than 1 μT. The booster kicker magnets are in-vacuum magnets with C-ferrite yoke. The magnets are excited by a 0.4 μs flat top pulse; the nominal field is 0.03/0.04 T (booster injection/extraction). The storage ring kickers have a C-ferrite yoke and a 0.4 μm Ti coated ceramic vacuum chamber. The excitation is done by 6 μs half sine; the nominal field is 0.13 T. The paper will present the design of the elements and their magnetic characteristics. First results of their behaviour during commissioning will also be discussed.

WEPO015

MAX IV 3 GeV Storage Ring Prototype Magnet

dipole, simulation, magnet-design, lattice

2427

M.A.G. Johansson, L.-J. Lindgren
MAX-lab, Lund, Sweden
B. Anderberg
AMACC, Uppsala, Sweden

The MAX IV facility, currently under construction, will consist of a 3 GeV storage ring, a 1.5 GeV storage ring, and a full energy injector/SPF/FEL driver. The magnet design for the 3 GeV storage ring is conceptually identical to the MAX III storage ring magnets, with all magnet elements within each cell machined into one solid iron block. A prototype of a matching cell magnet block has been manufactured and mechanical and magnetic field measurements have been performed.

WEPO016

Design of the MAX IV/Solaris 1.5 GeV Storage Ring Magnets

lattice, ion, simulation, dipole

2430

M.A.G. Johansson
MAX-lab, Lund, Sweden

The MAX IV facility, currently under construction in Lund, Sweden, will consist of a 3 GeV storage ring, a 1.5 GeV storage ring, and a full energy injector/SPF/FEL driver. The Solaris facility, which will be built in Krakow, Poland, will use an identical 1.5 GeV storage ring, injected at 500 MeV. The magnet design for the 1.5 GeV storage ring is conceptually identical to the MAX III and the MAX IV 3 GeV storage ring magnets, with several magnet elements machined into one solid iron block. Detailed design has been done in Opera3D, with a model of the full magnet block being set up and simulated, and iterated against the lattice design.

WEPO020

Magnetic Field Inspection and Analysis of Multipole Lattice Magnets using a Rotating-coil Measurement System*

multipole, quadrupole, sextupole, synchrotron

2442

J.C. Jan, C.-H. Chang, Y.L. Chu, T.Y. Chung, C.-S. Hwang, C.Y. Kuo, F.-Y. Lin
NSRRC, Hsinchu, Taiwan

A precise rotating-coil measurement system (RCS) was constructed to characterize the field quality and field center of multipole lattice magnets of Taiwan Photon Source (TPS). The mechanical center of magnets is determined by the two references of the magnet-feet and the RCS system is used to characterize the field center. The location of the magnetic field center is quantitatively accurate to better than 20 micro-meter in the horizontal direction; the granite support height of the RCS system is accurate within 5 micro-meter after artificial polishing. The measurement reproducibility of the field center was better than 10 micro-meter when the magnets were reinstalled. The relative accuracy of the multipoles components is better than 2×10^-5. This paper reports the details of the bench construction and the unit composition. The field center with RCS measurement will be compared and discussed with the 3D-coordinate-measuring machine. The multipole errors obtained from RCS will be compared with a Hall-probe measurement system.

WEPS005

Investigation of Intrabeam Scattering in the Heavy Ion Storage Ring TSR

ion, bunching, electron, scattering

2490

S.T. Artikova, M. Grieser, J. Ullrich
MPI-K, Heidelberg, Germany

Intrabeam scattering (IBS) is a multiple scattering effect between stored beam particles. It leads to diffusion in all three spatial dimensions and thus, causes an expansion of the whole beam. IBS plays an important role in the equilibrium diameter of a low-velocity, electron-cooled ion beam. IBS effects for coasting and bunched 12C⁶⁺ ion beams at an energy of 73.3 MeV were studied using the TSR heavy ion cooler storage ring. Experimental results of the IBS rates are presented.

WEPS030

Ion Optics Alignment in the Electrostatic Double Storage Ring DESIREE

alignment, quadrupole, ion, optics

2547

P. Löfgren, M. Blom, F. Hellberg, L. Liljeby, A. Simonsson
MSL, Stockholm, Sweden
P. Reinhed
Stockholm University, Stockholm, Sweden

DESIREE is a cryogenic electrostatic double storage ring under construction at Stockholm University. The two rings have similar circumference, 8.8 m and a common straight section for merged beam experiments. In each ring the ions are guided by two 160° cylindrical deflectors and four 10° deflectors and focused by four quadrupole doublets. In terms of ion optics alignment the quadrupoles are the most important factor for the ion beam acceptance and the goal is to align all quadrupoles with precision of 0.1 mm. DESIREE is constructed as a double walled cryostat with an inner and an outer vacuum chamber. All optical elements are mounted directly on the bottom of the inner chamber. For positioning of the ion optics, the bottom plate is prepared with a number of footprints where each footprint consists of four small machined surfaces that define the height and two alignment holes that define the lateral position. The optical elements were aligned on the bottom plate using a portable measuring device in combination with a level instrument. In this work we describe the alignment procedure in detail and report on the overall precision obtained and the consequence for the ion beam.

THPC001

Progress Towards Implementation of Top-up at the Australian Synchrotron

injection, radiation, photon, interlocks

2904

G. LeBlanc, P. Bennetto, M.J. Boland, S. Costantin, R.T. Dowd, Y.E. Tan, D. Zhu, E.D. van Garderen
ASCo, Clayton, Victoria, Australia

The Australian Synchrotron Light Source has enjoyed several years of stable operations with a high degree of availability. It is now time to move towards top-up operations to improve the stability and integrated flux of the photon beam. This paper describes the steps that have been taken and what remains to be done in order to implement top-up injection as the normal operation mode for the first user runs of 2012.

THPC002

Implementation of a Low-Emittance Optics for the LNLS UVX Storage Ring

optics, emittance, quadrupole, lattice

2907

F. H. de Sá, L. Liu, X.R. Resende
LNLS, Campinas, Brazil

In this report we describe the theoretical optimization and implementation of a low-emittance optics for the LNLS UVX storage ring. The emittance is reduced by letting the dispersion be distributed everywhere while keeping the low vertical beta feature. The optimization strategy is based on a series of quadrupole strength scans and selection of points satisfying a number of criteria. The new mode reduces the emittance from 100 nm.rad to 40 nm.rad, including the effects of the already installed insertion devices, and keeps the working point in the same quadrant as the present operation BBY6T mode. Tests have shown a reduction of approximately 20% in the horizontal and vertical beam sizes in the middle of the dipoles, in agreement with the theoretical emittance reduction.

