IPAC2012 - List of Keywords (lattice)

Paper	Title	Other Keywords	Page
MOOAB03	FACET First Beam Commissioning	linac, emittance, damping, sextupole	46
	G. Yocky, C.I. Clarke, W.S. Colocho, F.-J. Decker, M.J. Hogan, N. Lipkowitz, J. Nelson, P.M. Schuh, J.T. Seeman, J. Sheppard, H. Smith, T.J. Smith, M. Stanek, Y. Sun, J.L. Turner, M.-H. Wang, S.P. Weathersby, G.R. White, U. Wienands, M. Woodley SLAC, Menlo Park, California, USA
	Funding: Work supported by U.S. Department of Energy, Contract DE-AC02-76SF00515. The FACET (Facility for Advanced aCcelerator Experimental Tests) facility at SLAC has been under Construction since summer 2010. Its goal is to produce ultrashort and transversely small bunches of very high intensity (20kA peak current) to facilitate advanced acceleration experiments like PWFA and DLA. In June of 2011 the first electron beam was brought into the newly constructed bunch-compression chicane. Commissioning work included restarting the linac and damping ring, verifying hardware, establishing a good beam trajectory, verifying the optics of the chicane, commissioning diagnostic devices for transverse and longitudinal bunch size, and tuning up the beam size and bunch compression. Running a high-intensity beam through the linac without BNS damping and with large energy spread is a significant challenge. Optical aberrations as well as wakefields conspire to increase beam emittance and the bunch compression is quite sensitive to details of the beam energy and orbit, not unlike what will be encountered in a linear-collider final-focusing system. In this paper we outline the steps we took while commissioning as well as the challenges encountered and how they were overcome.
	Slides MOOAB03 [9.167 MB]

MOEPPB003	Status of the PRISM FFAG Design for the Next Generation Muon-to-Electron Conversion Experiment	solenoid, target, injection, proton	79
	J. Pasternak, A. Alekou, M. Aslaninejad, R. Chudzinski, L.J. Jenner, A. Kurup, Y. Shi, Y. Uchida Imperial College of Science and Technology, Department of Physics, London, United Kingdom R. Appleby, H.L. Owen UMAN, Manchester, United Kingdom R.J. Barlow University of Huddersfield, Huddersfield, United Kingdom K.M. Hock, B.D. Muratori Cockcroft Institute, Warrington, Cheshire, United Kingdom D.J. Kelliher, S. Machida, C.R. Prior STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom Y. Kuno, A. Sato Osaka University, Osaka, Japan J.-B. Lagrange, Y. Mori Kyoto University, Research Reactor Institute, Osaka, Japan M. Lancaster UCL, London, United Kingdom C. Ohmori KEK, Tokai, Ibaraki, Japan T. Planche TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada S.L. Smith STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom H. Witte BNL, Upton, Long Island, New York, USA T. Yokoi JAI, Oxford, United Kingdom
	The PRISM Task Force continues to study high intensity and high quality muon beams needed for next generation lepton flavor violation experiments. In the PRISM case such beams have been proposed to be produced by sending a short proton pulse to a pion production target, capturing the pions and performing RF phase rotation on the resulting muon beam in an FFAG ring. This paper summarizes the current status of the PRISM design obtained by the Task Force. In particular various designs for the PRISM FFAG ring are discussed and their performance compared to the baseline one, the injection/extraction systems and matching to the solenoid channels upstream and downstream of the FFAG ring are presented. The feasibility of the construction of the PRISM system is discussed.

MOPPC008	LHC Optics Determination with Proton Tracks Measured in the Roman Pots Detectors of the TOTEM Experiment	proton, optics, scattering, coupling	136
	H. Niewiadomski, H. Burkhardt CERN, Geneva, Switzerland F.J. Nemes KFKI, Budapest, Hungary
	The TOTEM experiment at the LHC is equipped with near beam movable devices – called Roman Pots (RP) – which detect protons scattered at the interaction point (IP) arrived to the detectors through the magnet lattice of the LHC. Proton kinematics at IP is reconstructed from positions and angles measured by the RP detectors, on the basis of the optical functions between IP and the RP locations. The precision of optics determination is therefore of the key importance for the experiment. TOTEM developed a novel method of machine optics determination making use of angle-position distributions of elastically scattered protons observed in the RP detectors. The method has been successfully applied to the data samples registered in 2010 and 2011. The studies have shown that the transport matrix could be estimated with a precision better than 1%.

MOPPC013	Optics and Lattice Optimizations for the LHC Upgrade Project	optics, luminosity, ion, insertion	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.

MOPPC020	Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice	quadrupole, multipole, dynamic-aperture, target	169
	Y. Jiao, Y. Cai, Y. Nosochkov, M.-H. Wang SLAC, Menlo Park, California, USA R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh CERN, Geneva, Switzerland
	Funding: This work is supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP). It has been proposed to implement an Achromatic Telescopic Squeezing (ATS) scheme* in the high luminosity LHC lattice to reduce the beta functions at the Interaction Points (IP) up to a factor of 8. As a consequence, the nominal 4.5-km peak beta functions reached in the inner triplets at collision will be increased by the same factor. This therefore justifies the installation of new, larger aperture superconducting triplet quadrupoles. These higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture. To maintain the acceptable dynamic aperture, the effects of the triplet multipole field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called “4444” collision optics of the ATS scheme, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplets’ field quality is studied and presented in details. * S. Fartoukh, “An Achromatic Telescopic Squeezing (ATS) Scheme for LHC Upgrade”, Proc. of IPAC11, p. 2088 (2011).

MOPPC022	Off-momentum Dynamic Aperture for Lattices in the RHIC Heavy Ion Runs	luminosity, ion, heavy-ion, emittance	175
	Y. Luo, M. Bai, M. Blaskiewicz, W. Fischer, X. Gu, A. Marusic, T. Roser, S. Tepikian, S.Y. Zhang 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 this article we calculate and compare the off-momentum dynamic aperture for lattices with different phase advances per FODO cell in the RHIC heavy ion runs. A lattice with an increased phase advance was adopted in 2008-2011 to reduce transverse emittance growth rates from intra-beam scattering. However, during these runs, a large beam loss was observed with longitudinal RF re-bucketing which increased the momentum spread. With operational transverse stochastic cooling in the 2011 RHIC heavy ion run, the transverse intra-beam scattering emittance growth was eliminated, and the beam loss during stores was determined by the off-momentum aperture and burn-off from luminosity. We investigate the possibilities to increase the off-momentum dynamic aperture that would lead to an increase in the integrated luminosity.

MOPPC026	Simulations of Coherent Beam-Beam Effects with Head-on Compensation	electron, resonance, proton, simulation	187
	S.M. White, W. Fischer, Y. Luo BNL, Upton, Long Island, New York, USA
	Funding: Work partially supported by Brookhaven Science Associates, LARP, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Electron lenses are foreseen to be installed in RHIC in order to mitigate the head-on beam-beam effects. This would allow operation with higher bunch intensity and result in a significant increase in luminosity. We report on recent strong-strong simulations that were carried out using the RHIC upgrade parameters to assess the impact of coherent beam-beam effects in the presence of head-on compensation.

