IPAC2012 - List of Keywords (insertion)

Paper	Title	Other Keywords	Page
MOPPC007	Plans for High Beta Optics in the LHC	optics, quadrupole, emittance, scattering	133
	H. Burkhardt, A. Macpherson CERN, Geneva, Switzerland S. Cavalier, P.M. Puzo LAL, Orsay, France
	Based on what has been learned with the first high β^* = 90 m operation in 2011, we describe the potential and practical scenarios for reaching very high β^* in the LHC in 2012 and beyond. Very high β^* optics require dedicated running time and conditions in the LHC. We describe a plan which is optimized to maximize the physics potential in a minimum of dedicated running time.

MOPPC010	Parametric Study of Optics Options for the HL-LHC Project	optics, quadrupole, luminosity, sextupole	142
	R. De Maria CERN, Geneva, Switzerland
	Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, cofunded by the DoE, USA and KEK, Japan. The LHC Upgrade studies have been recently formalized into the High-Luminosity LHC (HL-LHC) project. The paper explores the parameter space in terms minimum beta star (flat and round), and luminosity leveling scenarios, constrained by the triplet gradient and aperture and still compatible with optics solutions based on the ATS scheme. The limitations of the proposed solutions, essentially given by the preservation of the dynamic aperture in the presence of large beta-beating waves induced in the arcs by the squeezing scheme are investigated. The results will be combined in scaling laws benchmarked with existing fully developed scenarios. S. Fartoukh et al., "The Achromatic Telescopic Squeezing (ATS) scheme: from initial motivations to basic principles, and first demonstration at the LHC," these proceedings.

MOPPC011	Optics and Layout Solutions for the HL-LHC with Large Aperture Nb3Sn and Nb-Ti Inner Triplets	optics, quadrupole, dynamic-aperture, injection	145
	S.D. Fartoukh, R. De Maria CERN, Geneva, Switzerland
	Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, co-funded by the DoE, USA and KEK, Japan. The LHC Upgrade studies, formalized into the High-Luminosity LHC (HL-LHC) project, relies on the feasibility of very low β^, and in particular on a novel achromatic squeezing mechanism, the ATS scheme which is presently under test in the LHC. We present two optics and layout scenario for the HL-LHC using the ATS scheme, one based on Nb3Sn triplet quadrupoles with a coil aperture compatible with an operational gradient of 150T/m and a backup scenario based on NbTi compatible with an operational gradient of 100T/m. The solution obtained are analyzed in terms of β^* reach (flat or round), mechanical acceptance, optics flexibility, chromatic properties, and impact on the dynamic aperture due to the large beta-beating waves induced in the arcs by the ATS scheme. * S. Fartoukh et al., "The Achromatic Telescopic Squeezing (ATS) scheme: from initial motivations to basic principles, and first demonstration at the LHC," these proceedings.

MOPPC013	Optics and Lattice Optimizations for the LHC Upgrade Project	optics, luminosity, lattice, ion	151
	B. Dalena CEA/IRFU, Gif-sur-Yvette, France R. Appleby UMAN, Manchester, United Kingdom A.V. Bogomyagkov BINP SB RAS, Novosibirsk, Russia A. Chancé, J. Payet CEA/DSM/IRFU, France R. De Maria, B.J. Holzer CERN, Geneva, Switzerland A. Faus-Golfe, J. Resta-López IFIC, Valencia, Spain K.M. Hock, M. Korostelev, L.N.S. Thompson, A. Wolski Cockcroft Institute, Warrington, Cheshire, United Kingdom C. Milardi INFN/LNF, Frascati (Roma), Italy
	The luminosity upgrade of the LHC collider at CERN is based on a strong focusing scheme to reach lowest values of the beta function at the collision points. Several issues have to be addressed in this context, that are considered as mid term goals for the optimisation of the lattice and beam optics: Firstly a number of beam optics have been developed to establish a baseline for the hardware R&D, and to define the specifications for the new magnets that will be needed, in Nb3Sn and in NbTi technology. Secondly, the need for sufficient flexibility of the beam optics especially for smallest β^* values has to be investigated as well as the need for a smooth transition between the injection and the collision optics. Finally the performance of the optics based on flat and round beams has to be compared and different ways have to be studied to optimise the chromatic correction, including the study of local correction schemes. This paper presents the status of this work, which is a result of an international collaboration, and summarises the main parameters that are foreseen to reach the HL-LHC luminosity goal.

MOPPC030	Status of the Decay Ring Design for the IDS Neutrino Factory	injection, kicker, lattice, optics	199
	D.J. Kelliher, C.R. Prior STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom N. Bliss, N.A. Collomb STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
	In the International Design Study for the Neutrino Factory (IDS-NF) a racetrack design has been adopted for the decay ring. The injection system into the decay ring is described. The feasibility of injecting both positive and negative muons into the ring is explored from the point of view of injection timing. Considerations for the design of a decay ring for a 10 GeV neutrino factory are included. ”International Design Study for the Neutrino Factory – interim design report”, RAL-TR-2011-018 (2011)

MOPPD074	Localization of Large Angle Foil Scattering Beam Loss Caused by Multi-Turn Charge-Exchange Injection	collimation, injection, simulation, scattering	535
	S. Kato Tohoku University, Graduate School of Science, Sendai, Japan H. Harada, S. Hatakeyama, J. Kamiya, M. Kinsho, K. Yamamoto, Y. Yamazaki, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	In the J-PARC RCS, the significant losses were observed at the branch of H⁰ dump line and the Beam Position Monitor which was put at the downstream of the H⁰ dump branch duct. These losses were caused by the large angle scattering of the injection and circulating beam at the charge exchange foil. To realize high power operation, we have to mitigate these losses. So, we started to develop a new collimation system in the H⁰ branch duct and installed in October 2011. In order to optimize this system efficiently, we primarily focused on the relative angle of collimator block from scattering particles. We simulated behavior of particles scattered by foil and produced by collimator block and researched most optimized position and angle of the collimator block. In this process, we devised the method of angular regulation of collimator block. We present the method of angular regulation and performance of this new collimation system.

MOPPP061	Using RADIA to Model Superconducting Wigglers at the Canadian Light Source	sextupole, wiggler, insertion-device, vacuum	699
	C.K. Baribeau, L.O. Dallin, M.J. Sigrist, W.A. Wurtz CLS, Saskatoon, Saskatchewan, Canada
	The Canadian Light Source operates two superconducting wigglers: a 2 Tesla, 63 pole wiggler, and a 4 Tesla, 27 pole wiggler. Both SCWs have a negative impact on the injection efficiency. Beam based measurements indicate a larger than expected sextupole moment, and the 4T wiggler produces a large horizontal tune shift. To better understand these effects, computer models were developed for the SCWs using the magnetic modelling software package, RADIA. The RADIA models accurately predict the wiggler on-axis field strength and vertical tune shift. By introducing physical misalignments, the models can produce sextupole moments of the same order of magnitude as the measured quantities. However, the modelled horizontal tune shift is orders of magnitude smaller than the 4T wiggler’s observed tune shift. Various model parameters were investigated for their effect on horizontal tune shift, but the cause of the 4T wiggler’s large horizontal tune shift remains unknown.

MOPPP067	In-vacuum, Cryogen-free Field Measurement System for Superconducting Undulator Coils	undulator, synchrotron, vacuum, insertion-device	714
	A.W. Grau, T. Baumbach, S. Casalbuoni, S. Gerstl, M. Hagelstein, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	The performance of superconducting insertion devices (IDs) depends strongly on the magnetic field quality. Before installing IDs in synchrotron light sources the characterization and precise measurements of their magnetic properties are of fundamental importance. Improvements in magnetic field measurement technology of conventional, i.e. permanent magnet based IDs, made significant progress during the last years and push the capabilities of synchrotron light sources. For superconducting IDs similar major developments are necessary. As a part of our R&D program for superconducting insertion devices we perform quality assessment of their magnetic field properties. This contribution describes details and challenges of the cryostat and measurement setup assembly to perform magnetic measurements of the local field and of the field integrals of superconducting undulator coils in a cold in-vacuum (cryogen free) environment. The focus will be on the outcome of the final acceptance test together with results of first tests performed with mock-up coils.

MOPPP069	First Measurements of COLDDIAG: A Cold Vacuum Chamber for Diagnostics	solenoid, electron, diagnostics, vacuum	720
	S. Gerstl, T. Baumbach, S. Casalbuoni, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany R. Bartolini, M.P. Cox, J.C. Schouten, R.P. Walker Diamond, Oxfordshire, United Kingdom M. Migliorati, B. Spataro INFN/LNF, Frascati (Roma), Italy I.R.R. Shinton UMAN, Manchester, United Kingdom
	Superconductive insertion devices can reach, for the same gap and period length, higher fields with respect to permanent magnet insertion devices. One of the still open issues for the development of superconductive insertion devices, is the understanding of the heat intake from the electron beam. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specifically for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, gas content as well as the flux of particles hitting the chamber walls. Here we report about the preliminary measurements and results of COLDDIAG installed in the Diamond storage ring.

MOPPP070	Characterization of Vacuum Chamber Samples for Superconducting Insertion Devices	vacuum, undulator, storage-ring, insertion-device	723
	D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, C. Heske, T. Holubek, B. Krause, A. Seiler, S. Stankov, L. Weinhardt Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany C.Z. Antoine, Y. Boudigou CEA/IRFU, Gif-sur-Yvette, France C. Boffo BNG, Würzburg, Germany
	One of the key components of a superconducting insertion device is the ultra-high vacuum (UHV) chamber. In order to reach the accelerator UHV specifications, it is very important to control the surface chemical content and find proper cleaning procedures. To keep the geometric and resistive wall losses small, it is essential that the top few μm of the surface exhibits low roughness and good electrical conductivity at low temperatures. A 300-μm-thick 316L stainless steel foil, galvanized with a 30-μm copper layer, is used for the next superconducting undulator developed in a collaboration between KIT and BNG. We report here on different spectroscopic analyses as well as on residual resistivity ratio RRR measurements of the copper surface after cleaning procedures and annealing at various temperatures for different periods of time.