THPC005

First Measurements with a Kicked Off Axis Bunch for Pseudo Single Bunch Mode Studies at SOLEIL

kicker, single-bunch, closed-orbit, synchrotron

2912

L.S. Nadolski, J.-P. Lavieville, P. Lebasque, A. Nadji, J.P. Ricaud, M.G. Silly, F. Sirotti
SOLEIL, Gif-sur-Yvette, France

At SOLEIL, the time resolved French community benefits of single bunch operation few weeks a year. Meanwhile most of the multi-bunch filling pattern based experiments are not possible due to the low photon flux. Following the pioneer work performed at ALS*, a new operation mode is under study at SOLEIL where the storage ring is filled up with a special hybrid mode: ¾ multibunch filling pattern and a single bunch with higher current in the last ¼. The so-called pseudo single bunch-filling pattern is obtained if the closed orbit of the single bunch is not the same as the one of the other bunches. Preliminary results are presented where the pinger magnet time impulse response has been significantly reduced while its frequency was increased from 3 Hz up to 1 kHz. This magnet is used as an additional corrector magnet to change only the single bunch closed orbit. First experimental results observed at one interested beamline are also discussed.
* S. Kwiatkowski et al., “'CAMSHAFT' Bunch Kicker Design for the ALS Storage Ring", Proc. of EPAC2006, THPLS114, p. 3547, (2006).

THPC006

Experiments to Measure Electron Beam Energy using Spin Depolarization Method on SOLEIL Storage Ring

polarization, electron, beam-losses, synchrotron

2915

J.F. Zhang, L. Cassinari, M. Labat, A. Nadji, L.S. Nadolski, D. Pédeau
SOLEIL, Gif-sur-Yvette, France

The electron beam energy on SOLEIL storage ring was successfully measured using spin depolarization method after several attempts over the past few years. The experimental results demonstrate that the effective polarization was 91.3%±3% and polarization time was 17±2.3 minutes as expected from the simulation using SLIM code. The beam was depolarized using an AC shaker and the depolarization was monitored using DCCT and beam loss monitors. The beam energy was measured with accuracy up to a few 10^-5.

THPC007

Laser Electron Interaction Simulation for the Femtosecond Bunch Slicing on SOLEIL Storage Ring

laser, electron, wiggler, simulation

2918

J.F. Zhang, M.-E. Couprie, M. Labat, A. Loulergue, A. Nadji
SOLEIL, Gif-sur-Yvette, France

The interaction of an electron bunch and a laser in a wiggler (modulator) to generate a femtosecond slice is simulated for the slicing project on SOLEIL storage ring, using a code based on Monte-Carlo method and GENESIS. The results from these two codes are consistent with the theoretical values. The maximum modulated energy of the electron bunch and the number of electrons above a certain limit are studied for different wiggler and laser parameters. The transport of the 6D distribution of the sliced bunch from the modulator to the radiators are simulated using AT (Accelerator Toolbox) and ELEGANT, with synchrotron radiation on and taking into account the collective effects of the sliced bunch core.

THPC009

Performance and Upgrade of the ESRF Light Source

emittance, undulator, cavity, vacuum

2924

J.-L. Revol, J.C. Biasci, J-F. B. Bouteille, J. Chavanne, F. Ewald, L. Farvacque, A. Franchi, G. Gautier, L. Goirand, M. Hahn, L. Hardy, J. Jacob, J.M. Koch, M.L. Langlois, G. Lebec, J.M. Mercier, T.P. Perron, E. Plouviez, K.B. Scheidt, V. Serrière
ESRF, Grenoble, France

The European Synchrotron Radiation Facility (ESRF) is now fully engaged in a large Upgrade Programme of its infrastructure, beamlines and X ray source. In this context, a first set of 10 insertion device straight sections are being lengthened from five to six metres; a number of them will be operated with canted undulators. The insertion devices are themselves subject to an ambitious development programme to fulfil the scientific requirements. The Radio Frequency system upgrade has started with the replacement of the booster klystron-based transmitter by high power solid state amplifiers, and the development of HOM damped cavities operating at room temperature. A completely new DC-AC orbit stabilization system using 224 BPMs and 96 orbit steerers is currently being commissioned. The upgrade is conducted while keeping, and even improving, routine performance for the user service. In particular the recent installation of new skew quadrupole power supplies allows routine operation with ultra low vertical emittance. This paper reports on the present operation performance of the source, highlighting recent developments and those still to come.

THPC013

THz Studies at a Dedicated Beamline at the MLS

radiation, electron, synchrotron, synchrotron-radiation

2933

R. Müller, A. Hoehl, A. Serdyukov, G. Ulm
PTB, Berlin, Germany
J. Feikes, M. Ries, G. Wüstefeld
HZB, Berlin, Germany

The Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute is operating the low-energy electron storage ring Metrology Light Source (MLS) in Berlin-Adlershof in close cooperation with the Helmholtz-Zentrum Berlin. The MLS is designed and prepared for a special machine optics mode (low-alpha operation mode) based on a sextupole and octupole correction scheme, for the production of coherent synchrotron radiation in the THz region*. At the MLS two bending magnet beamlines dedicated to the use of IR and THz synchrotron radiation are in operation: the MLS-IR beamline optimized for the NIR to FIR, and a dedicated THz beamline optimized for the FIR/THz spectral range**. Low-alpha operation optic modes for different ring energies, 250 MeV, 350 MeV, 450 MeV and 630 MeV are available. We compare the THz spectra taken in the different low-alpha modes and discuss the results.
* J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011).
** R. Müller et al., J. Infrared Milli Terahz Waves, in press (2011), DOI: 10.10⁰⁷/s10762-011-9785-6.

THPC021

Status of Bunch Deformation and Lengthening Studies at the ANKA Storage Ring

radiation, diagnostics, cavity, photon

2951

N. Hiller, A. Hofmann, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller
KIT, Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
At the ANKA storage ring (Karlsruhe, Germany) we use a Hamamatsu synchroscan streak camera to study the current dependent bunch lengthening and deformation effects . Previously the camera was used at an IR port, being available only occasionally. In October 2010, a dedicated “beam line” for the streak camera became operational. It is designed to have minimum dispersion and sufficient flux in the optical range at which the camera is most sensitive. This allows us to measure bunch profiles for a single bunch with a charge of less than 15 pC (40 μA), previously more than 55 pC were required to obtain a comparable signal. Along with the design and built-up, we present further measurements of bunch length and shape for different momentum compaction factors, RF voltages, beam energies and bunch charges to provide a complete bunch length map of the low alpha mode at ANKA.

THPC024

Lattice Candidates for the ILSF Storage Ring

lattice, emittance, dipole, synchrotron

2957

H. Ghasem
IPM, Tehran, Iran
D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
F. Saeidi
ILSF, Tehran, Iran

Iranian Light Source Facility (ILSF) is a new third generation synchrotron light source which is currently in design and will build in Iran. It will provide a high photon flux density to cover requirements of experimental science in several fields. Regarding to the proposed budget and in order to produce high quality X-ray pulses with several photon beamlines as a request of users, it is decided to design a very low emittance (ε<5nm-rad) storage ring with a typical beam intensity of 400 mA and circumference in the range of 280 m to 320 m. A number of design options with different lattice structure types, circumferences, etc., are explored and we present two designed lattice candidates of the ILSF storage ring. The associated Accelerator Physics issues are discussed.