MOPPC029	Off-momentum Beat-beat Correction in the RHIC Proton Run	sextupole, quadrupole, simulation, proton	196
	Y. Luo, M. Bai, W. Fischer, A. Marusic, K. Mernick, 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 this article we will present the measurement and correction of the off-momentum β^*-beat in the RHIC proton run. The beta-beat will be measured with the AC dipole and by shifting RF frequency. We will focus on the correction of the off-momentum beta-beat at the interaction points IP6 and IP8 with the arc chromatic sextupole families. The effects of the off-momentum beta-beat correction on the global chromaticities and dynamic aperture will be estimated through beam experiments and the numerical simulation.

MOPPC030	Status of the Decay Ring Design for the IDS Neutrino Factory	injection, kicker, insertion, 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)

MOPPC049	Status of the Non-scaling Fixed Field Alternating Gradient Ring Design for the International Design Study of the Neutrino Factory	factory, acceleration, septum, electron	241
	J.S. Berg, H. Witte BNL, Upton, Long Island, New York, USA M. Aslaninejad, J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom N. Bliss, A.J. Moss STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom S.M. Pattalwar STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The International Design Study of the Neutrino Factory is working towards delivering the optimized design of the neutrino factory facility to be presented in the Reference Design Report (RDR) in 2013. In the current baseline design a linear non-scaling fixed field alternating gradient accelerator (FFAG) was chosen as an efficient solution for the final muon acceleration. We describe updates to the design since our previous report. We report on beam dynamics studies on the lattice. We describe recent work on the engineering for the lattice, and the results of a recent first pass at a cost estimate for the machine. Finally, we describe how an FFAG may be applicable to a lower energy neutrino factory in light of recent experimental results regarding the value of the theta(13) neutrino mixing angle. J. S. Berg et al., in Proceedings of IPAC2011, San Sebastian, Spain, 832. ** F. P. An et al., Phys. Rev. Lett. 10⁸, 171803 (2012); J. K. Ahn et al., arXiv:1204.0626v2 [hep-ex] (2012).

MOPPC050	The International Design Study for the Neutrino Factory	factory, target, proton, acceleration	244
	K.R. Long, J.K. Pozimski Imperial College of Science and Technology, Department of Physics, London, United Kingdom J.S. Berg BNL, Upton, Long Island, New York, USA
	A neutrino factory is a facility for producing a large neutrino flux from the decay of high energy muons. The International Design Study for the Neutrino Factory (IDS-NF) aims to produce a reference design report for such a facility. The report will contain the physics motivation for the facility, describe the accelerator and detector, and estimate the cost for the facility. We will briefly discuss the physics capabilities for a neutrino factory, including how recent neutrino physics results affect our understanding of a neutrino factory's performance and advantages. We will give an overview of our baseline design for the accelerator facility. We will then outline the most significant areas of progress in our studies of the accelerator subsystems. Paper submitted on behalf of the International Design Study for the Neutrino Factory collaboration.

MOPPC053	Modeling of Bending Magnets for SIRIUS	dipole, simulation, multipole, sextupole	250
	X.R. Resende, R. Basílio, L. Liu, P.P. Sanchez, G. Tosin LNLS, Campinas, Brazil
	The new Brazilian synchrotron source, Sirius, will be a 3 GeV storage ring with a triple bend lattice with a minimum emittance of 1.7 nm rad. The ring dipoles are excited with permanent magnets. The middle bend has a small 1.4 degree slice in its center with 1.94 T field and serve as an additional hard X-ray source with critical energy of 11.6 keV. Other bending magnets have low 0.50 T field with gradients, allowing for a further emittance reduction. The bending slice shows a longitudinal profile with no uniform field plateau and with long-range fringe fields which are coupled with the fields of neighbouring dipoles. To take into account the interaction of the field-intersecting dipoles, realistic 3D models of the magnets have been created and their field configuration solved using finite element techniques. Field maps calculated from the 3D magnet models were used for the construction of segmented models of bend elements in beam dynamics codes.

MOPPC063	Computation of the 2D Transverse Wake Function of an Electron Cloud for Different Parameters	electron, simulation, dipole, wakefield	280
	A. Markoviḱ, G. Pöplau, U. van Rienen Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany
	Funding: Work supported by DFG under contract number RI 814/20-2. A PIC simulation of the interaction of a positive charged bunch with an e-cloud yields the wake kick from the electrons on the tail particles of the bunch. The wake is induced from a certain offset in the transverse position of the head parts of the bunch which perturb the electron distribution. Such a pre-computed wake functions of each offset part of the bunch are forming a matrix which could be used for investigating single bunch stability under several assumptions. In this paper we investigate the linear scalability of the kick with the offset value. Furthermore we investigate the wake values for different realistic electron densities. Another important parameter for realizing the single bunch stability simulation is the optimal number of bunch slices in longitudinal direction. Here we study the thickness of the slices in conjunction with the mobility of the electrons around the beam axis.

MOPPC076	New Features of the Parallel TRACY for Nonlinear Beam Dynamics	dynamic-aperture, sextupole, closed-orbit, betatron	310
	M.-S. Chiu, H.-P. Chang NSRRC, Hsinchu, Taiwan
	The TRACY code is used to analyze and simulate the nonlinear beam dynamics of the designed lattice. To speed up the lattice design flow, we parallelized the TRACY by MPI and developed a GUI by GTK+ to integrate the functions of TRACY and added a function of nonlinear optimization adapted from OPA, which is used to optimize the nonlinear driving terms by powell algorithm. The GUI is used for parameter input and data visualization. The procedures of nonlinear optimization and beam dynamics analysis are integrated and streamlined. Users do not need to write and compile the code any more. The results will be demonstrated in this report.

MOPPC077	Simulation and Analysis of the Beam Signal in Taiwan Photon Source Booster	booster, betatron, multipole, synchrotron	313
	C.C. Chiang, H.-P. Chang, P.J. Chou NSRRC, Hsinchu, Taiwan S.-Y. Lee IUCEEM, Bloomington, Indiana, USA
	The TPS (Taiwan Photon Source) booster is a combined function FODO lattice with six super-periods; the total circumference is 496.8 m. To prepare the analysis tools for beam commissioning, we simulate the TPS booster turn-by-turn BPM data with two programs, MAD-X PTC and Tracy-2.6, which are for both DC (constant beam energy) and AC (beam energy in regular ramping) modes. We analyze the simulation data with MIA (Model Independent Analysis) and ICA (Independent Component Analysis), in order to reconstruct beam parameters like beta function, phase advance, dispersion, etc. We include multipole errors, alignment errors, BPM noises or other noises in simulation, and try to design a good strategy for real data analysis.