MOPPP071	In Vacuum Conduction Cooled Superconducting Switch for Insertion Devices with Variable Period Length	vacuum, power-supply, insertion-device, FEL	726
	T. Holubek, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany C. Boffo, W. Walter BNG, Würzburg, Germany
	Switching the period length allows to increase the tunability of an insertion device. This can be realized in superconducting insertion devices (IDs) by reversing the current in a separately powered subsets of the superconducting windings. In order to use only one power supply instead of two for the two circuits, reducing the thermal input to the device, work is ongoing at ANKA to develop a superconducting switch. In this work we present the results of the test of an in-vacuum housed, conduction-cooled superconducting switch.

MOPPP079	Magnetic Tuning of the APS Wiggler as a Study for Tuning the NSLS-II Damping Wiggler	wiggler, multipole, damping, octupole	747
	I. Vasserman, M. Abliz, E. Gluskin, E. Trakhtenberg, J.Z. Xu ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357 A wide variety of tuning techniques has been developed and employed at Advanced Photon Source (APS) in the course of tuning insertion devices for use on the APS storage ring, the APS free electron laser, and in assisting with the LCLS undulator tuning. The tuning requirements for the National Synchrotron Source II (NSLS-II) damping wigglers are very demanding and include limits on the off-midplane field integrals that are new in the repertoire of undulator magnetic tuning. The goal of this study was to assess the applicability of existing tuning techniques to meeting the off-midplane requirements of NSLS-II. Tests were run using an available APS 8.5-cm-period wiggler. In addition to existing techniques, a special new shim design was tested. This report summarizes the results of these tests and shows that the wiggler can be tuned to the required specifications on the midplane over the requested ±15 mm in the horizontal direction. In the vertical direction, however, the specifications could only be met within ±0.5 mm. This falls short of the ±15 mm by ± 3 mm good-field region that is sought by NSLS-II.

MOPPP080	New Concepts for Revolver Undulator Designs	undulator, insertion-device, vacuum, controls	750
	B.K. Stillwell, J.H. Grimmer, D.P. Pasholk, E. Trakhtenberg ANL, Argonne, USA M.B. Patil Impact Engineering Solutions, Brookfield, USA
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Dynamic support of revolver undulator magnet structures presents a challenging mechanical problem. Some designs to date employ a support span connected at its ends to the undulator gap separation mechanism. However, this arrangement is problematic for long undulators operating at small gaps since the gap-dependent distortion of the magnet support span scales approximately with the cube of its length and exponentially with reduction in gap. Other designs have been demonstrated that utilize intermediate connections to a central magnet support span, but require additional stiffening members between that span and the magnet arrays. This arrangement is difficult to implement at the APS because of space constraints imposed by existing beam vacuum chambers. We have developed three revolver undulator concepts that provide an extremely rigid magnet support structure, precise rotational positioning, and wide gap tapering ability. Each of the concepts has advantages and disadvantages. All of the concepts are fully compatible with the existing APS-designed gap separation mechanism, which will greatly simplify testing and implementation.

MOPPP086	Praseodymium Iron-Boron Undulator With Textured Dysprosium Poles for Compact X-Ray FEL Applications	undulator, simulation, cryogenics, insertion-device	756
	R.B. Agustsson, Y.C. Chen, T.J. Grandsaert, A.Y. Murokh RadiaBeam, Santa Monica, USA F.H. O'Shea UCLA, Los Angeles, California, USA V. Solovyov BNL, Upton, Long Island, New York, USA
	Funding: DOE SBIR #97134S11-I Radiabeam Technologies is developing a novel ultra-high field short period undulator using two unconventional materials: praseodymium permanent magnets (PrFeB) and textured dysprosium (Tx Dy) ferromagnetic field concentrators. Both materials exhibit extraordinary magnetic properties at cryogenic temperatures, such as very large energy product and record high induction saturation, respectively. The proposed device combines PrFeB and Tx Dy in 3-D hybrid undulator geometry with sub-cm period and up to 3 Tesla pole tip field. Practical realization of these features will significantly surpass state-of-the-art and offer an ideal solution for the next generation of compact X-ray light sources. Initial simulations along with preliminary cryogenic measurements will be presented.

MOPPP088	Control of Nonlinear Dynamics by Active and Passive Methods for the NSLS-II Insertion Devices	undulator, polarization, insertion-device, electron	759
	J. Bengtsson, O.V. Chubar, C.A. Kitegi, T. Tanabe BNL, Upton, Long Island, New York, USA
	Funding: US DOE, Contract No. DE-AC02-98CH10886. Nonlinear dynamics effects from insertion devices (IDs) are known to affect the electron beam quality of third generation synchrotron light sources. In particular, beam lifetime, dynamical aperture and injection efficiency. Methods to model the IDs' non-linear effects are known, e.g. by second-order (in the inverse electron energy) kick maps. Methods to compensate these effects are known as well, e.g. by first-order thin or thick magnetic kicks introduced by "magic fingers," "L-shims," or "current strips." However, due to physical or technological constraints, these corrections are typically only partial. Therefore, a precise model is required for a correct minimization of the residual nonlinear dynamics effects for the combined magnetic fields of the ID and compensating magnets. We outline a systematic approach for such predictions, based on 3D magnetic field and local trajectory calculation in the ID by the Radia code, and particle tracking by Tracy-3. The optimal geometry for the compensating magnets is determined from these simulations using a combination of linear algebra and genetic optimization.

MOPPR084	Software Development for a CompactRIO-based Wire Scanner Control and Data Acquisition System	controls, EPICS, LabView, status	987
	J.D. Sedillo, J.D. Gilpatrick, D. Martinez, S. Rodriguez Esparza LANL, Los Alamos, New Mexico, USA M.E. Gruchalla URS, Albuquerque, New Mexico, USA
	Funding: U.S. Department of Energy The Beam Diagnostics and Instrumentation Team at the Los Alamos Neutron Science Center is developing a wire scanner data acquisition and control system with a National Instrument’s compactRIO at its core. For this application, the compactRIO controller not only requires programming the FPGA and RT computer internal to the compactRIO, but also requires programming a client computer and a touch panel display. This article will summarize the hardware interfaces and describe the software design approach utilized for programming and interfacing the four systems together in order to fulfill the design requirements and promote reliable interoperability.

TUOBB02	Commissioning of the PLS-II	insertion-device, storage-ring, power-supply, lattice	1089
	S. Shin, J.Y. Choi, T. Ha, J.Y. Huang, I. Hwang, W.H. Hwang, Y.D. Joo, C. Kim, D.T. Kim, D.E. Kim, J.M. Kim, M. Kim, S.H. Kim, S.-C. Kim, S.J. Kwon, B.-J. Lee, E.H. Lee, H.-S. Lee, H.M. Lee, J.W. Lee, S.H. Nam, E.S. Park, I.S. Park, S.S. Park, S.J. Park, Y.G. Son, J.C. Yoon PAL, Pohang, Kyungbuk, Republic of Korea J-Y. Kim, B.H. Oh KAERI, Daejon, Republic of Korea J. Lee POSTECH, Pohang, Kyungbuk, Republic of Korea
	The Pohang Light Source (PLS) has operated for 14 years successfully. To meet the request of the increasing user community, the PLS-II that is the upgrade project of PLS has been completed. Main goals of the PLS-II are to increase beam energy to 3 GeV, to increase number of insertion devices by the factor of two (20 IDs), to increase beam current to 400 mA and to reduce beam emittance below 10 nm with existing PLS tunnel and injection system. The PLS-II had been commissioned over the six months. During commissioning, we achieved 14 insertion devices operation and top-up operation with 100 mA beam current and 5.8 nm beam emittance. In this presentation, we report the experimental results from the PLS-II commissioning.
	Slides TUOBB02 [3.484 MB]

TUEPPB003	Nonlinear Accelerator with Transverse Motion Integrable in Normalized Polar Coordinates	lattice, simulation, focusing, damping	1116
	T.V. Zolkin University of Chicago, Chicago, Illinois, USA Y. Kharkov, I.A. Morozov BINP SB RAS, Novosibirsk, Russia S. Nagaitsev Fermilab, Batavia, USA
	Several families of nonlinear accelerator lattices with integrable transverse motion were suggested recently. One of the requirements for the existence of two analytic invariants is a special longitudinal coordinate dependence of fields. This paper presents the particle motion analysis when a problem becomes integrable in the normalized polar coordinates. This case is distinguished from the others: it yields an exact analytical solution and has a uniform longitudinal coordinate dependence of the fields (since the corresponding nonlinear potential is invariant under the transformation from the Cartesian to the normalized coordinates). A number of interesting features are revealed: while the frequency of radial oscillations is independent of the amplitude, the spread of angular frequencies in a beam is absolute. A corresponding spread of frequencies of oscillations in the Cartesian coordinates is evaluated via the simulation of transverse Schottky noise. V. Danilov and S. Nagaitsev, Phys. Rev. ST Accel. Beams 13 084002 (2010).*

TUEPPB009	First Measurements of the FACET Coherent Terahertz Radiation Source	radiation, electron, diagnostics, photon	1134
	Z. Wu, E. Adli, A.S. Fisher, M.J. Hogan, H. Loos SLAC, Menlo Park, California, USA
	Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515. The Facility for Accelerator science and Experimental Tests (FACET) at SLAC provides a high peak current, sub-ps bunched beam that is ideal for THz photon generation via coherent transition radiation. This paper presents preliminary characterization of the THz pulses generated by FACET electron beam. A one-micron thick Ti foil has been inserted into the beam path and the radiated photons collected. Michelson spectroscopy yields frequency content spanning from 0.25 THz to 2.3 THz and peaked at around 0.5 THz. Multiple scans at different bunch compression show a monotonic increase of the peak radiation frequency as the electron bunch gets shorter. Using the Kramers-Kronig relation, the temporal profile of the THz pulse is reconstructed from the power spectrum indicating a ~4 picosecond main pulse followed by a long oscillating tail due to the water absorption lines and detector response. Knife-edge scans measure a 4.4 mm x 4.8 mm transverse spot size at the focal point of the THz optical path. The total collected energy per pulse is 0.69 mJ measured by a Joulemeter. Fitting this total energy to the spatiotemporal profile of the THz pulse yields peak e-field amplitude of 1.5 MV/cm.