THPC025

Booster Design for ILSF

booster, synchrotron, dipole, electron

2960

H. Ghasem
IPM, Tehran, Iran
E. Ahmadi
ILSF, Tehran, Iran
D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

A full energy 3 GeV booster synchrotron has been designed to boost electron beam to the target energy of 3 GeV for the proposed third generation synchrotron light source (ILSF) that will be constructed in Iran. The primary goal of the ILSF booster is to design a synchrotron which can deliver a small emittance (ε<30 nm-rad), while at the same time has a low cost in construction. In order to design lattice for the booster, two configurations for booster have been considered. In the first configuration, booster is designed based on locating in a separate tunnel as 3 GeV storage ring inside the ring and in the second configuration, the booster is optimized for placing inner to the ring with one shared wall as service area of ILSF storage ring. Several types of lattice with various circumferences have been explored for the booster synchrotron in each configuration and this paper presents results of linear and nonlinear optimization of the main designed lattice for booster in both configurations.

THPC027

Top-up Operational Experience at Elettra

injection, booster, radiation, controls

2966

E. Karantzoulis, A. Carniel, S. Krecic
ELETTRA, Basovizza, Italy

Since May 2010 Elettra, the third generation Italian light source, operates regularly for users at both 2 and 2.4 GeV in top-up. In this paper the experience during more than a year of operation in top-up at both user energies is discussed and the machine up time statistics presented and compared with the before top up period.

THPC028

A Proposal of Short X-ray Pulse Generation from Compressed Bunches by mm-wave iFEL in the SPring-8 Upgrade Plan

wiggler, injection, electron, simulation

2969

M. Masaki, K. Fukami, C. Mitsuda, T. Watanabe
JASRI/SPring-8, Hyogo-ken, Japan

In the SPring-8 upgrade plan, short pulse options are prepared for time-resolved experiments of pico-second order with high repetition rate. The best scenario is that selected bunches have equilibrium bunch length of 1 ps or less. A mm-wave storage-ring iFEL may be one possible solution for it. If resonant wavelength of the FEL is a few millimeters, which is about ten times longer than typical short bunch length of 0.3 mm corresponding to 1 ps, almost all electrons of a bunch can be confined in one valley of ponderomotive potentials formed by the FEL mechanism. The system consists of a helical wiggler with period length of several meters and a mm-wave resonator. Numerical simulations with coherent synchrotron radiation effect at bunch charge of 479 pC show that an ultra-short injection bunch is trapped in a mm-wave “bucket” and kept shorter than 1 ps (r.m.s.) even after twice the longitudinal damping time from the injection. The ultra-short bunches need to be injected from the XFEL linac. XFEL-to-Storage Ring beam transport line is designed to suppress dispersions which cause bunch lengthening. Tracking calculations show promising results for bunch qualities at the transport line.

THPC029

Ultra-low Emittance Light Source Storage Ring Consisting of 5-Bend Achromat Cells with Four Long Straight Sections

lattice, emittance, undulator, wiggler

2972

K. Tsumaki
JASRI/SPring-8, Hyogo-ken, Japan

The 6 GeV ultimate storage ring (USR) consisting of ten bend achromat cells has been proposed* and applied it to the SPring-8 Storage ring**. It has the same circumference as the SPring-8 storage ring, but does not have four long straight sections, where the SPring-8 storage ring does. The cell length is twice of that of the SPring-8 storage ring and the number of cell is half of the SPring-8. The photon beam line positions would deviate from those of the existing one. To avoid these problems, we designed a storage ring that has four long straight sections and same cell number. The cell is changed from ten bend achromat to five bend achromat and the cell length is shortened to 30 m which is the same length of the SPring-8 storage ring unit cell. The total ring consists of 44 five bend achromat cells and four long straight section cells. The emittance is 10⁴ pm and it will reduce to less than 50 pm by radiation damping of wigglers and undulators. The brightness is expected to be more than 10²2 phs/s/mm²/mrad² in 0.1%BW with 200 mA beam current.
* K. Tsumaki, N. Kumagai, NIM A 565 (2006) 394.
** K. Tsumaki, N. Kumagai, Proc. of EPAC06, THPLS035, p. 3362 (2006).

THPC030

Design of a BeamTransport Line from the SACLA Linac to the SPring-8 Storage Ring

lattice, emittance, linac, beam-transport

2975

K. Tsumaki, K. Fukami, T. Watanabe
JASRI/SPring-8, Hyogo-ken, Japan
S. Itakura, N. Kumagai
RIKEN/SPring-8, Hyogo, Japan

The SPring-8 Angstrom Compact Free Electron Laser (SACLA) linac has high beam qualities. The normalized emittance is less than 1 mm.mrad and the bunch length is less than 100 fs. If this high quality beam is injected to the SPring-8 storage ring, many interesting experiments can be done. On the other hand, the upgrade of the SPring-8 storage ring is under contemplation. The dynamic aperture of the new storage ring is expected to be so small that the small emittance beam is required to keep high beam injection efficiency. The SACLA linac beam also fulfills this requirement. For these reasons, it was decided to connect the SACLA linac and the SPring-8 storage ring. Since there is already an injection transport line from the SPring-8 synchrotron to the storage ring, the new transport line from the linac to this transport line has been constructed*. We designed the three types of magnet lattice for the new transport line; FODO, Double Bend Achromat and Triple Bend Achromat lattice. Emittance growth and bunch lengthening are calculated for each lattice and the beam qualities are compared. In this paper, lattice design and the comparison of the beam quality for each lattice are described.
* C. Mitsuda et al., this conference.

THPC031

Measurement of Longitudinal Dynamics of Injected Beam in a Storage Ring

injection, simulation, synchrotron, booster

2978

T. Watanabe, T. Fujita, M. Masaki, K. Soutome, S. Takano, M. Takao, K. Tamura
JASRI/SPring-8, Hyogo-ken, Japan

Experimental observation of longitudinal dynamics of injected beam in a storage ring has been demonstrated. Since the injected beam undergoes synchrotron oscillation in a longitudinal phase space, two projected values, i.e., a bunch duration and an energy spread, oscillate at twice the synchrotron frequency. At SPring-8, the initial energy spread (~0.126%) at the injection goes up and down until it reaches the equilibrium energy spread (~0.11%). If the injection timing should not be optimized, an asymmetrically enhanced oscillation could distort the injection efficiency. The observation of such an oscillation helps make sure that no significant injection loss occurs. More importantly, the scheme is expected to enable us to observe non-linear longitudinal dynamics of ultra-short bunches injected from the XFEL linac; the bunches are in near future going to be transferred from the linac to the storage ring via 600-meter long transports, in which strong coherent synchrotron radiation and other high peak-current effects will not be ignorable. Experimental results obtained by a dual-scan streak camera and other devices as well as numerical simulations will be presented.