MOPPC078	Simulation Studies of Injection Scheme in TPS Storage Ring	injection, simulation, storage-ring, alignment	316
	Y.C. Lee, H.-P. Chang, P.J. Chou NSRRC, Hsinchu, Taiwan
	Funding: NSRRC, Hsinchu, Taiwan. The baseline lattice of TPS storage ring was finalized in October 2009. Later upon users’ request, we plan to implement the double mini-βy lattice in three 12-m straight sections of TPS storage ring. These locations were chosen to maintain the symmetry of the storage ring lattice. Particle tracking for the first few turns were used to check the injection scheme of storage ring, including errors introduced in manufacturing and installation process. Results of simulation studies will be presented.

MOPPC080	Modeling Space Charge in an FFAG with Zgoubi	space-charge, emittance, acceleration, synchrotron	322
	S.C. Tygier, R. Appleby, H.L. Owen UMAN, Manchester, United Kingdom R.J. Barlow University of Huddersfield, Huddersfield, United Kingdom
	The Zgoubi particle tracker uses a ray tracing algorithm that can accurately track particles with large offset from any reference momentum and trajectory, making it suitable for FFAGs. In high current FFAGs, for example an ADSR driver, space charge has a significant effect on the beam. A transverse space charge model was added to Zgoubi using the interface pyZgoubi. The magnets are sliced and a space charge kick is applied between each slice. Results are presented for an ADSR driver lattice.

MOPPC083	LinguaFranca - A Graphical User Interface for Accelerator Modeling	simulation, quadrupole, optics, collider	331
	T.J. Roberts Muons, Inc, Batavia, USA
	This is a proposed project to develop an innovative Graphical User Interface that permits users to construct, explore, optimize, and evaluate accelerator systems efficiently and effectively. While it will be designed with students in mind, accelerator physicists will also find it useful in dealing with the plethora of modeling tools and their different languages. The internal representation of the system is specifically designed to be useable as a text-based description of the system, and to make it easy for users to interface it to essentially any accelerator-modeling tool, regardless of its description language. Many accelerator designers have expressed frustration with the current “Tower of Babel” among modeling programs, and this project will address that directly. In particular, this will make it straightforward to use fast but less realistic programs to design and optimize a system, and then use slower but more realistic programs to evaluate its performance. Graphical interfaces are emphasized, making it easy to construct the system graphically, display the system and its beam, and use on-screen controls to vary parameters and observe their effects immediately.

MOPPC086	Accelerator Simulation - Beyond High Performance Computing	target, simulation, site, emittance	340
	S. James, G.M. Jung, B.C. Li, K. Muriki, H. Nishimura, Y. Qin, K. Song, C. Sun LBNL, Berkeley, California, USA
	Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Accelerator modeling and simulation studies heavily rely on High Performance Computing (HPC). Public Cloud computing has opened a new service horizon for HPC by offering an on-demand, Virtual Private Cloud (VPC). Previously, we investigated using Amazon HPC public Cloud for lattice optimization applications and evaluated performance. In this research, we use the Amazon VPC technology to extend local HPC resources to provide a seamless, hybrid, and secure environment when the demand for computing capacity spikes. C. Sun et al., "HPC Cloud Applied to Lattice Optimization," Proc. PAC2011, New York, WEP151, p. 1767 (2011).

MOPPC095	XAL's Online Model at ReA3 to Understand Beam Performance	linac, simulation, cavity, cryomodule	358
	C. Benatti NSCL, East Lansing, Michigan, USA P. Chu, M.J. Syphers, X. Wu FRIB, East Lansing, Michigan, USA
	Funding: This material is based on work supported by the National Science Foundation under Grant No. PHY-1102511 and by Michigan State University. The ReA3 facility at the NSCL at MSU has been designed to reaccelerate rare isotope beams to 3MeV/u. ReA3 consists of a charge to mass selection section, a normal conducting RFQ, a superconducting linac, and transport beam lines that deliver the beam to the experiments. The beam optics designs were developed using COSY and IMPACT. A code with an online model capable of interacting with the control system, such as XAL, developed at SNS, would be ideal for studying this system. New elements have been added to XAL’s already extensive list of supported devices in order to model elements unique to the NSCL. The benchmarking process has been completed for establishing the use of XAL’s Online Model at the NSCL, and preliminary results from its use at the ReA3 control room have been obtained. The development of applications to fit the needs of the program is ongoing. A summary of the benchmarking process is presented including both transverse and longitudinal studies. J. Galambos et al., Proc. PAC 2005, p. 79, (2005); doi: 10.1109/PAC.2005.1590365.

MOPPD002	Ultra-low Energy Storage Ring at FLAIR	extraction, antiproton, storage-ring, ion	367
	C.P. Welsch, D. Newton, M.R.F. Siggel-King Cockcroft Institute, Warrington, Cheshire, United Kingdom O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov MPI-K, Heidelberg, Germany J. Harasimowicz, M. Putignano, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged. The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 10⁶ were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.

MOPPD019	Vertical Orbit Excursion FFAG Accelerators with Edge Focussing	proton, injection, neutron, dynamic-aperture	406
	S.J. Brooks STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	FFAGs with vertical orbit excursion (VFFAGs) provide a promising alternative design for the magnets in fixed-field machines. They have a vertical magnetic field component that increases with height in the vertical aperture, yielding a skew quadrupole focussing structure. The end fields of such magnets with edge angles provide an alternating gradient without the need for reverse bends, thus reducing the machine circumference. Similarly to spiral scaling horizontal FFAGs (but unlike non-scaling versions), the machine has fixed tunes and no intrinsic limitation on momentum range. Rings capable of boosting the 150mm.mrad geometric emittance beam from the ISIS proton synchrotron to 3, 5 and 12GeV using superconducting magnets are presented, the latter corresponding to 2.5MW beam power.

MOPPD020	A Model for a High-Power Scaling FFAG Ring	injection, dynamic-aperture, extraction, proton	409
	G.H. Rees, D.J. Kelliher, S. Machida, C.R. Prior, S.L. Sheehy STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	High-power FFAG rings are under study to serve as drivers for neutron spallation, muon production, and accelerator-driven reactor systems. In this paper, which follows on from earlier work, a 20 - 70 MeV model for a high-power FFAG driver is described. This model would serve as a test bed to study topics such as space charge and injection in such rings. The design incorporates a long straight to facilitate H^- charge exchange injection. The dynamic aperture is calculated in order to optimize the working point in tune space. The injection scheme is also described. A separate design for an ISIS injector, featuring a novel modification to the scaling law, was also studied. G.H. Rees and D.J. Kelliher, “New, high power, scaling, FFAG driver ring designs” HB2010, Morschach, September 2010, MOPD07, p. 54, http://www. JACoW.org

MOPPP010	Investigation of CSR Effect for Femtosecond Electron Bunches in an Isochronous Accumulator Ring	simulation, radiation, electron, linac	589
	N.Y. Huang, H. Hama, F. Hinode, S. Kashiwagi, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
	Coherent synchrotron radiation (CSR) from a novel isochronous ring is a candidate for light source that provides THz radiation with high average flux. A compact isochronous accumulator ring (IAR) for the maximum beam energy of 54 MeV has been designed so as to eliminate the 0th order momentum compaction factor, and the 1st order of it is mostly compensated. In addition, the path length deviation due to betatron motion is mostly compensated in a cell. Though there is no RF cavity in IAR, the injected beam may circulate for certain number of turns. Multi experimental stations can be allocated like synchrotron radiation facilities. However, it has been well known that instability due to the CSR wake field is an issue for the beam stability in the ring operated at low alpha mode. Therefore, a study for effects of the CSR wake on the bunch length and shape in IAR has been in progress. It has turned out that the maximum longitudinal field strength created by CSR would be ~ 0.15 MV/m for the case of 100 fs Gaussian bunch, which is considerably an intense field. To protect the bunch shape from the CSR wake, further study is definitely required.