TUPPC025	Solaris Storage Ring Lattice Optimization with Strong Insertion Devices	lattice, optics, undulator, storage-ring	1218
	A.I. Wawrzyniak, C.J. Bocchetta Solaris, Kraków, Poland M. Eriksson, S.C. Leemann MAX-lab, Lund, Sweden
	Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09 The Solaris synchrotron light facility under construction in Kraków will be a replica of the 1.5 GeV storage ring of MAX IV. This compact 3rd generation light source has been designed to have an emittance of 6 nmrad and operate with 500 mA stored current for VUV and soft X-Rays production. The lattice design consists of 12 Double Bend Achromats (DBA) with each DBA cell integrated into one solid iron block. Twelve 3.5 m long straight sections are available of which 10 will be equipped in various insertion devices. These devices will differ from those adopted by MAX IV. For X-ray production one or more superconducting wigglers will be used, while APPLE II type undulators will be used for variable polarised light production. The linear and nonlinear lattice dynamics have been studied with these perturbing insertion devices included in the ring and results are presented in this paper.

TUPPC037	Update on LHeC Ring-Ring Optics	sextupole, optics, lattice, resonance	1242
	M. Fitterer KIT, Karlsruhe, Germany O.S. Brüning, H. Burkhardt, B.J. Holzer, J.M. Jowett CERN, Geneva, Switzerland M. Klein The University of Liverpool, Liverpool, United Kingdom
	An update of the LHeC Ring-Ring optics is presented which accounts for chromatic corrections and more flexibility in the tune adjustment.

TUPPC061	Commissioning of a beta∗ Knob for Dynamic IR Correction at RHIC	optics, luminosity, quadrupole, feedback	1314
	G. Robert-Demolaize, A. Marusic, S. Tepikian, S.M. White BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In addition to the recent optics correction technique demonstrated at CERN and applied at RHIC, it is important to have a separate tool to control the value of the beta functions at the collision point (beta∗). This becomes even more relevant when trying to reach high level of integrated luminosity while dealing with emittance blow-up over the length of a store, or taking advantage of compensation processes like stochastic cooling. Algorithms have been developed to allow modifying independently the beta function in each plane for each beam without significant increase in beam losses. The following reviews the principle of such algorithms and their experimental implementation as a dynamic beta-squeeze procedure.

TUPPP014	HiSOR-II, Compact Light Source with a Torus-knot Type Accumulator Ring	lattice, emittance, quadrupole, insertion-device	1635
	A. Miyamoto, S. Sasaki HSRC, Higashi-Hiroshima, Japan
	Funding: This work is partially supported by Cooperative and Supporting Program for Researches and Educations in University sponsored by KEK. We proposed a torus knot type synchrotron radiation ring where the beam orbit is not closed with one turn but return to the starting position after multiple turns around the ring. This ring is capable of having many straight sections and it is advantageous for installation of insertion devices. We named this architecture AMATELAS. We are designing a new ring based on the shape of a (11, 3) torus knot for our future plan HiSOR-II. This ring has eleven 3.6-m-long straight sections though the ring diameter is as compact as 15 m. The achieved emittance is 17.4 nmrad with the lattice having bending magnets with combined function. This level of emittance is as low as the conventional 3rd generation light source. On the other hand, there is a potential problem caused by that the radius of the orbit and focusing force are not constant in the bending magnets. However, we confirmed that it does not make serious influence to the beam by calculating with dividing the bending into several sections. We will compare the parameters of this new ring with the conventional ring which we have designed as the future plan of our facility and evaluate performance as the compact synchrotron light source.

TUPPP021	Orbit Stability at ALBA	insertion-device, wiggler, booster, undulator	1653
	M. Muñoz, G. Benedetti, D. Einfeld, J. Marcos, Z. Martí CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The synchrotron light source ALBA is in the final stage of the Storage Ring commissioning, with the beamline commissioning well under way. In the month of beam line commissioning, the storage ring has provided an stable beam, with horizontal and vertical stabilities better than the micrometer in both planes in DC and a good reproducibility of the beam position day by day. In this paper we review the performance of the Slow Orbit Feedback, the changes in orbit due to insertion devices, as well as the first measurement using the 10 kHz sampling mode of the Libera BPMs, together with the status of the implementation of the Fast Orbit Feedback system.

TUPPP028	A Study of Girder Alignment with Survey Measurements In the Diamond Storage Ring	survey, storage-ring, closed-orbit, sextupole	1674
	M. Apollonio, R. Bartolini, R.T. Fielder, W.J. Hoffman, J. Kay, I.P.S. Martin, B. Singh Diamond, Oxfordshire, United Kingdom
	Using a model of the Diamond storage ring which includes displacements and rotations of the 74 magnet girders an attempt has been made to correlate survey data with the corrector magnet (CM) strengths required for a zero orbit. We then use the model to deduce the most effective girder movements that will bring about a reduction in corrector strength. We describe the results of these studies, and suggest a test with a deliberately displaced girder and the effect on corrector strengths, aimed at enhancing our understanding of the system

TUPPP037	Status of the ALS Brightness Upgrade	lattice, brightness, emittance, insertion-device	1692
	C. Steier, B.J. Bailey, A. Biocca, A.T. Black, D. Colomb, N. Li, A. Madur, S. Marks, H. Nishimura, G.C. Pappas, S. Prestemon, D. Robin, S.L. Rossi, T. Scarvie, D. Schlueter, C. Sun, W. Wan LBNL, Berkeley, California, USA
	Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The Advanced Light Source (ALS) at Berkeley Lab while one of the earliest 3rd generation light sources remains one of the brightest sources for sof x-rays. Another multiyear upgrade of the ALS is currently under way, which includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade, which will reduce the horizontal emittance from 6.3 to 2.2 nm (2.6 nm effective). This will result in a brightness increase by a factor of three for bendmagnet beamlines and at least a factor of two for insertion device beamlines. Magnets for this upgrade are currently under production and will be installed later this year.

TUPPR068	The Achromatic Telescopic Squeezing Scheme: Basic Principles and First Demonstration at the LHC	optics, sextupole, injection, quadrupole	1978
	S.D. Fartoukh, R. De Maria, B. Goddard, W. Höfle, M. Lamont, G.J. Müller, L. Ponce, S. Redaelli, R.J. Steinhagen, M. Strzelczyk, R. Tomás, G. Vanbavinckhove, J. Wenninger CERN, Geneva, Switzerland R. Miyamoto ESS, Lund, Sweden
	The Achromatic Telescopic Squeezing (ATS) scheme [1] is a novel squeezing mechanism enabling the production of very low β^* in circular colliders. The basic principles of the ATS scheme will be reviewed together with its strong justification for the High-Luminosity LHC Project. In this context, a few dedicated beam experiments were meticulously prepared and took place at the LHC in 2011. The results obtained will be highlighted, demonstrating already the potential of the ATS scheme for any upgrade project relying on a strong reduction of β^. [1] S. Fartoukh, "An Achromatic Telescopic Squeezing (ATS) Scheme For The LHC Upgrade," IPAC'11, WEPC037, p. 2088 (2001).*

WEPPC017	Design of a High-Speed Pulsed 324MHz Solid-State Amplifier for Use in a Beam Chopper	resonance, impedance, proton, feedback	2242
	S.C. Dillon, B.S. Nobel, C.P. Schach Tomco Technologies, Stepney, South Australia, Australia
	A 324MHz 30kW high-speed pulsed solid-state amplifier has been designed for use in a beam chopper at the Japan Proton Accelerator Complex (J-PARC). This paper discusses the various design challenges and presents the initial performance test results. In particular, the amplifier achieves pulse rise and fall times of less than 15 nanoseconds, is easily upgradeable in power, and withstands 100% power reflection without damage.

WEPPD010	Re-commissioning of the ESRF Storage Ring Vacuum System	vacuum, storage-ring, synchrotron, insertion-device	2516
	M. Hahn, I. Parat ESRF, Grenoble, France
	A long shutdown of the accelerators to allow the construction of new buildings marked the phase one of the ESRF upgrade program. A number of vacuum sectors has been modified during this time for repair and maintenance but mainly to increase the brilliance of the synchrotron radiation beams by installing longer insertion device (ID) vessels with non-evaporable getter (NEG) coating and a new In Vacuum Undulator. The paper gives an overview of the modified machine and reports experience with its re-conditioning.

WEPPD015	Saturation Behaviour of the LHC NEG Coated Beam Pipes	vacuum, simulation, injection, site	2525
	G. Bregliozzi, V. Baglin, J.M. Jimenez, G. Lanza, T. Porcelli CERN, Geneva, Switzerland
	In the CERN Large Hadron Collider (LHC), about 6 km of the UHV beam pipe are at room temperature and serve as experimental or utility insertions. TiZrV non-evaporable getter (NEG) coating is used to maintain the design pressure during beam operation. Molecular desorption due to dynamic effects is stimulated during protons operation at high intensity. This phenomenon produces an important gas load from the vacuum chamber walls which could lead to a partial or total saturation of the NEG coating. To keep the design vacuum performances and to schedule technical interventions for NEG re-activation, it is necessary to take in account all these aspects and to regularly evaluate the saturation level of the NEG coating. Experimental studies in a typical LHC vacuum sector were conducted in order to identify the best method to assess the saturation level of the beam pipe. Partial saturation of the NEG was performed and the effects in the variations of pressure reading, effective pumping speed, transmission and capture probability are analysed. Finally, based on these results, a detailed analysis of the NEG coating saturation level of some area of the LHC is presented and analysed.