THPC034

Post-earthquake Recovery of PF Ring and PF-AR

injection, vacuum, survey, alignment

2984

T. Honda, T. Aoto, S. Asaoka, K. Endo, K. Haga, K. Harada, Y. Honda, M. Izawa, Y. Kobayashi, A. Mishina, T. Miyajima, H. Miyauchi, S. Nagahashi, N. Nakamura, T. Nogami, T. Obina, T. Ozaki, C.O. Pak, H. Sakai, S. Sakanaka, H. Sasaki, Y. Sato, K. Satoh, M. Shimada, T. Shioya, M. Tadano, T. Tahara, T. Takahashi, R. Takai, Y. Tanimoto, K. Tsuchiya, T. Uchiyama, A. Ueda, K. Umemori, M. Yamamoto
KEK, Ibaraki, Japan

When the unprecedented scale of earthquake occurred in Japan on the afternoon of March 11, 2011, PF ring and PF-AR, two synchrotron light sources in KEK, also suffered various damages. At PF ring, a formed bellows in a wall current monitor was broken, and atmospheric air rushed into the beam duct. At PF-AR, which is installed in the underground tunnel, the alignment of the ring magnets seemed to be disordered to an order of ten mm. At both rings, a lot of electronics racks and toolboxes in the control rooms or in the experimental halls were tilted or tipped over. It was extremely fortunate that the user operation had just been stopped on the morning of that day, and all the gate valves in the rings and to the beam lines had already been closed for the scheduled shutdown. A wide area blackout took place at the big earthquake, and the electric power for the accelerator was interrupted over the next two weeks because of temporal shortage of the electricity in the eastern part of Japan. In April, we could start detailed investigation of machine damages and repair works towards recommissioning of the rings before the summer and resumption of the user operations in the autumn.

THPC037

Accelerators of the Central Japan Synchrotron Radiation Facility Project (II)

synchrotron, booster, electron, linac

2987

N. Yamamoto, M. Hosaka, A. Mano, H. Morimoto, K. Takami, Y. Takashima
Nagoya University, Nagoya, Japan
Y. Hori
KEK, Ibaraki, Japan
M. Katoh
UVSOR, Okazaki, Japan
S. Koda
SAGA, Tosu, Japan
S. Sasaki
JASRI/SPring-8, Hyogo-ken, Japan

Central Japan Synchrotron Radiation (SR) Facility Project is making progress for the service from FY2012. The construction of SR building is almost completed in the Aichi area of Japan, and the installs of accelerators will start in a few week. The key equipments of our accelerators are an 1.2 GeV compact electron storage ring that is able to supply hard X-rays and a full energy injector for top-up operation. The beam current and natural emittance of the storage ring are 300 mA and 53 nmrad. The circumference is 72 m. The magnetic lattice consists of four triple bend cells and four straight sections. The bending magnets at the centers of the cells are 5 T superconducting magnets and the critical energy of the SR is 4.8 keV. The injector consists of a 50 MeV linac and a booster synchrotron with the circumference of 48 m. To save construction expenses, the injector is built at inside of the storage ring. More than ten hard X-ray beam-line can be constructed. One variable polarization undulator will be installed in the first phase. The top-up operation will be introduced as early as possible.

THPC042

Status and Development of the SAGA Light Source

laser, controls, undulator, linac

2996

T. Kaneyasu, Y. Iwasaki, S. Koda, Y. Takabayashi
SAGA, Tosu, Japan

The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring, and has been stably providing synchrotron light since 2006. The annual failure time is less than 1% of the user time in the recent two years. Three insertion devices are installed in the storage ring: an APPLE-II undulator, a planar type undulator (Saga Univ.) and a 4 T superconducting wiggler (SCW). The SCW contains a hybrid three-pole magnet; the main pole of the magnet is surrounded by superconducting coils while side poles are normal conducting magnets. The main pole of the SCW is cooled by a GM cryocooler, which allows the SCW be operated without liquid helium. Since the installation in March 2010, the SCW has been operated stably. To control the ID parameters during the user time, a feed-forward correction system which minimizes the ID effects on the emittance coupling was developed. The laser Compton Gamma-rays were generated by using a CO2 laser and were used for beam energy measurement. In addition, research works on the beam lifetime and interaction between electron beam and crystal, and development of a multipole magnet are in progress.

THPC044

Operation and Performance Upgrade of the Soleil Storage Ring

undulator, vacuum, photon, feedback

3002

A. Nadji, P. Brunelle, M.-E. Couprie, J.-C. Denard, J.-M. Filhol, J.-F. Lamarre, P. Lebasque, A. Loulergue, P. Marchand, L.S. Nadolski, R. Nagaoka, M.-A. Tordeux
SOLEIL, Gif-sur-Yvette, France

SOLEIL delivers photons to 24 beamlines. Up to 22 very diverse insertion devices (IDs) are now installed on the storage ring, and 4 more will come by summer 2011, including a Cryogenic undulator and an electromagnetic/permanent magnet helical undulator, both designed and built at SOLEIL. Work is continuing on beam dynamics and magnetic corrections to reduce the nonlinear effects of all these IDs. A new optics incorporating an additional quadrupole triplet in one long straight section has been successfully tested and will be put in operation by fall 2011. A new coupling correction will also be implemented to maintain the ratio of the vertical to the horizontal emittances at 1% for any IDs configuration. The electron beam orbit stability has been significantly improved reaching a residual noise of 300 nm RMS. Photon LIBERA modules of X-BPM located on the bends, will be integrated soon in the orbit feedback loops. 4905 hours have been delivered in 2010 to the beamlines with an availability of 96.3%. The user operation with the maximum current of 500 mA is foreseen to start by fall 2011, after the completion of the radiation safety tests of the beamlines.

THPC052

Progress Towards Top-up Operation at SSRF

injection, radiation, controls, photon

3008

Z.T. Zhao, H.H. Li, L. Yin, W.Z. Zhang
SINAP, Shanghai, People's Republic of China

The Shanghai Synchrotron Radiation Facility (SSRF) has been in operation for user experiments in decay mode since May 2009. In the meantime various activities to prepare top-up operation at SSRF, including safety analysis and simulation, dedicated instrumentations and interlocks, control software, radiation measurements, injection optimization and top-up operation tests, have been carried out. In this paper, the progress towards top-up operation at SSRF is described together with its achieved performance.

THPC054

Project Status of the Polish Synchrotron Radiation Facility Solaris

linac, synchrotron, cavity, radiation

3014

C.J. Bocchetta, P.P. Goryl, K. Królas, M. Mlynarczyk, M.J. Stankiewicz, P.S. Tracz, Ł. Walczak, A.I. Wawrzyniak
Solaris, Krakow, Poland
J. Ahlbäck, Å. Andersson, M. Eriksson, M.A.G. Johansson, D. Kumbaro, S.C. Leemann, L. Malmgren, J.H. Modéer, P.F. Tavares, S. Thorin
MAX-lab, Lund, Sweden
E. Al-dmour, D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

Funding: European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Polish synchrotron radiation facility Solaris is being built at the Jagiellonian University in Krakow. The project is based on an identical copy of the 1.5 GeV storage ring being concurrently built for the MAX IV project in Lund, Sweden. A general description of the facility is given together with a status of activities. Unique features associated with Solaris are outlined, such as infra-structure, the injector and operational characteristics.