MOPPP057	Optimization of the Low-emittance Lattice of the APS Booster Synchrotron	booster, emittance, injection, sextupole	690
	C. Yao, V. Sajaev, N. Sereno, H. Shang ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06- CH11357. The APS booster is a 7GeV electron synchrotron. Three lattices have been originally designed with a nominal beam emittance of 132, 109, and 92 nm, respectively. In the past we have mostly operated the booster with the 132 nm lattice because of its better stability. The lower-emittance lattices are not utilized. In early 2010 we upgraded the booster ramp correction and reduced the 360Hz current ripples of the ramp supplies. Current ramp errors have been significantly reduced. This raises our interest in running the low- emittance lattice to improve APS storage ring injection efficiency and reduce radiation losses. This report presents the optimization methods and measurement results of booster beam performance of the booster 92nm lattice.

MOPPP058	Improvements to the APS Booster Injection Controllaw Process	injection, controls, booster, synchrotron	693
	C. Yao, F. Lenkszus, H. Shang, S. Xu ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06- CH11357. The APS booster is a 7-GeV electron synchrotron with a 0.5-second cycle time. The booster runs a set of injection control programs that corrects the injection beam trajectory based on the beam history of two BPMs. An IOC process calculates the I and Q components of beam oscillation from turn-by turn beam position samples over the first 64 turns. The booster injection control programs apply phase, energy, and transverse angle correction based on the result of the IOC processing. The initial system was installed in 2007. Since installation the system has mostly worked well for normal user operations. However, occasionally the system has yielded inconsistent results. Recently we reviewed the signal and processes involved in this system and made necessary upgrades to some components, including selection of a new set of two input BPMs, optimization of FFT parameters, and addition of an injection tune control program. These upgrades have significantly improved the effectiveness and consistency of the system. We report the findings, analysis, and results.

MOPPP060	Top-Off Mode of Operations: Setting Limits on the Extracted Beam Energy by Constraining Currents of Multiple Booster Dipole Power Supplies.	dipole, booster, extraction, injection	696
	T.V. Shaftan BNL, Upton, Long Island, New York, USA
	In preparation for top-off mode of the NSLS-II operations we have studied impact of errors in the dipole power supply current on the extracted beam energy, which has to be interlocked so to satisfy the safety requirements. The NSLS-II booster dipole circuits are combined into 3 independent PS circuits, which adds complexity to the analysis of the extracted beam energy limits.

MOPPP064	Challenges of Quasiperiodic APPLE Undulators	undulator, polarization, synchrotron, synchrotron-radiation	705
	J. Bahrdt HZB, Berlin, Germany S. Sasaki HSRC, Higashi-Hiroshima, Japan
	APPLE undulators have become workhorses in many synchrotron radiation facilities for the production of variably polarized light. In helical mode higher harmonics are not produced. In linear mode (horizontal, vertical, inclined) higher harmonics may contaminate the first harmonic and spoil the quality of experimental data. Planar undulators employing a quasiperiodic magnetic structure have been built and they are successfully operated at several places. The implementation of a quasiperiodic lattice in an APPLE undulator is more complicated since the device is operated in various modes of operation. The proposed APS-upgrade includes a quasiperiodic APPLE undulator which is intended to be operated in the range 2.4-27 keV. A detailed analysis of the magnetic and spectral performance of this device is presented.

MOPPR001	Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring	storage-ring, electron, polarization, synchrotron	771
	K.P. Wootton, R.P. Rassool The University of Melbourne, Melbourne, Australia M.J. Boland, Y.E. Tan ASCo, Clayton, Victoria, Australia W.J. Corbett, M.H. Donald, X. Huang, R.R. Ortiz, J.A. Safranek, K. Tian SLAC, Menlo Park, California, USA
	Accurate electron beam energy measurements are valuable for precision lattice modelling of high-brightness light sources. At SPEAR3 the beam energy was measured using the resonant spin depolarisation method with striplines to resonantly excite the spin tune and a sensitive NaI scintillator beam loss monitor was used to detect resulting changes in Touschek lifetime. Using the combined apparatus an electron beam energy of 2.997251(7) GeV was measured, giving a relative uncertainty better than 3x10^-6. The measured momentum compaction factor was found to be in close agreement with the numerical model value using rectangular defocussing gradient dipoles with measured magnetic field map profiles. In this paper we outline the chosen experimental technique, with emphasis on its applicability to electron storage rings in general.

MOPPR036	Correlation Analysis of Beam Diagnostic Measurements in SSRF	status, diagnostics, feedback, background	858
	Z.C. Chen, Y.B. Leng, Y.B. Yan SSRF, Shanghai, People's Republic of China B.P. Wang SINAP, Shanghai, People's Republic of China
	Funding: Supported by National Natural Science Foundation of China (11075198) Signals from various probes of the beam diagnostic system in Shanghai Synchrotron Radiation Facility (SSRF) were processed with correlation analysis algorithms. The resulting data allowed us to sort the probes by confidence, which means the stable and accurate signals could be separated from the faulty or noisy ones. And the beam dynamics measurements became electronic instrument free at the same time. This makes it possible to eliminate bad Beam Position Monitors (BPM) from the feedback system, offer a more confident set of beam parameters and estimate useful global information by extracting the relationship between some probes.

MOPPR079	Horizontal Beam-size Measurements at CESR-TA Using Synchrotron-light Interferometer	emittance, synchrotron, synchrotron-radiation, scattering	972
	S. Wang, J.V. Conway, D.L. Hartill, M.A. Palmer, D. L. Rubin CLASSE, Ithaca, New York, USA R.F. Campbell, R. Holtzapple CalPoly, San Luis Obispo, California, USA
	Funding: DOE Award DE-FC02-08ER41538 NSF Award (PHY-0734867) NSF Award (PHY-1002467) NSF Award (PHY-1068662). A horizontal beam profile monitor utilizing visible synchrotron radiation from a bending magnet has been designed and installed in CESR. The monitor employs a double-slit interferometer which has been successfully implemented to measure horizontal beam sizes over a wide range of beam currents. By varying the separation of the slits, beam sizes ranging from 50 to 500 microns can be measured with a resolution of approximately 5 microns. The method for extracting the horizontal beam size from the interference pattern is presented and its application to intrabeam scattering studies is described. A configuration for measuring the small vertical beam size is also discussed.