WEPPD042	The Grounding System at TPS	site, synchrotron, emittance, controls	2606
	T.-S. Ueng, J.-C. Chang, J.-R. Chen, Y.-C. Lin NSRRC, Hsinchu, Taiwan
	An elaborately designed grounding system has been installed under the TPS construction site. The ground grid was installed sector by sector to comply with the building construction schedule. The ground resistance measurement of each sector was carried out right after the grid installation. The final ground resistance measurement for the whole grounding system was performed also right after its completion. The measured ground resistances of each sector were used to estimate the final TPS ground resistance, and it was compared to the final TPS ground measurement result. Also, the analysis with computer software is used to justify it. The low impedance of TPS grounding system, < 0.15 ohm, is to insure the safety of TPS personnel and instrumentation, also, to reduce the noise of electronic devices.

WEPPD071	The FLUKA LineBuilder and Element DataBase: Tools for Building Complex Models of Accelerator Beam Lines	optics, simulation, injection, proton	2687
	A. Mereghetti UMAN, Manchester, United Kingdom V. Boccone, F. Cerutti, R. Versaci, V. Vlachoudis CERN, Geneva, Switzerland
	Extended FLUKA models of accelerator beam lines can be extremely complex: heavy to manipulate, poorly versatile and prone to mismatched positioning. We developed a framework capable of creating the FLUKA model of an arbitrary portion of a given accelerator, starting from the optics configuration and a few other information provided by the user. The framework includes a builder (LineBuilder), an element database and a series of configuration and analysis scripts. The LineBuilder is a Python program aimed at dynamically assembling complex FLUKA models of accelerator beam lines: positions, magnetic fields and scorings are automatically set up, and geometry details such as apertures of collimators, tilting and misalignment of elements, beam pipes and tunnel geometries can be entered at user's will. The element database (FEDB) is a collection of detailed FLUKA geometry models of machine elements. This framework has been widely used for recent LHC and SPS beam-machine interaction studies at CERN, and led to a drastic reduction in the time otherwise required to rework old machine models, and to a coherent and traceable description of the inputs used for all the simulations.

WEPPP065	Status of the SSRF Fast Orbit Feedback System	feedback, controls, storage-ring, electron	2855
	B.C. Jiang, J. Hou, C.X. Yin, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	The fast orbit feedback system with bandwidth up to 100Hz is under commissioning at SSRF. The main purposes of the system are to suppress the short term orbit stability under sub-micron level and to compensate the orbit distortions caused by changing gaps of the insertion devices. The layout of the system is described and the preliminary commissioning results are given out in this paper.

WEPPP087	The Improvement and Test of Laser Positioning System for TPS Magnets Alignment Inspection	laser, quadrupole, alignment, sextupole	2915
	M.L. Chen, J.-R. Chen, H.C. Ho, K.H. Hsu, W.Y. Lai, C.-S. Lin, C.J. Lin, H.C. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan
	A Laser positioning system, consist of a laser, laser position sensing devices (PSD) module and two granite blocks, is developed for the alignment inspection of TPS (Taiwan Photon Source) quadrupole and sextupole magnets during installation on a girder. The PSD module is adapted on the pole center of magnet and is designed to stand for mechanical center of magnets. For high accuracy, eliminating the influence of magnets manufacturing errors between PSD module is a major work. The PSD is mounted on a precise diameter expansible jig to absorb the manufacturing errors. The real roundness of the expansible jig can keep under 3um when diameter is expanded 80um. The PSD position is adjusted and corrected in advance, and then the PSD module center can be identical to the ideal pole position of magnets on the girder within 15um. The magnet will be aligned and adjusted by laser position on PSD. This paper describes how to eliminate the measuring error caused by magnet manufacturing error and the detail of alignment inspection procedure of magnets during the installation on a girder.

THPPC009	Investigation of the Approaches to Measure the RF Cable Attenuation	controls, linac, acceleration, radio-frequency	3290
	K. Futatsukawa, Z. Fang, Y. Fukui, T. Kobayashi, S. Michizono KEK, Ibaraki, Japan F. Sato, S. Shinozaki JAEA/J-PARC, Tokai-mura, Japan
	In the accelerator facilities, many RF cables are used for the various purposes such as the transmission system and the cavity monitor. The knowledge of the power attenuation in those cables is important role to control RF. In general, the cable attenuation is measured from S parameters to use a network analyzer. However, the control system is located far from the place of the cavities, and it difficult to measure by a network analyzer. Then we investigated other methods to measure the RF cable attenuation.

THPPC073	Development of the Energy-Efficient Solid State RF Power Source for the Jefferson Laboratory CEBAF Linac	controls, klystron, linac, high-voltage	3455
	X. Chang, N. Barov, D.J. Newsham, D. Wu Far-Tech, Inc., San Diego, California, USA
	Funding: Work supported by DOE Office of Nuclear Physics, DOE-SBIR #DE-SC0002529 We present the current status of FAR-TECH's Solid State RF Power Source for the Jefferson Laboratory CEBAF Linac. This power source design features up to 8 kW CW RF output power, GaN amplifier stages with high efficiency (>60%), and a compact design to fit existing rack space and cooling requirements at the installation site. We have finished most of the designs and have performed successfully the most critical tests of this project, the 4 to 1 combiner test and the cooling test. FAR-TECH’s solid state amplifier design has high efficiency, a wide range of design frequency (DC-3GHz), and long lifetime, which provides a good RF power source.

THPPD030	Characterization of a Measurement System for Dynamic Effects in Large-aperture SC Quadrupole Magnets	quadrupole, multipole, superconducting-magnet, controls	3569
	S. Russenschuck, M. Bajko, M.C.L. Buzio, G. Deferne, O. Dunkel, L. Fiscarelli, D. Giloteaux, L. Walckiers CERN, Geneva, Switzerland
	A new measurement system, based on a large-diameter search-coil rotating in the superfluid helium, a fast digital integrator, a motor drive unit with sliprings, and a flexible software environment was devolped at CERN for the measurement of dynamic effects in superconducting magnets. This system has made it possible the measure, with a resolution of up to 8 Hz, the multipole field errors due to superconductor magnetization and interstrand coupling currents. In the paper we will present the development and calibration of the measurement system, its installation in the vertical cryostat of CERN's recently refurbished test station, and its application to the US-LARP* built, 120-mm-aperture Nb3Sn quadrupole magnet (HQ) for the upgrade of the LHC insertion regions. * P. Arpaia et al. Active Comp. of Field Errors within ± 2 PPM in SC Magnets, NIM A, 2011 ** H. Felice et al. Design of HQ, a High Field Large Bore Nb3Sn Quad. Magnet for LARP, IEEE TAS, 2009

THPPD059	Conductive EMI Reduction to Kicker Magnet Power Supply in NSRRC	kicker, power-supply, controls, synchrotron	3647
	Y.-H. Liu, J.-C. Chang, C.S. Chen, H.H. Chen, J.-R. Chen NSRRC, Hsinchu, Taiwan
	The purpose of this paper is to estimate and reduce the conductive Electromagnetic Interference (EMI) from kicker magnet power supply in TLS. A LISN system was conducted to measure the EMI spectrum of kicker power supply. The EMI noise exceeded FCC standards in some frequency range especially during kicker firing. Reducing EMI level by using different EMI filters were applied. Double pi filter was more efficient than single pi filter. After using filter, the conducted EMI could diminish lower than FCC class B. The experimental results will provide useful information to future TPS pulsed magnet design.

THPPP038	Simulations of the Influence of 4-Rod RFQ Elements on its Voltage Distribution	rfq, simulation, resonance, linac	3818
	J.S. Schmidt, B. Koubek, A. Schempp IAP, Frankfurt am Main, Germany
	The influence of tuning methods and other design elements of 4-rod-RFQs on the voltage distribution have been studied during the last months. Every change in the field geometry or the voltage distribution could for example lead to particle losses or a raise in the surface current on single parts of the RFQ. That’s why further research had to be done about the behavior of the 4-rod-RFQ especially in the comparison of structures at 100 or 200 MHz. The results of an analysis which is concentrated on simulations using CST Microwave Studio to evaluate the effects of the overhang of electrodes, modulation and piston tuners on the fields in the RFQ are presented in this paper.

THPPR011	Insertion Device Controls Plan of the Taiwan Photon Source	controls, insertion-device, EPICS, vacuum	3987
	C.Y. Wu, J. Chen, Y.-S. Cheng, K.T. Hsu, S.Y. Hsu, K.H. Hu, C.H. Kuo, D. Lee, C.Y. Liao NSRRC, Hsinchu, Taiwan
	Insertion device (ID) is a crucial component in third-generation synchrotron light sources, which can produces highly-brilliant, forward-directed and quasi-monochromatic radiation over a broad energy range for various experiments. In the phase I of the Taiwan Photon Source (TPS) project, ten insertion devices (IDs) will be planned, constructed, and installed for the first seven beamlines. The control system for all the IDs is based on the EPICS architecture. The main control components include the motor with encoder for gap adjustment, trim coil power supply for corrector magnets, temperature sensor for ID environmental monitoring and baking (only for In-Vacuum Undulator), and interlock system (limit switches, tilt sensor) for safety. The progress of the controls plan will be summarized in this report.

THPPR036	Quench Limit Calculations for Steady State Heat Deposits in LHC Inner Triplet Magnets	quadrupole, proton, luminosity, simulation	4050
	D. Bocian IFJ-PAN, Kraków, Poland F. Cerutti, B. Dehning, A.P. Siemko CERN, Geneva, Switzerland
	In hadron colliders such as the LHC, the energy deposited in the superconductors by the particles lost from the beams or coming from the collision debris may provoke quenches detrimental to the accelerator operation. A Network Model is used to simulate the thermodynamic behavior of the superconducting magnets. In previous papers the validations of network model with measurements performed in the CERN and Fermilab magnet test facilities were presented. This model was subsequently used for thermal analysis of the current LHC inner triplet quadrupole magnets for beam energy of 3.5 TeV and 7 TeV. The detailed study of helium cooling channels efficiency for energy deposits simulated with FLUKA is presented. Some conclusions are drawn on expected inner triplet magnets quench limit.