THPC057

Operation of the ALBA Injector

linac, booster, emittance, injection

3023

M. Pont, U. Iriso, R. Muñoz Horta, F. Pérez
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The ALBA injector made of a 100 MeV linac, operating at 110 MeV, and a full energy (3 GeV) booster synchrotron has been routinely in operation since October 2010. The stability of the linac and of the booster on reliability and performance is examined. Also results on the beam performance obtained with the installed diagnostic equipment will be discussed.

THPC058

The MAX IV Synchrotron Light Source

linac, emittance, lattice, vacuum

3026

M. Eriksson, J. Ahlbäck, Å. Andersson, M.A.G. Johansson, D. Kumbaro, S.C. Leemann, F. Lindau, L.-J. Lindgren, L. Malmgren, J.H. Modéer, R. Nilsson, M. Sjöström, J. Tagger, P.F. Tavares, S. Thorin, E.J. Wallén, S. Werin
MAX-lab, Lund, Sweden
B. Anderberg
AMACC, Uppsala, Sweden
L.O. Dallin
CLS, Saskatoon, Saskatchewan, Canada

The MAX IV synchrotron radiation facility is currently being constructed in Lund, Sweden. It consists of a 3 GeV linac injector and 2 storage rings operated at 1.5 and 3 GeV respectively. The linac injector will also be used for the generation of short X-ray pulses. The three machines mentioned above will be descibed with some emphasis on the effort to create a very small emittance in the 3 GeV ring. Some unconventional technical solutions will also be presented.

THPC059

Recent Improvements to the Lattices for the MAX IV Storage Rings

lattice, injection, optics, dipole

3029

S.C. Leemann
MAX-lab, Lund, Sweden

Construction of the MAX IV facility started early this year. The facility will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production of x-rays while the 1.5 GeV ring will serve UV and IR users. Recently, the lattices for the storage rings in the MAX IV facility were updated. In the 3 GeV storage ring the vertical beam size in the long straights has been reduced. The lattice of the 1.5 GeV storage ring has been updated to take into account first results from detailed magnet and vacuum system designs. Additionally, a new injection method to facilitate commissioning of the storage rings has been studied. This paper summarizes the changes made in the lattices and the effect of these modifications.

THPC061

Comparison of Linear Optics Correction Means at the SLS

optics, quadrupole, betatron, closed-orbit

3032

M. Aiba, M. Böge, J.T.M. Chrin, N. Milas, T. Schilcher, A. Streun
PSI, Villigen, Switzerland

The experimental determination of linear optics is a fundamental prerequisite to achieving a high performance storage ring. In order to further enhance SLS performance and to simulataneously reveal the limitations of the various techniques, we perform a systematic study of linear optics optimization using various independent methods. These include an analysis of the orbit reponse (LOCO), turn-by-turn data, and the response of the tune, whose correction is accomplished using the standard SLS procedure of varying the quadrupole strengths. A comparison of results from these procedures, which use fully independent observables, provides us with a valuable cross-check. For example, the betatron phase advances between BPMs, which is independent of BPM calibration, confirms the optics correction as determined from LOCO. The linear optics are hence better optimized, and these procedures, LOCO in particular, further serve to expose any previously hidden mis-calibration of parameters e.g. from BPMs and corrector magnets. Systematic errors from turn-by-turn data could also be vastly reduced by a better synchronization of the BPM triggers with the electron beam.

THPC063

A 2.9 Tesla Room Temperature Superbend Magnet for the Swiss Light Source at PSI

power-supply, dipole, vacuum, synchrotron

3038

A.L. Gabard, D. George, M. Negrazus, L. Rivkin, V. Vrankovic
PSI, Villigen, Switzerland
Y. Kolokolnikov, P. Vobly
BINP SB RAS, Novosibirsk, Russia

The Swiss Light Source (SLS) at the Paul Scherrer Institute (PSI) in Villigen, Switzerland, is a 3rd generation synchrotron light source. With an energy of 2.4 GeV, it provides high brightness photon beams for research in materials science, biology and chemistry. The SLS storage ring contains 36 room temperature bending magnets, all of which produce light for experimental use; at the design energy of 2.4 GeV, they have a maximum magnetic field of 1.4 Tesla. Light is produced along the entire bending arc but can only be transferred to the external experimental facilities from selected short portions of the beam path. In cooperation with the Budker Institute for Nuclear Physics (BINP) in Novosibirsk, Russia, three of these magnets were replaced with new room temperature magnets with short regions of high magnetic field up to 2.9 Tesla. This enabled the production of intense light beams at shorter wavelengths than from the existing magnets. The critical energy of the 2.9 T magnet is 11.1 keV, compared to the 5.4 keV of the normal bend. This paper describes the design, including the multiple restraints, together with the measurement and commissioning of these so-called superbends.

THPC064

Design Study of Low Emittance Lattice for Taiwan Light Source at 1 GeV

emittance, lattice, dynamic-aperture, wiggler

3041

C.Y. Lee
NTHU, Hsinchu, Taiwan
C.C. Chiang, P.J. Chou
NSRRC, Hsinchu, Taiwan
S.-Y. Lee
IUCEEM, Bloomington, Indiana, USA

We explored the possibility that the existing TLS storage ring to be operated at 1 GeV as a high brightness VUV light source after the completion of 3 GeV Taiwan Photon Source. To increase the spectral brightness, we need to reduce the beam emittance in the storage ring as much as possible. We first pursue the lowest emittance which is possible without altering the existing hardware configuration. The theoretical minimum emittance that could be achieved at 1 GeV for non-achromatic lattice is 3.8 nm-rad. However, this could not be achieved without introducing harmonic sextupoles. Preliminary results of low emittance lattice without harmonic sextupoles in TLS storage ring will be presented.

THPC069

Studies to Optimize the Diamond Light Source Booster Synchrotron as a 100 MeV Storage Ring

booster, quadrupole, synchrotron, linac

3053

C. Christou, M.T. Heron, J. Rowland
Diamond, Oxfordshire, United Kingdom
S. Gayadeen
University of Oxford, Oxford, United Kingdom

The injection chain for the Diamond Synchrotron Light Source consists of a 100 MeV Linac and 3 GeV booster synchrotron. These were commissioned in 2005 and 2006 respectively, and have provided acceptable performance as an injector since then. To advance a programme of work in evaluating and optimizing new control algorithms for orbit stability on the Diamond Storage Ring it was decided to use the booster synchrotron as a test platform by operating it in DC mode at 100 MeV. In support of this work and to improve the operational performance of the booster a series of studies have been carried out to better understand and characterize it. This work and the results will be presented.