TUYB03	FFAG Experience and Future Prospects	acceleration, proton, focusing, betatron	1054
	Y. Mori Kyoto University, Research Reactor Institute, Osaka, Japan
	This talk should outline the various FFAG accelerators that have been constructed, and discuss the operational experience with different machines. Common issues should be identified, and contrasting experiences highlighted. A frank assessment of the capability of FFAGs to meet the requirements for applications such as ion therapy, accelerator-driven subcritical reactors, and muon colliders should be followed by a description of the main objectives and challenges for future R&D.
	Slides TUYB03 [14.162 MB]

TUOBB02	Commissioning of the PLS-II	insertion, insertion-device, storage-ring, power-supply	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]

TUOAC03	Status of a Single-Aperture 11 T Nb3Sn Demonstrator Dipole for LHC Upgrades	dipole, collimation, status, magnet-design	1098
	A.V. Zlobin, N. Andreev, G. Apollinari, E.Z. Barzi, R. Bossert, G. Chlachidze, V. Kashikhin, A. Nobrega, I. Novitski, D. Turrioni, R. Yamada Fermilab, Batavia, USA B. Auchmann, M. Karppinen, L. Oberli, L. Rossi, D. Smekens CERN, Geneva, Switzerland
	Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy The planned upgrade of the LHC collimation system includes two additional collimators to be installed in the dispersion suppressor areas of points 2, 3 and 7. The necessary longitudinal space for the collimators could be provided by replacing some 8.33 T NbTi LHC main dipoles with 11 T dipoles based on Nb3Sn superconductor and compatible with the LHC lattice and main systems. To demonstrate t his possibility Fermilab and CERN have started in 2011 a joint R&D program with the goal of building by 2014 a 5.5-m long twin-aperture dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m long single-aperture demonstration dipole with the nominal field of 11 T at the LHC nominal current of ~11.85 kA and 60 mm bore with ~20% margin. This paper describes the design, construction and test results of the single-aperture Nb3Sn demonstrator model for the LHC collimation system upgrade.
	Slides TUOAC03 [5.812 MB]

TUEPPB003	Nonlinear Accelerator with Transverse Motion Integrable in Normalized Polar Coordinates	simulation, focusing, insertion, 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).*

TUEPPB005	Novel Technique of Suppressing TBBU in High-energy ERLs	linac, HOM, SRF, electron	1122
	V. Litvinenko BNL, Upton, Long Island, New York, USA
	Energy recovery linacs (ERLs) is emerging generation of accelerators promising revolutionize the fields of high-energy physics and photon sciences. One potential weakness of these devices is transverse beam-breakup instability, which may severely limit available beam current. In this paper I am presenting novel idea of using natural chromaticity in ERL arcs to suppressing TBBU instabilities. I present the theory of the process and two exact cases demonstrating that the threshold of TBBU instability could be raised by my orders of magnitude using this method. * V.N. Litvinenko, Chromaticity of the lattice and beam stability in energy recovery linacs, submitted to PR ST-AB

TUPPC004	Study of a Lattice with a Lower Emittance at SOLEIL	emittance, dipole, optics, betatron	1155
	R. Nagaoka, P. Brunelle, A. Nadji, L.S. Nadolski SOLEIL, Gif-sur-Yvette, France
	The paper introduces the first preliminary feasibility study made at SOLEIL towards a possible future upgrade of the lattice in furthermore reducing the horizontal emittance, so to raise the storage ring performance. The approach taken is to employ whatever emittance reduction methods available, by respecting the given constraints on the lattice structure and the optics, particularly the circumference, insertion device straights, the required optics behavior as well as its tunability. Specifically, the possibility of introducing superbends into the double bend lattice is pursued, which are beneficial to hard X-ray users and could simultaneously help reducing the emittance thanks to its longitudinally varying field profile. Although the present study shall mainly focus on the linear properties of the optical solutions found, optimization of nonlinear optics is also discussed in view of the large dependence of the latter on the former.

TUPPC005	Optimization of the SIS100 Nonlinear Magnet Scheme for Slow Extraction	extraction, sextupole, octupole, dynamic-aperture	1158
	A. Saa Hernandez, M.M. Kirk, D. Ondreka, N. Pyka, S. Sorge, P.J. Spiller GSI, Darmstadt, Germany
	The SIS100 superconducting synchrotron was initially planned mainly for fast extraction of protons and heavy ions. Due to the delay of the construction of the SIS300 synchrotron, SIS100 has to be able to provide slowly extracted heavy ion beams to the experiments. To improve the robustness of the slow extraction from SIS100, a lattice review was performed, resulting in an optimization of the nonlinear magnet scheme. In the original scheme the Hardt condition cannot be established due to a collapse of the dynamic aperture caused by the chromatic sextupoles. In the optimized scheme the positions of the chromatic sextupoles are modified and octupoles are employed to compensate the second order effects of these sextupoles. In addition, the number of resonance sextupole magnets is reduced. With the new scheme, the Hardt condition can be established, leading to higher extraction efficiency. The separatrix can be freely adjusted, and closed orbit control is improved.

TUPPC013	Optimization of Lower Emittance Optics for the SPring-8 Storage Ring	optics, emittance, photon, brilliance	1182
	Y. Shimosaki, K.K. Kaneki, M. Masaki, T. Nakamura, H. Ohkuma, J. Schimizu, K. Soutome, S. Takano, M. Takao JASRI/SPring-8, Hyogo-ken, Japan
	A design work of the present SPring-8 storage ring is in progress to improve its performance. The linear optics has been changed to reduce the natural emittance below the nominal of 3.4 nmrad at 8 GeV, and the nonlinear optics has been optimized with a genetic algorithm to suppress the amplitude-dependent tune shifts and to enlarge the dynamic aperture. As a preliminary study, the optics with the natural emittance of 2.4 nmrad at 8 GeV has been examined, theoretically and experimentally. In this optics, 1.5 times higher brilliance for 10 keV photons than the present can theoretically be expected for the standard undulator beamline. The improved optics design and its beam performance will be presented in detail. In this presentation, a optics for a future upgrade of the SPring-8 (SPring-8 II) will not be discussed, which is a full-scale major lattice modification, while the method we used in optimizing the nonlinear optics can also be adopted to the SPring-8 II. Y. Shimosaki et al., "Design Study of Nonlinear Optics for a Very Low-emittance Lattice of the SPring-8 II," these proceedings.

TUPPC014	Design Study of Nonlinear Optics for a Very Low-emittance Lattice of the SPring-8 II	sextupole, emittance, resonance, optics	1185
	Y. Shimosaki, K.K. Kaneki, T. Nakamura, H. Ohkuma, J. Schimizu, K. Soutome, M. Takao JASRI/SPring-8, Hyogo-ken, Japan
	A feasibility of a very low-emittance storage ring has been studied for an upgrade project, SPring-8 II. Its ultimate goal is to provide a superior brilliance for 0.5 ~ 100 keV photons. A sextupole bend lattice with the natural emittance of 70 pmrad at 6 GeV has been examined as the first candidate. The nonlinear optics has been optimized to enlarge the dynamic aperture by correcting nonlinear resonances based on an isolated resonance Hamiltonian with thick lens approximation, and by non-interleaved sextupole method. A genetic algorithm, which has been examined to improve the performance of the present SPring-8, will be adopted for detailed optimization of the tunes and sextupole strength to adjust the non-interleaved scheme and to correct higher order resonances. The correction scheme of nonlinear optics and its results will be presented in detail. Y. Shimosaki et al., IPAC’11, TUOAB01, p. 942 (2011). **Y. Shimosaki et al., "Optimization of Lower Emittance Optics for the SPring-8 Storage Ring", these proceedings.