Paper

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Other Keywords

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MOPPC007

Plans for High Beta Optics in the LHC

optics, quadrupole, emittance, scattering

133

H. Burkhardt, A. Macpherson
CERN, Geneva, Switzerland
S. Cavalier, P.M. Puzo
LAL, Orsay, France

Based on what has been learned with the first high β^* = 90 m operation in 2011, we describe the potential and practical scenarios for reaching very high β^* in the LHC in 2012 and beyond. Very high β^* optics require dedicated running time and conditions in the LHC. We describe a plan which is optimized to maximize the physics potential in a minimum of dedicated running time.

MOPPC010

Parametric Study of Optics Options for the HL-LHC Project

optics, quadrupole, luminosity, sextupole

142

R. De Maria
CERN, Geneva, Switzerland

Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, cofunded by the DoE, USA and KEK, Japan.
The LHC Upgrade studies have been recently formalized into the High-Luminosity LHC (HL-LHC) project. The paper explores the parameter space in terms minimum beta star (flat and round), and luminosity leveling scenarios, constrained by the triplet gradient and aperture and still compatible with optics solutions based on the ATS scheme*. The limitations of the proposed solutions, essentially given by the preservation of the dynamic aperture in the presence of large beta-beating waves induced in the arcs by the squeezing scheme are investigated. The results will be combined in scaling laws benchmarked with existing fully developed scenarios.
* S. Fartoukh et al., "The Achromatic Telescopic Squeezing (ATS) scheme: from initial motivations to basic principles, and first demonstration at the LHC," these proceedings.

MOPPC011

Optics and Layout Solutions for the HL-LHC with Large Aperture Nb3Sn and Nb-Ti Inner Triplets

optics, quadrupole, dynamic-aperture, injection

145

S.D. Fartoukh, R. De Maria
CERN, Geneva, Switzerland

Funding: The research leading to these results has received funding from the European Commission under the FP7 project HiLumi LHC, GA no. 284404, co-funded by the DoE, USA and KEK, Japan.
The LHC Upgrade studies, formalized into the High-Luminosity LHC (HL-LHC) project, relies on the feasibility of very low β^*, and in particular on a novel achromatic squeezing mechanism, the ATS scheme which is presently under test in the LHC*. We present two optics and layout scenario for the HL-LHC using the ATS scheme, one based on Nb3Sn triplet quadrupoles with a coil aperture compatible with an operational gradient of 150T/m and a backup scenario based on NbTi compatible with an operational gradient of 100T/m. The solution obtained are analyzed in terms of β^* reach (flat or round), mechanical acceptance, optics flexibility, chromatic properties, and impact on the dynamic aperture due to the large beta-beating waves induced in the arcs by the ATS scheme.
* S. Fartoukh et al., "The Achromatic Telescopic Squeezing (ATS) scheme: from initial motivations to basic principles, and first demonstration at the LHC," these proceedings.

MOPPC013

Optics and Lattice Optimizations for the LHC Upgrade Project

optics, luminosity, lattice, ion

151

B. Dalena
CEA/IRFU, Gif-sur-Yvette, France
R. Appleby
UMAN, Manchester, United Kingdom
A.V. Bogomyagkov
BINP SB RAS, Novosibirsk, Russia
A. Chancé, J. Payet
CEA/DSM/IRFU, France
R. De Maria, B.J. Holzer
CERN, Geneva, Switzerland
A. Faus-Golfe, J. Resta-López
IFIC, Valencia, Spain
K.M. Hock, M. Korostelev, L.N.S. Thompson, A. Wolski
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C. Milardi
INFN/LNF, Frascati (Roma), Italy

The luminosity upgrade of the LHC collider at CERN is based on a strong focusing scheme to reach lowest values of the beta function at the collision points. Several issues have to be addressed in this context, that are considered as mid term goals for the optimisation of the lattice and beam optics: Firstly a number of beam optics have been developed to establish a baseline for the hardware R&D, and to define the specifications for the new magnets that will be needed, in Nb3Sn and in NbTi technology. Secondly, the need for sufficient flexibility of the beam optics especially for smallest β^* values has to be investigated as well as the need for a smooth transition between the injection and the collision optics. Finally the performance of the optics based on flat and round beams has to be compared and different ways have to be studied to optimise the chromatic correction, including the study of local correction schemes. This paper presents the status of this work, which is a result of an international collaboration, and summarises the main parameters that are foreseen to reach the HL-LHC luminosity goal.

MOPPC030

Status of the Decay Ring Design for the IDS Neutrino Factory

injection, kicker, lattice, optics

199

D.J. Kelliher, C.R. Prior
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
N. Bliss, N.A. Collomb
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
J. Pasternak
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom

In the International Design Study for the Neutrino Factory (IDS-NF) a racetrack design has been adopted for the decay ring*. The injection system into the decay ring is described. The feasibility of injecting both positive and negative muons into the ring is explored from the point of view of injection timing. Considerations for the design of a decay ring for a 10 GeV neutrino factory are included.
* ”International Design Study for the Neutrino Factory – interim design report”, RAL-TR-2011-018 (2011)

MOPPD074

Localization of Large Angle Foil Scattering Beam Loss Caused by Multi-Turn Charge-Exchange Injection

collimation, injection, simulation, scattering

535

S. Kato
Tohoku University, Graduate School of Science, Sendai, Japan
H. Harada, S. Hatakeyama, J. Kamiya, M. Kinsho, K. Yamamoto, Y. Yamazaki, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

In the J-PARC RCS, the significant losses were observed at the branch of H⁰ dump line and the Beam Position Monitor which was put at the downstream of the H⁰ dump branch duct. These losses were caused by the large angle scattering of the injection and circulating beam at the charge exchange foil. To realize high power operation, we have to mitigate these losses. So, we started to develop a new collimation system in the H⁰ branch duct and installed in October 2011. In order to optimize this system efficiently, we primarily focused on the relative angle of collimator block from scattering particles. We simulated behavior of particles scattered by foil and produced by collimator block and researched most optimized position and angle of the collimator block. In this process, we devised the method of angular regulation of collimator block. We present the method of angular regulation and performance of this new collimation system.

MOPPP061

Using RADIA to Model Superconducting Wigglers at the Canadian Light Source

sextupole, wiggler, insertion-device, vacuum

699

C.K. Baribeau, L.O. Dallin, M.J. Sigrist, W.A. Wurtz
CLS, Saskatoon, Saskatchewan, Canada

The Canadian Light Source operates two superconducting wigglers: a 2 Tesla, 63 pole wiggler, and a 4 Tesla, 27 pole wiggler. Both SCWs have a negative impact on the injection efficiency. Beam based measurements indicate a larger than expected sextupole moment, and the 4T wiggler produces a large horizontal tune shift. To better understand these effects, computer models were developed for the SCWs using the magnetic modelling software package, RADIA. The RADIA models accurately predict the wiggler on-axis field strength and vertical tune shift. By introducing physical misalignments, the models can produce sextupole moments of the same order of magnitude as the measured quantities. However, the modelled horizontal tune shift is orders of magnitude smaller than the 4T wiggler’s observed tune shift. Various model parameters were investigated for their effect on horizontal tune shift, but the cause of the 4T wiggler’s large horizontal tune shift remains unknown.

MOPPP067

In-vacuum, Cryogen-free Field Measurement System for Superconducting Undulator Coils

undulator, synchrotron, vacuum, insertion-device

714

A.W. Grau, T. Baumbach, S. Casalbuoni, S. Gerstl, M. Hagelstein, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

The performance of superconducting insertion devices (IDs) depends strongly on the magnetic field quality. Before installing IDs in synchrotron light sources the characterization and precise measurements of their magnetic properties are of fundamental importance. Improvements in magnetic field measurement technology of conventional, i.e. permanent magnet based IDs, made significant progress during the last years and push the capabilities of synchrotron light sources. For superconducting IDs similar major developments are necessary. As a part of our R&D program for superconducting insertion devices we perform quality assessment of their magnetic field properties. This contribution describes details and challenges of the cryostat and measurement setup assembly to perform magnetic measurements of the local field and of the field integrals of superconducting undulator coils in a cold in-vacuum (cryogen free) environment. The focus will be on the outcome of the final acceptance test together with results of first tests performed with mock-up coils.

MOPPP069

First Measurements of COLDDIAG: A Cold Vacuum Chamber for Diagnostics

solenoid, electron, diagnostics, vacuum

720

S. Gerstl, T. Baumbach, S. Casalbuoni, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
R. Bartolini, M.P. Cox, J.C. Schouten, R.P. Walker
Diamond, Oxfordshire, United Kingdom
M. Migliorati, B. Spataro
INFN/LNF, Frascati (Roma), Italy
I.R.R. Shinton
UMAN, Manchester, United Kingdom

Superconductive insertion devices can reach, for the same gap and period length, higher fields with respect to permanent magnet insertion devices. One of the still open issues for the development of superconductive insertion devices, is the understanding of the heat intake from the electron beam. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specifically for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, gas content as well as the flux of particles hitting the chamber walls. Here we report about the preliminary measurements and results of COLDDIAG installed in the Diamond storage ring.

MOPPP070

Characterization of Vacuum Chamber Samples for Superconducting Insertion Devices

vacuum, undulator, storage-ring, insertion-device

723

D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, C. Heske, T. Holubek, B. Krause, A. Seiler, S. Stankov, L. Weinhardt
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
C.Z. Antoine, Y. Boudigou
CEA/IRFU, Gif-sur-Yvette, France
C. Boffo
BNG, Würzburg, Germany

One of the key components of a superconducting insertion device is the ultra-high vacuum (UHV) chamber. In order to reach the accelerator UHV specifications, it is very important to control the surface chemical content and find proper cleaning procedures. To keep the geometric and resistive wall losses small, it is essential that the top few μm of the surface exhibits low roughness and good electrical conductivity at low temperatures. A 300-μm-thick 316L stainless steel foil, galvanized with a 30-μm copper layer, is used for the next superconducting undulator developed in a collaboration between KIT and BNG. We report here on different spectroscopic analyses as well as on residual resistivity ratio RRR measurements of the copper surface after cleaning procedures and annealing at various temperatures for different periods of time.