THPC070

An Automated Statistical Analysis Package for the Study of Synchrotron Light Source Operation

cavity, beam-losses, monitoring, synchrotron

3056

C. Christou, C.P. Bailey, V.C. Kempson, V.J. Winter
Diamond, Oxfordshire, United Kingdom

Machine faults and interruptions to user beam at Diamond Light Source are recorded in a Fault Log Database (FLDB) running under Microsoft Access. The scope of numerical analysis in Access is limited, and so an advanced data analysis package has been written in Matlab to exploit the powerful numeric functions available in this environment to automatically analyze machine faults and summarize data for reliability reports. Figures of merit such as mean time between failure (MTBF), mean time to repair (MTTR), total up time and total number of faults over the machine as a whole and by technical group can be calculated, and more advanced Pareto and Weibull analyses can be instantly generated. Data is presented for Diamond Light Source both for the latest year of operation and since user beam began in 2007, and the impact of different technical groups, in particular the storage ring RF, is considered. Failure distributions and the underlying hazard functions are produced and compared with statistical models to highlight deviations from randomly occurring events and to quantify changes in failure probability with time.

THPC079

Echo-enabled Harmonic Generation at DELTA

undulator, laser, electron, bunching

3074

R. Molo, M. Bakr, H. Huck, M. Höner, S. Khan, A. Nowaczyk, A. Schick, P. Ungelenk, M. Zeinalzadeh
DELTA, Dortmund, Germany

Funding: Supported by DFG, BMBF, and the Federal State NRW
We present conceptual studies of the realization of the echo-enabled harmonic generation (EEHG) technique proposed by G. Stupakov* as an upgrade of the present coherent harmonic generation (CHG) project at the DELTA storage ring**. EEHG allows to reach shorter wavelengths compared to the CHG scheme. In addition to the optical klystron used for CHG, a third undulator is needed for a second energy modulation of the electron bunch, followed by an additional strong dispersive section. Installing these insertion devices requires a new long straight section in the storage ring and a new lattice configuration.
* G. Stupakov Phys. Rev. Lett. 10², 074801 (2009)
** A. Schick et al., this conference

THPC123

Injector Layout and Beam Injection into Solaris

injection, linac, gun, klystron

3173

A.I. Wawrzyniak, C.J. Bocchetta
Solaris, Krakow, Poland
S.C. Leemann, S. Thorin
MAX-lab, Lund, Sweden

Funding: European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Solaris synchrotron radiation storage ring to be built in Krakow, Poland is based on the MAX IV 1.5 GeV design. The injector will be a linear accelerator and its components identical to those for the MAX IV project, however, injection is not at full energy and the injector layout is different. The linac and transfer line layout, optics and injection scheme into the storage ring is presented and an analysis of accumulation before energy ramping is discussed.

THPC137

Low Emittance Booster Design for CANDLE Storage Ring

booster, emittance, injection, synchrotron

3209

G.S. Zanyan, B. Grigoryan, K. Manukyan, A. Sargsyan, V.M. Tsakanov
CANDLE, Yerevan, Armenia

The progress in synchrotron based research made the top up operation mode of storage rings as the most attractive option both from the beam lifetime and the user points of view. To provide reliable operation of the facility at top-up injection mode the full energy low emittance new booster ring for 3 GeV CANDLE storage ring is designed. The compact synchrotron magnets with integrated quadrupole and sextupole components are used. The new design provides 20 nm emittance at the top energy with sufficient dynamic aperture and optimal optical properties at straight section for effective extraction. The complete design of the new booster and beam dynamics issues during the energy ramping are presented.

THPC140

Design, Tuning and Results of the Pulsed Magnetic Systems for the Beam Injection in the SOLEIL Storage Ring Operated in ‘Transparent’ Top Up Mode

septum, kicker, injection, vacuum

3215

P. Lebasque, R. Ben El Fekih, M. Bol, J. Da Silva Castro, A. Hardy, C. Herbeaux, J.-P. Lavieville, A. Loulergue, J.L. Marlats, D. Muller, G. Renaud, J.P. Ricaud
SOLEIL, Gif-sur-Yvette, France

From the beginning, the SOLEIL Storage Ring was designed to operate in Top Up injection mode. So all equipments involved have been specified to generate as small as possible beam perturbations of the stored beam during the electron beam injection. This concerns many aspects of the design and realization of the injection pulsed magnets (kickers and septa), their vacuum chambers, pulsed power supplies and timing electronics. Despite quite satisfactory results of pulsed magnetic measurements in labs, a still too large perturbation was observed on the e^- beam orbit during the Storage Ring commissioning. Therefore a strong work of systematic measurements, analysis of each phenomena, tuning or modification of each device was led until reaching rather good and acceptable performances. This paper will present the results obtained. At this stage, the Storage Ring beam orbit is sufficiently stable in Top Up injection mode so that it is almost transparent to the 24 beam lines, even for the most sensitive ones. After a summary of the main significant topics, we present the developments foreseen to further improve the performances and make a new step towards a “perfect” Top Up injection.

THPC144

The Construction Status of Beam Transport Line from XFEL-linac to SPring-8 Storage Ring

beam-transport, lattice, linac, alignment

3224

C. Mitsuda, N. Azumi, T. Fujita, K. Fukami, H. Kimura, H. Ohkuma, M. Oishi, Y. Okayasu, M. Shoji, K. Tsumaki, T. Watanabe
JASRI/SPring-8, Hyogo-ken, Japan
M. Hasegawa, Y. Maeda, T. Nakanishi, Y. Tukamoto, M. Yamashita
SES, Hyogo-pref., Japan
N. Kumagai, S. Matsui
RIKEN/SPring-8, Hyogo, Japan

The beam transport line from XFEL-linac to SPring-8 storage ring is now under construction to use the ultra short bunched electron beam at the storage ring. The newly constructed line is about 300 m, which is just a half of the whole path from the XFEL linac to the storage ring. The beam extracted from XFEL-linac is guided to the beam transport tunnel connected to the matching section of booster synchrotron bending by 55.2 degrees horizontally and by 10.0 degrees vertically. A double-bend based lattice was adopted to reasonably suppress emittance growth and bunch lengthening. Supposing a bunch length and horizontal emittance at the exit of the XFEL-linac are estimated about 100 fs and 0.04 nmrad respectively, it is expected that the current beam emittance in storage ring is improved to about 0.4 nmrad and almost same bunch length including coherent synchrotron radiation effect. In 2010, the construction of extracting part from XFEL-linac was completed and we finished the installation and alignment of main components. The conceptual design and construction status of transport line will be presented with the emphasis on the detail magnet design and the fabrication.