TUPPC015	Local Modification of Lattice of a Long Straight Section for Installing Small Gap In-vacuum Undulators at SPring-8	betatron, dynamic-aperture, sextupole, electron	1188
	K. Soutome, T. Fujita, K. Fukami, K.K. Kaneki, C. Mitsuda, H. Ohkuma, M. Oishi, Y. Okayasu, S. Sasaki, J. Schimizu, Y. Shimosaki, M. Shoji, M. Takao, Y. Taniuchi, C. Zhang JASRI/SPring-8, Hyogo-ken, Japan M. Hasegawa, K. Kajimoto, T. Nakanishi SES, Hyogo-pref., Japan
	In the SPring-8 storage ring there are four magnet-free long straight sections (LSS) of about 30m. Recently we locally modified one of these sections by installing two quadrupole-triplets and divided it into three sub-sections. The vertical beta at the middle of each sub-section was lowered to 2.5m so that small gap in-vacuum undulators with a short period (min. gap: 5.2mm, period: 19mm) can be installed to build a high performance beamline for inelastic X-ray scattering. After modifying the lattice, however, the symmetry of the ring is lowered and, in general, it becomes difficult to keep sufficient dynamic aperture (DA) and momentum acceptance (MA). We solved this problem by combining the betatron phase matching, local chromaticity correction in LSS and cancellation of non-linear kicks due to sextupoles used for this correction. We could then recover DA and MA to almost the same level for the original one. The beam commissioning of the new lattice has successfully been finished, and from September 2011 it is used in user-operation. We will report our method of realizing a storage ring lattice having a very low symmetry and review the operation performance of the modified lattice.

TUPPC017	Orbit and Optics Correction to Realize Designed Machine Performance	optics, emittance, target, closed-orbit	1194
	Y. Seimiya, S. Kamada, A. Morita, K. Ohmi, K. Oide KEK, Ibaraki, Japan
	It is difficult for actual accelerators to achieve the designed machine performance without appropriate correction or adjustment of magnet errors. By correction as magnets are aligned to design orbit, we aim to be realized the designed machine performance. However, it is not easy to estimate the design orbit in real accelerators. In KEKB and PF, beam position monitor(BPM) can be calibrated to the center of quadrupole magnet(QM). BPM and QM misalignments (except rotation misalignment) referring to design orbit can be estimated using assumption that these misalignments are coincident. This is, design orbit at BPM and QM can be derived.

TUPPC020	A Scheme for Horizontal-vertical Coupling Correction at SuperKEKB	coupling, simulation, optics, target	1203
	H. Sugimoto, H. Koiso, A. Morita, Y. Ohnishi, K. Oide KEK, Ibaraki, Japan
	SuperKEKB is an 7 GeV electron and 4 GeV positron double ring collider project based on the nano beam scheme and is aimed to break the world's luminosity record. A horizontal flat beam is essential to realize the nano beam collisions. One of critical effect that induces unexpected coupling is machine error, such as magnet misalignment and field imperfection. Coupling correction, therefore, plays key role in the actual beam operation. In this study, we numerically explore a possible scheme for coupling correction in the SuperKEKB lattice. Some coupling measurement and correction methods are applied to the model lattice considering magnet misalignments and finite BPM resolution. Based on the results, the attainable smallest coupling in the actual SuperKEKB is discussed.

TUPPC025	Solaris Storage Ring Lattice Optimization with Strong Insertion Devices	optics, undulator, insertion, 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.

TUPPC027	Multi Objective Genetic Optimization for Linac Lattice of PAL XFEL	linac, electron, emittance, quadrupole	1224
	C.H. Yi, M.-H. Cho, S.H. Kim, W. Namkung POSTECH, Pohang, Kyungbuk, Republic of Korea H.-S. Kang PAL, Pohang, Kyungbuk, Republic of Korea K.-J. Kim ANL, Argonne, USA
	Funding: Work supported by MEST and POSTECH Physics BK21 Program. There are a large number of variables and objectives in design of XFEL linac lattices. Recently, most of accelerator physics field, are applying the multi-objective genetic algorithm (MOGA) for these kinds of problems. MOGA was applied to the PAL XFEL linac lattice design. Longitudinal position of all components was fixed before applying MOGA. RF parameters of RF cavities and bending angles of bunch compressors are selected as variables. Various beam parameters computed by ELEGANT were used as objectives. By using MOGA, new linac lattice designs with 2 and 3 bunch compressors was generated and their beam properties are presented in this paper.

TUPPC037	Update on LHeC Ring-Ring Optics	sextupole, insertion, optics, 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.

TUPPC041	A 3 TeV Muon Collider Lattice Design	quadrupole, emittance, dipole, collider	1254
	Y. Alexahin, E. Gianfelice-Wendt Fermilab, Batavia, USA
	Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy A new lattice for 3 TeV c.o.m. energy with β^=5mm was developed which follows the basic concept of the earlier 1.5 TeV design but uses quad triplets for the final focus in order to keep the maximum magnet strength and aperture about the same as in 1.5 TeV case. Another difference is employment of combined-function magnets with the goal to lower heat deposition in magnet cold mass and to eliminate regions without bending field which produce “hot spots” of neutrino radiation that can be an issue at higher energy. The proposed lattice is shown to satisfy the requirements on luminosity, dynamic aperture and momentum acceptance. * Y.Alexahin, E.Gianfelice-Wendt, A.Netepenko, Proc. IPAC10, Kyoto, May 2010, p. 1563

TUPPC043	Design of Accumulator and Compressor Rings for the Project-X Based Proton Driver	proton, linac, optics, synchrotron	1260
	Y. Alexahin, D.V. Neuffer Fermilab, Batavia, USA
	Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. A Muon Collider (MC) and Neutrino Factory (NF), which may be considered as a step towards MC, both require high-power (~4 MW) proton driver providing short (<1m) bunches for muon production. However, the driver repetition rate required for these two machines is different: ~15 Hz for MC and ~60 Hz for NF. This difference necessitates employing two separate rings: one for accumulation of the proton beam from the Project-X linac in a few (e.g., 4) long bunches, the other for bunch compression - one by one for NF or all at a time for MC with simultaneous delivery to the target. The lattice requirements for these two rings are different: the momentum compaction factor in the accumulator ring should be large (and possibly negative) to avoid the microwave instability, while the compressor ring can be nearly isochronous in order to limit the required RF voltage and reduce the dispersion contribution to the beam size. In the present report we consider ring lattice designs which achieve these goals.