MOPPP071

In Vacuum Conduction Cooled Superconducting Switch for Insertion Devices with Variable Period Length

vacuum, power-supply, insertion-device, FEL

726

T. Holubek, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
C. Boffo, W. Walter
BNG, Würzburg, Germany

Switching the period length allows to increase the tunability of an insertion device. This can be realized in superconducting insertion devices (IDs) by reversing the current in a separately powered subsets of the superconducting windings. In order to use only one power supply instead of two for the two circuits, reducing the thermal input to the device, work is ongoing at ANKA to develop a superconducting switch. In this work we present the results of the test of an in-vacuum housed, conduction-cooled superconducting switch.

MOPPP079

Magnetic Tuning of the APS Wiggler as a Study for Tuning the NSLS-II Damping Wiggler

wiggler, multipole, damping, octupole

747

I. Vasserman, M. Abliz, E. Gluskin, E. Trakhtenberg, J.Z. Xu
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357
A wide variety of tuning techniques has been developed and employed at Advanced Photon Source (APS) in the course of tuning insertion devices for use on the APS storage ring, the APS free electron laser, and in assisting with the LCLS undulator tuning. The tuning requirements for the National Synchrotron Source II (NSLS-II) damping wigglers are very demanding and include limits on the off-midplane field integrals that are new in the repertoire of undulator magnetic tuning. The goal of this study was to assess the applicability of existing tuning techniques to meeting the off-midplane requirements of NSLS-II. Tests were run using an available APS 8.5-cm-period wiggler. In addition to existing techniques, a special new shim design was tested. This report summarizes the results of these tests and shows that the wiggler can be tuned to the required specifications on the midplane over the requested ±15 mm in the horizontal direction. In the vertical direction, however, the specifications could only be met within ±0.5 mm. This falls short of the ±15 mm by ± 3 mm good-field region that is sought by NSLS-II.

MOPPP080

New Concepts for Revolver Undulator Designs

undulator, insertion-device, vacuum, controls

750

B.K. Stillwell, J.H. Grimmer, D.P. Pasholk, E. Trakhtenberg
ANL, Argonne, USA
M.B. Patil
Impact Engineering Solutions, Brookfield, USA

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Dynamic support of revolver undulator magnet structures presents a challenging mechanical problem. Some designs to date employ a support span connected at its ends to the undulator gap separation mechanism. However, this arrangement is problematic for long undulators operating at small gaps since the gap-dependent distortion of the magnet support span scales approximately with the cube of its length and exponentially with reduction in gap. Other designs have been demonstrated that utilize intermediate connections to a central magnet support span, but require additional stiffening members between that span and the magnet arrays. This arrangement is difficult to implement at the APS because of space constraints imposed by existing beam vacuum chambers. We have developed three revolver undulator concepts that provide an extremely rigid magnet support structure, precise rotational positioning, and wide gap tapering ability. Each of the concepts has advantages and disadvantages. All of the concepts are fully compatible with the existing APS-designed gap separation mechanism, which will greatly simplify testing and implementation.

MOPPP086

Praseodymium Iron-Boron Undulator With Textured Dysprosium Poles for Compact X-Ray FEL Applications

undulator, simulation, cryogenics, insertion-device

756

R.B. Agustsson, Y.C. Chen, T.J. Grandsaert, A.Y. Murokh
RadiaBeam, Santa Monica, USA
F.H. O'Shea
UCLA, Los Angeles, California, USA
V. Solovyov
BNL, Upton, Long Island, New York, USA

Funding: DOE SBIR #97134S11-I
Radiabeam Technologies is developing a novel ultra-high field short period undulator using two unconventional materials: praseodymium permanent magnets (PrFeB) and textured dysprosium (Tx Dy) ferromagnetic field concentrators. Both materials exhibit extraordinary magnetic properties at cryogenic temperatures, such as very large energy product and record high induction saturation, respectively. The proposed device combines PrFeB and Tx Dy in 3-D hybrid undulator geometry with sub-cm period and up to 3 Tesla pole tip field. Practical realization of these features will significantly surpass state-of-the-art and offer an ideal solution for the next generation of compact X-ray light sources. Initial simulations along with preliminary cryogenic measurements will be presented.

MOPPP088

Control of Nonlinear Dynamics by Active and Passive Methods for the NSLS-II Insertion Devices

undulator, polarization, insertion-device, electron

759

J. Bengtsson, O.V. Chubar, C.A. Kitegi, T. Tanabe
BNL, Upton, Long Island, New York, USA

Funding: US DOE, Contract No. DE-AC02-98CH10886.
Nonlinear dynamics effects from insertion devices (IDs) are known to affect the electron beam quality of third generation synchrotron light sources. In particular, beam lifetime, dynamical aperture and injection efficiency. Methods to model the IDs' non-linear effects are known, e.g. by second-order (in the inverse electron energy) kick maps. Methods to compensate these effects are known as well, e.g. by first-order thin or thick magnetic kicks introduced by "magic fingers," "L-shims," or "current strips." However, due to physical or technological constraints, these corrections are typically only partial. Therefore, a precise model is required for a correct minimization of the residual nonlinear dynamics effects for the combined magnetic fields of the ID and compensating magnets. We outline a systematic approach for such predictions, based on 3D magnetic field and local trajectory calculation in the ID by the Radia code, and particle tracking by Tracy-3. The optimal geometry for the compensating magnets is determined from these simulations using a combination of linear algebra and genetic optimization.

MOPPR084

Software Development for a CompactRIO-based Wire Scanner Control and Data Acquisition System

controls, EPICS, LabView, status

987

J.D. Sedillo, J.D. Gilpatrick, D. Martinez, S. Rodriguez Esparza
LANL, Los Alamos, New Mexico, USA
M.E. Gruchalla
URS, Albuquerque, New Mexico, USA

Funding: U.S. Department of Energy
The Beam Diagnostics and Instrumentation Team at the Los Alamos Neutron Science Center is developing a wire scanner data acquisition and control system with a National Instrument’s compactRIO at its core. For this application, the compactRIO controller not only requires programming the FPGA and RT computer internal to the compactRIO, but also requires programming a client computer and a touch panel display. This article will summarize the hardware interfaces and describe the software design approach utilized for programming and interfacing the four systems together in order to fulfill the design requirements and promote reliable interoperability.

TUOBB02

Commissioning of the PLS-II

insertion-device, storage-ring, power-supply, lattice

1089

S. Shin, J.Y. Choi, T. Ha, J.Y. Huang, I. Hwang, W.H. Hwang, Y.D. Joo, C. Kim, D.T. Kim, D.E. Kim, J.M. Kim, M. Kim, S.H. Kim, S.-C. Kim, S.J. Kwon, B.-J. Lee, E.H. Lee, H.-S. Lee, H.M. Lee, J.W. Lee, S.H. Nam, E.S. Park, I.S. Park, S.S. Park, S.J. Park, Y.G. Son, J.C. Yoon
PAL, Pohang, Kyungbuk, Republic of Korea
J-Y. Kim, B.H. Oh
KAERI, Daejon, Republic of Korea
J. Lee
POSTECH, Pohang, Kyungbuk, Republic of Korea

The Pohang Light Source (PLS) has operated for 14 years successfully. To meet the request of the increasing user community, the PLS-II that is the upgrade project of PLS has been completed. Main goals of the PLS-II are to increase beam energy to 3 GeV, to increase number of insertion devices by the factor of two (20 IDs), to increase beam current to 400 mA and to reduce beam emittance below 10 nm with existing PLS tunnel and injection system. The PLS-II had been commissioned over the six months. During commissioning, we achieved 14 insertion devices operation and top-up operation with 100 mA beam current and 5.8 nm beam emittance. In this presentation, we report the experimental results from the PLS-II commissioning.

Slides TUOBB02 [3.484 MB]

TUEPPB003

Nonlinear Accelerator with Transverse Motion Integrable in Normalized Polar Coordinates

lattice, simulation, focusing, damping

1116

T.V. Zolkin
University of Chicago, Chicago, Illinois, USA
Y. Kharkov, I.A. Morozov
BINP SB RAS, Novosibirsk, Russia
S. Nagaitsev
Fermilab, Batavia, USA

Several families of nonlinear accelerator lattices with integrable transverse motion were suggested recently*. One of the requirements for the existence of two analytic invariants is a special longitudinal coordinate dependence of fields. This paper presents the particle motion analysis when a problem becomes integrable in the normalized polar coordinates. This case is distinguished from the others: it yields an exact analytical solution and has a uniform longitudinal coordinate dependence of the fields (since the corresponding nonlinear potential is invariant under the transformation from the Cartesian to the normalized coordinates). A number of interesting features are revealed: while the frequency of radial oscillations is independent of the amplitude, the spread of angular frequencies in a beam is absolute. A corresponding spread of frequencies of oscillations in the Cartesian coordinates is evaluated via the simulation of transverse Schottky noise.
V. Danilov and S. Nagaitsev, Phys. Rev. ST Accel. Beams 13 084002 (2010).

TUEPPB009

First Measurements of the FACET Coherent Terahertz Radiation Source

radiation, electron, diagnostics, photon

1134

Z. Wu, E. Adli, A.S. Fisher, M.J. Hogan, H. Loos
SLAC, Menlo Park, California, USA

Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515.
The Facility for Accelerator science and Experimental Tests (FACET) at SLAC provides a high peak current, sub-ps bunched beam that is ideal for THz photon generation via coherent transition radiation. This paper presents preliminary characterization of the THz pulses generated by FACET electron beam. A one-micron thick Ti foil has been inserted into the beam path and the radiated photons collected. Michelson spectroscopy yields frequency content spanning from 0.25 THz to 2.3 THz and peaked at around 0.5 THz. Multiple scans at different bunch compression show a monotonic increase of the peak radiation frequency as the electron bunch gets shorter. Using the Kramers-Kronig relation, the temporal profile of the THz pulse is reconstructed from the power spectrum indicating a ~4 picosecond main pulse followed by a long oscillating tail due to the water absorption lines and detector response. Knife-edge scans measure a 4.4 mm x 4.8 mm transverse spot size at the focal point of the THz optical path. The total collected energy per pulse is 0.69 mJ measured by a Joulemeter. Fitting this total energy to the spatiotemporal profile of the THz pulse yields peak e-field amplitude of 1.5 MV/cm.