THPC147

TPS SR Kicker Prototype Installation Status*

kicker, injection, high-voltage, vacuum

3230

Y.-H. Liu, C.K. Chan, C.-S. Chen, Y.L. Chu, K.H. Hsu, H.P. Hsueh, C.K. Kuan, C.Y. Kuo, C.-S. Yang
NSRRC, Hsinchu, Taiwan

The purpose of this paper is to illustrate the installation sequence of TPS SR kicker. Because of adding the rotation function in row direction, the position of every component of kicker must be very precise. The kicker magnet and EMI enclosure were fastened on the rotation motor plate which could rotate ±3.0 mrad. The ceramic chamber remain fixed on the bottom plate in order to let the bellow stress free during rotation. After installation, the inductance measurement and the high voltage breakdown test were also tested. The experimental results showed the good uniformity and reached the expected request. The field mapping and EMI prevention schemes will be tested in the future.

THPC149

Development of PrFeB Cryogenic Undulator (CPMU) at SOLEIL

undulator, cryogenics, vacuum, permanent-magnet

3233

C. Benabderrahmane, P. Berteaud, N. Béchu, L. Chapuis, M.-E. Couprie, J.P. Daguerre, J.-M. Filhol, C. Herbeaux, A. Lestrade, M. Louvet, J.L. Marlats, K. Tavakoli, M. Valléau, D. Zerbib
SOLEIL, Gif-sur-Yvette, France

A R&D programme for the construction of a 2 m long 18 mm period CPMU is under progress at SOLEIL. The cryogenic undulator will provide photons in the region of 1.4 to 30 keV. It will be installed in the next few months on the long straight section (SDL13) of the storage ring, and could be used later on to produce photons for the NANOSCOPIUM beamline. The use of PrFeB which features a 1.35 T remanence (Br) at room temperature enables to increase the peak magnetic field at 5.5 mm minimum gap, from 1.04 T at room temperature to 1.15 T at a cryogenic temperature of 77 K. Praseodymium was chosen instead of Neodymium magnetic material, because it is more resistant against the appearance of the Spin Reorientation Transition. Different corrections were performed first at room temperature to adjust the phase error, the electron trajectory and to reduce the multipolar components. The mounting inside the vacuum chamber enables the fitting of a dedicated magnetic measurement bench to check the magnetic performance of the undulator at low temperature. The results of the magnetic measurements at low temperature and the comparison with the measurement at room temperature are reported.

THPC156

Performance of the PETRA III APPLE II Undulator

undulator, multipole, closed-orbit, optics

3254

J. Bahrdt, W. Frentrup, A. Gaupp, M. Scheer
HZB, Berlin, Germany
K. Balewski, J. Keil, A. Schöps, M. Tischer
DESY, Hamburg, Germany

A 5m-long APPLE II undulator has been built in collaboration between Helmholtz-Zentrum Berlin and DESY Hamburg. Magnetic field measurements after the final shimming in the laboratory are presented. The device has been installed in the storage ring and machine studies have been performed. The tune shifts in the elliptical and the inclined mode are in agreement with predictions from theory. The dynamic field integrals have successfully been minimized in the storage ring with so-called L-shims (rectangular iron sheets) which are placed at the undulator center at the magnet edges.

THPC171

Performance of ID at ALBA

vacuum, wiggler, undulator, insertion

3299

J. Campmany, J. Marcos, V. Massana
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The new synchrotron light source ALBA is currently being commissioned along with the first phase of beamlines. Up to 6 beamlines are using light produced by Insertion Devices. There are up to four types of IDs: 2 Apple-II undulators (EU62 and EU71) operating at low energies, one conventional wiggler (MPW80) operating in the range of 2 – 20 keV, two in-vacuum undulators (IVU21) operating in the range 5 – 30 keV and a superconducting wiggler (SCW30) operating in the range of 40 keV. Installation of the IDs has been done in two steps. First, the out-vacuum devices (EU62, EU71 and MPW80) have been mechanically installed. Initial commissioning of Storage Ring has been done with their gaps opened to maximum value. Then, their gap has been closed to study the effect in the beam dynamics. In the second step, the in-vacuum devices (both IVU21 and the SCW30) have been installed and tested. In this paper we present the first results and performances of the insertion devices obtained both in Site Acceptance Test and during the first months of commissioning with beam.

THPO001

Design Power Supply Considerations to Compensate Booster Power Supply Effects on the SOLEIL Storage Ring

booster, power-supply, controls, dipole

3335

J.-P. Lavieville, R. Ben El Fekih, S. Bobault, D. Muller, L.S. Nadolski
SOLEIL, Gif-sur-Yvette, France

Top-up injection mode has been routinely in operation since March 2009 for various bunch filling patterns at Synchrotron SOLEIL. The electron beam stored current is maintained within 1%. At each injection the 3 Hz booster power supplies are ramped up and down over 10 seconds every 3 minutes in average. During this time DC and AC perturbations are observed on the storage ring horizontal closed orbit. Typically, the beamline source points can be shifted up to 10^-20 μm and the amplitude of the 3Hz frequency is multiplied by a factor 9. The origin of these perturbations lies in the imperfect compensation of the magnet currents circulating along the booster ring located inside the storage ring. To compensate these disturbances, a wire loop was installed in the booster cable tray fed by an in-house developed power supply. Its output current is driven by direct measurement of the main currents of the booster dipole, quadrupole, sextupole power supplies with a proper amplitude and phase shift. This paper presents the determination of the compensation needs according to beam measurements, the original design and the performance reached when this power supply is acting.

THPO007

Operation Status of SSRF Power Supplies and Interlocks for Top-up Operation

power-supply, controls, HOM, quadrupole

3349

R. Li, C.L. Guo, M.M. Huang, T.J. Shen
SINAP, Shanghai, People's Republic of China

Digital switching mode magnet power supplies are used in SSRF accelerators which have been operating since 2008. Summary of the operation and maintenance of these power supplies will be shared over here. The availability of the power supplies is increased steadily over the past 4 years. And the power supplies interlocks for the SSRF top-up operation will be also introduced in this paper.

THPO012

Using a High Precision Programmable DC Power Supply of TPS Magnet

power-supply, quadrupole, controls, sextupole

3358

Y.S. Wong, J.C. Huang, K.-B. Liu, W.S. Wen
NSRRC, Hsinchu, Taiwan

Taiwan government had been announcement to set up a third-generation synchrotron radiation light source in February 2010. It should be installed with 10³² sets of magnet power supplies for the storage ring and 152 sets for the injector. In the storage ring, high precision DC power supply for 48 dipoles magnets , 240 quadrupole magnets and 168 sextupole magnets. The main windings of quadrupole and sextupole magnets are powered by individual power supplies. In the booster rings, one set of dynamic power supply for the dipole magnets and four sets for quadrupole magnets run at the biased 3Hz quasi sinusoidal wave. The Taiwan photon source (TPS) plan was completed indication national synchrotron radiation research central (NSRRC) technical capability to build at its present site in seven years a 3~3.3 GeV electron energy, 518 meter circumference, low-emittance synchrotron storage ring which will offer one of the world's brightest synchrotron x-ray sources, provide cutting-edge experimental facilities and novel multidisciplinary scientific research opportunities, enhance world-class academic research, as well as create Taiwan's scientific research marvels in the twenty-first century.