TUPPC047	New Storage Ring Lattice for the Duke FEL Wiggler Switchyard System	wiggler, FEL, storage-ring, quadrupole	1272
	H. Hao, J.Y. Li, Y.K. Wu FEL/Duke University, Durham, North Carolina, USA
	Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. The Duke storage ring is a dedicated drive for the OK-4 FEL and OK-5 FEL, and for the state-of-the-art Compton gamma-ray source, High Intensity Gamma-Ray Source (HIGS). To produce FEL lasing below 190 nm and gamma-ray beams above 100 MeV, the FEL system needs to be upgraded by adding two helical OK-5 wigglers to increase the FEL gain with four OK5 wigglers for the VUV operation. To simultaneously preserve the linear polarization capability of the gamma-ray beam produced by the planar OK-4 FEL, a wiggler switchyard system is under development which will enable the switch between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight. In this work, we present the new magnetic lattice designed for the operation of the wiggler switchyard system. This new lattice is developed with great flexibility for the operation with different numbers of FEL wigglers, variable betatron tunes, and adjustable electron beam sizes at the collision point for the HIGS. In addition, the new lattice is developed for the operation in a wide range of energies, from 280 MeV to 1.2 GeV, with proper nonlinear dynamics compensations in order to realize a large dynamic aperture.

TUPPC048	Online Physics Model Platform	controls, EPICS, simulation, monitoring	1275
	P. Chu, Y. Zhang FRIB, East Lansing, Michigan, USA C. Benatti, V. Vuppala NSCL, East Lansing, Michigan, USA D. Dohan, G. Shen BNL, Upton, Long Island, New York, USA J. Wu SLAC, Menlo Park, California, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 For a complex accelerator such as the Facility for Rare Isotope Beams (FRIB), a transfer matrix based online model might not be sufficient for the entire machine. On the other hand, if introducing another modelling tools, physics applications have to be rewritten for all modelling tools. A platform which can host multiple modelling tools would be ideal for such scenario. Furthermore, the model platform along with infrastructure support can be used not only for online applications but also for offline purposes with multi-particle tracking simulation. In order to achieve such a platform, a set of common physics data structures has to be set. XAL's accelerator hierarchy based data structure is a good choice as the common structure for various models. Application Programming Interface (API) for physics applications should also be defined within a model data provider. A preliminary platform design and prototype is discussed.

TUPPC056	Optics Measurements and Corrections at RHIC	optics, quadrupole, proton, luminosity	1299
	M. Bai, J.N. Aronson, M. Blaskiewicz, Y. Luo, V.H. Ranjbar, G. Robert-Demolaize, S.M. White BNL, Upton, Long Island, New York, USA G. Vanbavinckhove CERN, Geneva, Switzerland
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The further improvement of RHIC luminosity performance requires more precise understanding of the RHIC modeling. Hence, it is necessary to minimize the beta-beat, deviation of measured beta function from the calculated beta functions based on an model. The correction of beta-beat also opens up the possibility of exploring operating RHIC polarized protons at a working point near integer, a preferred choice for both luminosity as well as beam polarization. The segment-by-segment technique for reducing beta-beat demonstrated in the LHC operation for reducing the beta-beat was first tested in RHIC during its polarized proton operation in 2011. It was then fully implemented during the RHIC polarized proton operation in 2012. This paper reports the commissioning results. Future plan is also presented.

TUPPC058	Beam Energy Variation with Dipole Fault	dipole, sextupole, closed-orbit, simulation	1305
	Y. Li, S. Krinsky BNL, Upton, Long Island, New York, USA
	Funding: Supported by Department of Energy Contract No. DE-AC02-98CH10886. The effect of dipole faults and closed orbit correction on the beam energy is studied both analytically and numerically using the ELEGANT code. Motivated by top-off safety analysis, we consider the case of single dipole faults and study how large an error can be compensated by the closed orbit correction system before the beam is lost.

TUPPC059	Extraction of the Lie Map from Realistic 3D Magnetic Field Map	dipole, quadrupole, extraction, dynamic-aperture	1308
	Y. Li BNL, Upton, Long Island, New York, USA X. Huang SLAC, Menlo Park, California, USA
	Funding: Supported by Department of Energy Contract No. DE-AC02-98CH10886. We present a method to extract the Lie map of any arbitrary accelerator magnet from its actual 3D field map. After fitting a Taylor map from multi-particle tracking trajectories through the actual field, we factorize the map into a Lie map using Dragt-Finn's method. This method is validated by comparing with COSY-infinity for a soft-edge quadrupole model. Applications of extracting symplectic maps for the SPEAR and NSLS-II dipoles are shown as examples. A comparison of the map-tracking results against the direct field-integration-based method also is given.

TUPPC070	Alternating Spin Aberration Electrostatic Lattice for EDM Ring	simulation, quadrupole, proton, storage-ring	1332
	Y. Senichev, R. Maier, D. Zyuzin FZJ, Jülich, Germany M. Berz MSU, East Lansing, Michigan, USA
	The idea of the electric dipole moment search using the storage ring (SrEDM) with polarized beam is realized under condition of the long-time spin coherency of all particles, the time during which the RMS spread of the spin orientation of all particles in the bunch reaches one radian. Following the requirements of the planned EDM experiment, the SCT should be more than 1000 seconds. During this time each particle performs about 10⁹ turns in the storage ring moving on different trajectories through the optics elements. At such conditions the spin-rotation aberrations associated with various types of space and time dependent nonlinearities start to play a crucial role. In this paper we consider a new method based on the alternating spin drift, causing it to rotate alternately, thereby limiting the growth of aberrations at one order of magnitude lower. As a result, using this method we can achieve the SCT of the order of 5000-6000 seconds. The difficulties of these studies are still in the fact that the aberrations growth observed in the scale of a 10⁹ turns. For the study we use an analytical method in composition with a numerical simulation by COSY Infinity.

TUPPC071	Comparison of Different Numerical Modelling Methods for Beam Dynamics in Electrostatic Rings	simulation, quadrupole, optics, proton	1335
	D. Zyuzin, R. Maier, Y. Senichev FZJ, Jülich, Germany S.N. Andrianov, A.N. Ivanov St. Petersburg State University, St. Petersburg, Russia M. Berz MSU, East Lansing, Michigan, USA
	To search the electric dipole moment was proposed to use polarized protons at the so-called "magic" momentum of 0.7 GeV/c in an electric storage ring. For studying beam dynamics in electrostatic rings different computational methods can be used. We used differential algebra methods realized in COSY Infinity and integrating program with symplectic Runge-Kutta methods. These methods were observed and compared for orbital and spin motion.

TUPPC072	Modeling of Matching Channel for Accelerator Complexes	controls, booster, quadrupole, dipole	1338
	E.A. Podzyvalov, S.N. Andrianov St. Petersburg State University, St. Petersburg, Russia D. Zyuzin FZJ, Jülich, Germany
	Practically modern accelerator facility can be considered as a composite machines. Therefore it is necessary to consider special matching channels to joint all accelerator components together. For such channels advance various requirements, which can be formulated in the form of criteria sets. In this paper considered a global optimization concept allows to find appropriate solutions sets. This approach is demonstrated on the problem of modeling the matching channels for NICA accelerator complex.