TUPPC025

Solaris Storage Ring Lattice Optimization with Strong Insertion Devices

lattice, optics, undulator, storage-ring

1218

A.I. Wawrzyniak, C.J. Bocchetta
Solaris, Kraków, Poland
M. Eriksson, S.C. Leemann
MAX-lab, Lund, Sweden

Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Solaris synchrotron light facility under construction in Kraków will be a replica of the 1.5 GeV storage ring of MAX IV. This compact 3rd generation light source has been designed to have an emittance of 6 nmrad and operate with 500 mA stored current for VUV and soft X-Rays production. The lattice design consists of 12 Double Bend Achromats (DBA) with each DBA cell integrated into one solid iron block. Twelve 3.5 m long straight sections are available of which 10 will be equipped in various insertion devices. These devices will differ from those adopted by MAX IV. For X-ray production one or more superconducting wigglers will be used, while APPLE II type undulators will be used for variable polarised light production. The linear and nonlinear lattice dynamics have been studied with these perturbing insertion devices included in the ring and results are presented in this paper.

TUPPC037

Update on LHeC Ring-Ring Optics

sextupole, optics, lattice, resonance

1242

M. Fitterer
KIT, Karlsruhe, Germany
O.S. Brüning, H. Burkhardt, B.J. Holzer, J.M. Jowett
CERN, Geneva, Switzerland
M. Klein
The University of Liverpool, Liverpool, United Kingdom

An update of the LHeC Ring-Ring optics is presented which accounts for chromatic corrections and more flexibility in the tune adjustment.

TUPPC061

Commissioning of a beta∗ Knob for Dynamic IR Correction at RHIC

optics, luminosity, quadrupole, feedback

1314

G. Robert-Demolaize, A. Marusic, S. Tepikian, S.M. White
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
In addition to the recent optics correction technique demonstrated at CERN and applied at RHIC, it is important to have a separate tool to control the value of the beta functions at the collision point (beta∗). This becomes even more relevant when trying to reach high level of integrated luminosity while dealing with emittance blow-up over the length of a store, or taking advantage of compensation processes like stochastic cooling. Algorithms have been developed to allow modifying independently the beta function in each plane for each beam without significant increase in beam losses. The following reviews the principle of such algorithms and their experimental implementation as a dynamic beta-squeeze procedure.

TUPPP014

HiSOR-II, Compact Light Source with a Torus-knot Type Accumulator Ring

lattice, emittance, quadrupole, insertion-device

1635

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

Funding: This work is partially supported by Cooperative and Supporting Program for Researches and Educations in University sponsored by KEK.
We proposed a torus knot type synchrotron radiation ring where the beam orbit is not closed with one turn but return to the starting position after multiple turns around the ring. This ring is capable of having many straight sections and it is advantageous for installation of insertion devices. We named this architecture AMATELAS. We are designing a new ring based on the shape of a (11, 3) torus knot for our future plan HiSOR-II. This ring has eleven 3.6-m-long straight sections though the ring diameter is as compact as 15 m. The achieved emittance is 17.4 nmrad with the lattice having bending magnets with combined function. This level of emittance is as low as the conventional 3rd generation light source. On the other hand, there is a potential problem caused by that the radius of the orbit and focusing force are not constant in the bending magnets. However, we confirmed that it does not make serious influence to the beam by calculating with dividing the bending into several sections. We will compare the parameters of this new ring with the conventional ring which we have designed as the future plan of our facility and evaluate performance as the compact synchrotron light source.

TUPPP021

Orbit Stability at ALBA

insertion-device, wiggler, booster, undulator

1653

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

The synchrotron light source ALBA is in the final stage of the Storage Ring commissioning, with the beamline commissioning well under way. In the month of beam line commissioning, the storage ring has provided an stable beam, with horizontal and vertical stabilities better than the micrometer in both planes in DC and a good reproducibility of the beam position day by day. In this paper we review the performance of the Slow Orbit Feedback, the changes in orbit due to insertion devices, as well as the first measurement using the 10 kHz sampling mode of the Libera BPMs, together with the status of the implementation of the Fast Orbit Feedback system.

TUPPP028

A Study of Girder Alignment with Survey Measurements In the Diamond Storage Ring

survey, storage-ring, closed-orbit, sextupole

1674

M. Apollonio, R. Bartolini, R.T. Fielder, W.J. Hoffman, J. Kay, I.P.S. Martin, B. Singh
Diamond, Oxfordshire, United Kingdom

Using a model of the Diamond storage ring which includes displacements and rotations of the 74 magnet girders an attempt has been made to correlate survey data with the corrector magnet (CM) strengths required for a zero orbit. We then use the model to deduce the most effective girder movements that will bring about a reduction in corrector strength. We describe the results of these studies, and suggest a test with a deliberately displaced girder and the effect on corrector strengths, aimed at enhancing our understanding of the system

TUPPP037

Status of the ALS Brightness Upgrade

lattice, brightness, emittance, insertion-device

1692

C. Steier, B.J. Bailey, A. Biocca, A.T. Black, D. Colomb, N. Li, A. Madur, S. Marks, H. Nishimura, G.C. Pappas, S. Prestemon, D. Robin, S.L. Rossi, T. Scarvie, D. Schlueter, C. Sun, W. Wan
LBNL, Berkeley, California, USA

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) at Berkeley Lab while one of the earliest 3rd generation light sources remains one of the brightest sources for sof x-rays. Another multiyear upgrade of the ALS is currently under way, which includes new and replacement x-ray beamlines, a replacement of many of the original insertion devices and many upgrades to the accelerator. The accelerator upgrade that affects the ALS performance most directly is the ALS brightness upgrade, which will reduce the horizontal emittance from 6.3 to 2.2 nm (2.6 nm effective). This will result in a brightness increase by a factor of three for bendmagnet beamlines and at least a factor of two for insertion device beamlines. Magnets for this upgrade are currently under production and will be installed later this year.

TUPPR068

The Achromatic Telescopic Squeezing Scheme: Basic Principles and First Demonstration at the LHC

optics, sextupole, injection, quadrupole

1978

S.D. Fartoukh, R. De Maria, B. Goddard, W. Höfle, M. Lamont, G.J. Müller, L. Ponce, S. Redaelli, R.J. Steinhagen, M. Strzelczyk, R. Tomás, G. Vanbavinckhove, J. Wenninger
CERN, Geneva, Switzerland
R. Miyamoto
ESS, Lund, Sweden

The Achromatic Telescopic Squeezing (ATS) scheme [1] is a novel squeezing mechanism enabling the production of very low β^* in circular colliders. The basic principles of the ATS scheme will be reviewed together with its strong justification for the High-Luminosity LHC Project. In this context, a few dedicated beam experiments were meticulously prepared and took place at the LHC in 2011. The results obtained will be highlighted, demonstrating already the potential of the ATS scheme for any upgrade project relying on a strong reduction of β^*.
[1] S. Fartoukh, "An Achromatic Telescopic Squeezing (ATS) Scheme For The LHC Upgrade," IPAC'11, WEPC037, p. 2088 (2001).

WEPPC017

Design of a High-Speed Pulsed 324MHz Solid-State Amplifier for Use in a Beam Chopper

resonance, impedance, proton, feedback

2242

S.C. Dillon, B.S. Nobel, C.P. Schach
Tomco Technologies, Stepney, South Australia, Australia

A 324MHz 30kW high-speed pulsed solid-state amplifier has been designed for use in a beam chopper at the Japan Proton Accelerator Complex (J-PARC). This paper discusses the various design challenges and presents the initial performance test results. In particular, the amplifier achieves pulse rise and fall times of less than 15 nanoseconds, is easily upgradeable in power, and withstands 100% power reflection without damage.

WEPPD010

Re-commissioning of the ESRF Storage Ring Vacuum System

vacuum, storage-ring, synchrotron, insertion-device

2516

M. Hahn, I. Parat
ESRF, Grenoble, France

A long shutdown of the accelerators to allow the construction of new buildings marked the phase one of the ESRF upgrade program. A number of vacuum sectors has been modified during this time for repair and maintenance but mainly to increase the brilliance of the synchrotron radiation beams by installing longer insertion device (ID) vessels with non-evaporable getter (NEG) coating and a new In Vacuum Undulator. The paper gives an overview of the modified machine and reports experience with its re-conditioning.

WEPPD015

Saturation Behaviour of the LHC NEG Coated Beam Pipes

vacuum, simulation, injection, site

2525

G. Bregliozzi, V. Baglin, J.M. Jimenez, G. Lanza, T. Porcelli
CERN, Geneva, Switzerland

In the CERN Large Hadron Collider (LHC), about 6 km of the UHV beam pipe are at room temperature and serve as experimental or utility insertions. TiZrV non-evaporable getter (NEG) coating is used to maintain the design pressure during beam operation. Molecular desorption due to dynamic effects is stimulated during protons operation at high intensity. This phenomenon produces an important gas load from the vacuum chamber walls which could lead to a partial or total saturation of the NEG coating. To keep the design vacuum performances and to schedule technical interventions for NEG re-activation, it is necessary to take in account all these aspects and to regularly evaluate the saturation level of the NEG coating. Experimental studies in a typical LHC vacuum sector were conducted in order to identify the best method to assess the saturation level of the beam pipe. Partial saturation of the NEG was performed and the effects in the variations of pressure reading, effective pumping speed, transmission and capture probability are analysed. Finally, based on these results, a detailed analysis of the NEG coating saturation level of some area of the LHC is presented and analysed.