THPO013

Development of a DSP-based Digital Control Three Phase Shunt Active Power Filter for Magnet Power Supply System

controls, power-supply, simulation, sextupole

3361

B.S. Wang, K.-B. Liu, Y.S. Wong
NSRRC, Hsinchu, Taiwan

There will be 240 quadruple and 168 sextuple magnet power supplies installed in TPS storage ring, power factor of these power supplies is an important issue to be concerned. A digital control three-phase shunt active power filter (APF) for quadruple and sextuple magnet power supplies is implemented and the power factor is better than 0.98. The APF power stage employs a three-phase switch-mode rectifier (SMR) to reduce the input current harmonics distortion and correct the power factor. The digital control circuit of the three-phase shunt active power filter is implemented by using a multi-channel 12 bits analog-to-digital converter、high resolution Pulse Width Modulated (PWM) and a TMS320F28335 digital signal processor (DSP). The system configuration is described in three function blocks include principle of compensation、design of the snubber protective circuit and control strategies. Finally, the feasibility and validity of proposed scheme is simulated with Matlab simulink and verified by the homemade digital control three-phase shunt active power filter.

THPO017

Improvement of Output Current Characteristics for Bira MCOR30 Correction Magnet Power Supply

controls, power-supply, HOM, feedback

3373

J.C. Huang, K.-B. Liu, Y.S. Wong
NSRRC, Hsinchu, Taiwan

The correction magnet power supplies installed at the Taiwan light source (TLS) are Bira Systems’ MCRO 30 power modules, a full-bridge configuration power stage converting the unregulated DC bulk power into a bi-polar current source. The MCOR 30 is theoretically regulated under a very fine control method, with this control method the Bira MCOR 30 should overcome the zero crossover distortion of a standard H-Bridge PWM schemes is used and result in a low frequency noise signature on the output when the magnet current is close to zero. The PWM control circuitry embedded in MCOR 30 theoretically but not really fulfills the purpose what the MCOR 30 want to achieve. With a home-made PWM control circuitry installed into MCOR 30, the width of real pulses can smoothly drop to zero, the MCOR 30 could output current not only with a low frequency noise signature but also much with higher bandwidth of frequency response and much lower Total Harmonic Distortion no matter what output current is demanded.

THPO018

N+1 Redundancy Power Supply System by Paralleling Current Converter Modules with Digital Regulation Control

controls, power-supply, feedback, simulation

3376

B.S. Wang, K.-B. Liu, Y.S. Wong
NSRRC, Hsinchu, Taiwan

The N+1 redundancy power supply system is fulfilled with adopting the Bira System MCOR30s as a platform, eight pieces of Bira MCOR 30 power converter boards are installed at crate 2512 and outputs are connected together, the output current of these paralleled eight Bira MCOR 30 power converters are regulated by an external homemade digital control circuit. With homemade digital control circuit, these paralleled eight Bira MCOR 30 power converter modules could deliver up to 240A/30V with ±20ppm precision and stability. The digital regulation control circuit of the N+1 redundancy power supply system is implemented by using a multi-channel DAC5868 16-bits digital-to-analog converter (DAC)、a high speed AD8382 18-bits analog-to-digital converter and a TMS320F28335 digital signal processor (DSP). The update reference voltage frequency of DAC is 83.3 kHz. A DCCT is used as the current feedback component and the output current ripple of the N+1 redundancy power supply system is lower than 20ppm which is beyond the requirement of current TLS quadruple and sextuple power supplies and qualified to be used in the future TPS facility.

THPO024

Development of a Non-Linear Kicker System to Facilitate a New Injection Scheme for the BESSY II Storage Ring

kicker, injection, vacuum, impedance

3394

O. Dressler, T. Atkinson, M. Dirsat, P. Kuske
HZB, Berlin, Germany
H. Rast
DELTA, Dortmund, Germany

Top-Up injections without noticeable motion of the stored beam is a challenge. The common method of beam accumulation with a local bump formed by four independent pulsed dipole kicker magnets usually causes beam oscillations. The matching of the four independent kicker systems regarding pulse jitters and shapes is technologically limited. Afterward the beam excitation was reduced more when two kicker magnets on each side of the septum were powered in series by one pulser unit. An even more promising approach is to adopt an alternative injection method deploying a single non-linear kicker magnet with zero Bx,y-field in the center and an off-axis maximum, By, which is horizontally displaced by 10^-12 mm. There the injected beam gets kicked and looses half of its transverse momentum. Such a magnet was designed and built as a short in-vacuum magnet with a small vertical gap height. For first beam tests the kicker was placed in the second straight section after the injection point, and the 1.5 μs pulse was designed to deflect the 1.72 GeV beam by 1 mrad. In this paper, the calculations of the magnetic fields, the mechanical design as well as the electrical pulser circuit are described.
*New injection scheme using a pulsed quadrupole magnet in electron storage rings, Kentaro Harada, PHYSICAL REVIEW SPECIAL TOPICS - AB 10, 123501 (2007)

THPZ011

Optimization of Chromatic Sextupoles in Electron Storage Rings Using Genetic Algorithms

sextupole, dynamic-aperture, resonance, emittance

3705

Z. Duan
IHEP Beijng, Beijing, People's Republic of China
Q. Qin
IHEP Beijing, Beijing, People's Republic of China

Funding: Work supported by National Science Foundation of China contract 10725525.
In order to suppress the head-tail instability, strong chromatic sextupoles are used in modern electron storage rings to correct large chromaticities due to small emittance or strong insertion quadrupoles to squeeze the bunch size at some places. However, the introduction of strong chromatic sextupoles also brings severe nonlinearity and might reduce dynamic aperture drastically. In the case of several sextupole families, the genetic algorithms are applied to find suitable configurations of sextupole strengths, directly maximizing dynamic aperture. A GeneRepair operator is introduced into the algorithm to correct chromaticities and optimize the dynamic aperture simultaneously in electron storage rings.

FRXAA01

Theory of Microwave Instability and Coherent Synchrotron Radiation in Electron Storage Rings

impedance, synchrotron, electron, shielding

3774

Y. Cai
SLAC, Menlo Park, California, USA

Funding: This work was supported by Department of Energy Contract No. DE-AC02-76SF00515.
Bursting of coherent synchrotron radiation has been observed and in fact used to generate THz radiation in many electron storage rings. In order to understand and control the bursting, we return to the study of the microwave instability. In this talk, we will report on the theoretical understanding, including recent developments, of the microwave instability in electron storage rings. The historical progress of the theories will be surveyed, starting from the dispersion relation of coasting beams, to the work of Sacherer on a bunched beam, and ending with the Oide and Yokoya method of discretization. This theoretical survey will be supplemented with key experimental results over the years. Finally, we will describe the recent theoretical development of utilizing the Laguerre polynomials in the presence of potential-well distortion. This self-consistent method will be applied to study the microwave instability driven by commonly known impedances, including that of coherent synchrotron radiation.

Slides FRXAA01 [0.948 MB]