WEPPD042

The Grounding System at TPS

site, synchrotron, emittance, controls

2606

T.-S. Ueng, J.-C. Chang, J.-R. Chen, Y.-C. Lin
NSRRC, Hsinchu, Taiwan

An elaborately designed grounding system has been installed under the TPS construction site. The ground grid was installed sector by sector to comply with the building construction schedule. The ground resistance measurement of each sector was carried out right after the grid installation. The final ground resistance measurement for the whole grounding system was performed also right after its completion. The measured ground resistances of each sector were used to estimate the final TPS ground resistance, and it was compared to the final TPS ground measurement result. Also, the analysis with computer software is used to justify it. The low impedance of TPS grounding system, < 0.15 ohm, is to insure the safety of TPS personnel and instrumentation, also, to reduce the noise of electronic devices.

WEPPD071

The FLUKA LineBuilder and Element DataBase: Tools for Building Complex Models of Accelerator Beam Lines

optics, simulation, injection, proton

2687

A. Mereghetti
UMAN, Manchester, United Kingdom
V. Boccone, F. Cerutti, R. Versaci, V. Vlachoudis
CERN, Geneva, Switzerland

Extended FLUKA models of accelerator beam lines can be extremely complex: heavy to manipulate, poorly versatile and prone to mismatched positioning. We developed a framework capable of creating the FLUKA model of an arbitrary portion of a given accelerator, starting from the optics configuration and a few other information provided by the user. The framework includes a builder (LineBuilder), an element database and a series of configuration and analysis scripts. The LineBuilder is a Python program aimed at dynamically assembling complex FLUKA models of accelerator beam lines: positions, magnetic fields and scorings are automatically set up, and geometry details such as apertures of collimators, tilting and misalignment of elements, beam pipes and tunnel geometries can be entered at user's will. The element database (FEDB) is a collection of detailed FLUKA geometry models of machine elements. This framework has been widely used for recent LHC and SPS beam-machine interaction studies at CERN, and led to a drastic reduction in the time otherwise required to rework old machine models, and to a coherent and traceable description of the inputs used for all the simulations.

WEPPP065

Status of the SSRF Fast Orbit Feedback System

feedback, controls, storage-ring, electron

2855

B.C. Jiang, J. Hou, C.X. Yin, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

The fast orbit feedback system with bandwidth up to 100Hz is under commissioning at SSRF. The main purposes of the system are to suppress the short term orbit stability under sub-micron level and to compensate the orbit distortions caused by changing gaps of the insertion devices. The layout of the system is described and the preliminary commissioning results are given out in this paper.

WEPPP087

The Improvement and Test of Laser Positioning System for TPS Magnets Alignment Inspection

laser, quadrupole, alignment, sextupole

2915

M.L. Chen, J.-R. Chen, H.C. Ho, K.H. Hsu, W.Y. Lai, C.-S. Lin, C.J. Lin, H.C. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu
NSRRC, Hsinchu, Taiwan

A Laser positioning system, consist of a laser, laser position sensing devices (PSD) module and two granite blocks, is developed for the alignment inspection of TPS (Taiwan Photon Source) quadrupole and sextupole magnets during installation on a girder. The PSD module is adapted on the pole center of magnet and is designed to stand for mechanical center of magnets. For high accuracy, eliminating the influence of magnets manufacturing errors between PSD module is a major work. The PSD is mounted on a precise diameter expansible jig to absorb the manufacturing errors. The real roundness of the expansible jig can keep under 3um when diameter is expanded 80um. The PSD position is adjusted and corrected in advance, and then the PSD module center can be identical to the ideal pole position of magnets on the girder within 15um. The magnet will be aligned and adjusted by laser position on PSD. This paper describes how to eliminate the measuring error caused by magnet manufacturing error and the detail of alignment inspection procedure of magnets during the installation on a girder.

THPPC009

Investigation of the Approaches to Measure the RF Cable Attenuation

controls, linac, acceleration, radio-frequency

3290

K. Futatsukawa, Z. Fang, Y. Fukui, T. Kobayashi, S. Michizono
KEK, Ibaraki, Japan
F. Sato, S. Shinozaki
JAEA/J-PARC, Tokai-mura, Japan

In the accelerator facilities, many RF cables are used for the various purposes such as the transmission system and the cavity monitor. The knowledge of the power attenuation in those cables is important role to control RF. In general, the cable attenuation is measured from S parameters to use a network analyzer. However, the control system is located far from the place of the cavities, and it difficult to measure by a network analyzer. Then we investigated other methods to measure the RF cable attenuation.

THPPC073

Development of the Energy-Efficient Solid State RF Power Source for the Jefferson Laboratory CEBAF Linac

controls, klystron, linac, high-voltage

3455

X. Chang, N. Barov, D.J. Newsham, D. Wu
Far-Tech, Inc., San Diego, California, USA

Funding: Work supported by DOE Office of Nuclear Physics, DOE-SBIR #DE-SC0002529
We present the current status of FAR-TECH's Solid State RF Power Source for the Jefferson Laboratory CEBAF Linac. This power source design features up to 8 kW CW RF output power, GaN amplifier stages with high efficiency (>60%), and a compact design to fit existing rack space and cooling requirements at the installation site. We have finished most of the designs and have performed successfully the most critical tests of this project, the 4 to 1 combiner test and the cooling test. FAR-TECH’s solid state amplifier design has high efficiency, a wide range of design frequency (DC-3GHz), and long lifetime, which provides a good RF power source.

THPPD030

Characterization of a Measurement System for Dynamic Effects in Large-aperture SC Quadrupole Magnets

quadrupole, multipole, superconducting-magnet, controls

3569

S. Russenschuck, M. Bajko, M.C.L. Buzio, G. Deferne, O. Dunkel, L. Fiscarelli, D. Giloteaux, L. Walckiers
CERN, Geneva, Switzerland

A new measurement system, based on a large-diameter search-coil rotating in the superfluid helium, a fast digital integrator, a motor drive unit with sliprings, and a flexible software environment was devolped at CERN for the measurement of dynamic effects in superconducting magnets*. This system has made it possible the measure, with a resolution of up to 8 Hz, the multipole field errors due to superconductor magnetization and interstrand coupling currents. In the paper we will present the development and calibration of the measurement system, its installation in the vertical cryostat of CERN's recently refurbished test station, and its application to the US-LARP** built, 120-mm-aperture Nb3Sn quadrupole magnet (HQ) for the upgrade of the LHC insertion regions.
* P. Arpaia et al. Active Comp. of Field Errors within ± 2 PPM in SC Magnets, NIM A, 2011
** H. Felice et al. Design of HQ, a High Field Large Bore Nb3Sn Quad. Magnet for LARP, IEEE TAS, 2009

THPPD059

Conductive EMI Reduction to Kicker Magnet Power Supply in NSRRC

kicker, power-supply, controls, synchrotron

3647

Y.-H. Liu, J.-C. Chang, C.S. Chen, H.H. Chen, J.-R. Chen
NSRRC, Hsinchu, Taiwan

The purpose of this paper is to estimate and reduce the conductive Electromagnetic Interference (EMI) from kicker magnet power supply in TLS. A LISN system was conducted to measure the EMI spectrum of kicker power supply. The EMI noise exceeded FCC standards in some frequency range especially during kicker firing. Reducing EMI level by using different EMI filters were applied. Double pi filter was more efficient than single pi filter. After using filter, the conducted EMI could diminish lower than FCC class B. The experimental results will provide useful information to future TPS pulsed magnet design.

THPPP038

Simulations of the Influence of 4-Rod RFQ Elements on its Voltage Distribution

rfq, simulation, resonance, linac

3818

J.S. Schmidt, B. Koubek, A. Schempp
IAP, Frankfurt am Main, Germany

The influence of tuning methods and other design elements of 4-rod-RFQs on the voltage distribution have been studied during the last months. Every change in the field geometry or the voltage distribution could for example lead to particle losses or a raise in the surface current on single parts of the RFQ. That’s why further research had to be done about the behavior of the 4-rod-RFQ especially in the comparison of structures at 100 or 200 MHz. The results of an analysis which is concentrated on simulations using CST Microwave Studio to evaluate the effects of the overhang of electrodes, modulation and piston tuners on the fields in the RFQ are presented in this paper.

THPPR011

Insertion Device Controls Plan of the Taiwan Photon Source

controls, insertion-device, EPICS, vacuum

3987

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

Insertion device (ID) is a crucial component in third-generation synchrotron light sources, which can produces highly-brilliant, forward-directed and quasi-monochromatic radiation over a broad energy range for various experiments. In the phase I of the Taiwan Photon Source (TPS) project, ten insertion devices (IDs) will be planned, constructed, and installed for the first seven beamlines. The control system for all the IDs is based on the EPICS architecture. The main control components include the motor with encoder for gap adjustment, trim coil power supply for corrector magnets, temperature sensor for ID environmental monitoring and baking (only for In-Vacuum Undulator), and interlock system (limit switches, tilt sensor) for safety. The progress of the controls plan will be summarized in this report.

THPPR036

Quench Limit Calculations for Steady State Heat Deposits in LHC Inner Triplet Magnets

quadrupole, proton, luminosity, simulation

4050

D. Bocian
IFJ-PAN, Kraków, Poland
F. Cerutti, B. Dehning, A.P. Siemko
CERN, Geneva, Switzerland

In hadron colliders such as the LHC, the energy deposited in the superconductors by the particles lost from the beams or coming from the collision debris may provoke quenches detrimental to the accelerator operation. A Network Model is used to simulate the thermodynamic behavior of the superconducting magnets. In previous papers the validations of network model with measurements performed in the CERN and Fermilab magnet test facilities were presented. This model was subsequently used for thermal analysis of the current LHC inner triplet quadrupole magnets for beam energy of 3.5 TeV and 7 TeV. The detailed study of helium cooling channels efficiency for energy deposits simulated with FLUKA is presented. Some conclusions are drawn on expected inner triplet magnets quench limit.