TUPPC073	Frequency Map Analysis for SuperB	resonance, dynamic-aperture, emittance, sextupole	1341
	S.M. Liuzzo, M.E. Biagini, P. Raimondi INFN/LNF, Frascati (Roma), Italy T. Demma LAL, Orsay, France Y. Papaphilippou CERN, Geneva, Switzerland
	The frequency map analysis is applied to the SuperB HER and LER lattices including the Final Focus, in order to understand the dynamic aperture limitation and provide insight for a working point optimization. In this respect, frequency and diffusion maps are evaluated applying random magnet misalignments and tilts, before and after correction of orbit, dispersion and coupling using Low Emittance Tuning techniques. The same analysis is performed for on and off momentum particles. The lattice properties are further investigated using working point scans and the correction of non linear resonance driving terms and amplitude detuning.

TUPPC079	Tracking LHC Models with Thick Lens Quadrupoles: Results and Comparisons with the Standard Thin Lens Tracking	quadrupole, simulation, optics, dipole	1356
	M. Giovannozzi, H. Burkhardt, T. Risselada CERN, Geneva, Switzerland
	So far, the massive numerical simulation studies of the LHC dynamic aperture were performed using thin lens models of the machine. This approach has the clear advantage of speed, but it has also the disadvantage of requiring re-matching of the optics from the real thick configuration to the thin one. Furthermore, as the figure-of-merit for the re-matching is the agreement between the beta-functions for the two model, while the quadrupole gradients are left free parameters, the effect of the magnetic multipoles might be affected by this approach and in turn the dynamic aperture computation. In this paper the new approach is described and the results for the dynamic aperture are compared with the old approach, including detailed considerations on the CPU-time requirements.

TUPPC080	Investigations of Scaling Laws of Dynamic Aperture with Time for Numerical Simulations including Weak-Strong Beam-Beam Effects	simulation, injection, dynamic-aperture, beam-beam-effects	1359
	M. Giovannozzi CERN, Geneva, Switzerland E. Laface ESS, Lund, Sweden
	A scaling law describing the time-dependence of the dynamic aperture, i.e., the region of phase space where stable motion occurs, was proposed in previous papers about ten years ago. It was shown that dynamic aperture has a logarithmic dependence on time, which would be suggested by some fundamental theorems of the theory of dynamical systems. So far, such a law was applied to single-particle effects only, i.e., the only source of non-linear effects was the magnetic imperfections. In this paper an attempt is made to extend the scaling law to the case of weak-strong beam-beam effects. The results of numerical simulations performed, including both non-linear magnetic imperfections and weak-strong beam-beam effects, are presented and discussed in detail.

TUPPC090	Beam Physics of Integrable Optics Test Accelerator at Fermilab	simulation, betatron, resonance, optics	1371
	A. Valishev, S. Nagaitsev Fermilab, Batavia, USA V.V. Danilov ORNL, Oak Ridge, Tennessee, USA D.N. Shatilov BINP SB RAS, Novosibirsk, Russia
	Funding: Fermi Research Alliance, LLC operates Fermilab under Contract DE-AC02-07CH11359 with the US Department of Energy. Fermilab's Integrable Optics Test Accelerator is an electron storage ring designed for testing advanced accelerator physics concepts, including implementation of nonlinear integrable beam optics and experiments on optical stochastic cooling. The machine is currently under construction at the Advanced Superconducting Test Accelerator facility. In this report we present the goals and the current status of the project, and describe the details of machine design. In particular, we concentrate on numerical simulations setting the requirements on the design and supporting the choice of machine parameters.

TUPPC100	On Quantum Integrable Systems	plasma, synchrotron, focusing, betatron	1392
	V.V. Danilov ORNL, Oak Ridge, Tennessee, USA S. Nagaitsev Fermilab, Batavia, USA
	Funding: This research is sponsored by Oak Ridge National Lab, under Contract No. DE-AC05-00OR22725, and Fermi National Lab, under Contract No. DE-AC02-07CH11359. Many quantum integrable systems are obtained using an accelerator physics technique known as Ermakov (or normalized variables) transformation. This technique was used to create classical nonlinear integrable lattices for accelerators and nonlinear integrable plasma traps. Now, all classical results are carried over to a nonrelativistic quantum case.

TUPPC102	Simulation Study of Beam-beam Effects in Ion Beams with Large Space Charge Tuneshift	space-charge, simulation, synchrotron, collider	1398
	C. Montag 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. During low-energy operations with gold-gold collisions at 3.85 GeV beam energy, significant beam lifetime reductions have been observed due to the beam-beam interaction in the presence of large space charge tuneshifts. These beam-beam tuneshift parameters were about an order of magnitude smaller than during regular high energy operations. To get a better understanding of this effect, simulations have been performed. Recent results are presented.

TUPPD003	Optimisation of Cooling Lattice Based on Bucked Coils for the Neutrino Factory	factory, emittance, simulation, cavity	1407
	A. Alekou, J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	The ionisation cooling technique will be used at the Neutrino Factory to reduce the transverse phase space of the muon beam. For efficient cooling, high average RF gradient and strong focusing are required to be applied in the cooling channel. However, high magnetic field at the position of the RF cavities induces electric field breakdown and therefore, a novel configuration, the Bucked Coils lattice, has been proposed to mitigate this problem. The Bucked Coils lattice has significantly lower magnetic field in the RF cavities by using coils of different radius and opposite polarity. This paper presents the optimisation of this lattice, its cooling performance, together with the preliminary conceptual engineering design.

TUPPP002	GLASS Study of the Canadian Light Source Storage Ring Lattice	dynamic-aperture, emittance, quadrupole, sextupole	1602
	W.A. Wurtz, L.O. Dallin CLS, Saskatoon, Saskatchewan, Canada
	GLASS is a technique for finding all potential operating points of a storage ring lattice by examining all possible configurations of the linear lattice. The Canadian Light Source (CLS) storage ring uses three quadrupole families, making it computationally efficient to use GLASS to study the lattice with unbroken symmetry. CLS does not employ harmonic sextupoles and has only two families of chromatic sextupoles. We can exhaust the sextupole degrees of freedom by requiring the horizontal and vertical chromaticities to be both zero. With no remaining free parameters in our lattice, it is possible to calculate dynamic aperture and momentum acceptance for select regions of interest uncovered by the GLASS scan. We find two regions with reasonable dynamic aperture and momentum acceptance: the region where we presently operate and a region that can be accessed by reversing the polarity of one quadrupole family.

TUPPP013	Effects of Multipoles in Dynamic Aperture of the ILSF Storage Ring	multipole, dynamic-aperture, sextupole, quadrupole	1632
	S. Fatehi, E. Ahmadi, F. Saeidi ILSF, Tehran, Iran D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain H. Ghasem IPM, Tehran, Iran
	Dynamic aperture of a synchrotron light source shrinks to small value due to the multipole errors caused by magnet design. In the ILSF storage ring, the tolerance of magnets has been taken into account in the simulation and sextupole magnets reoptimized to improve the dynamic aperture. This paper yields the evaluated dynamic aperture include of multipole errors.

TUPPP014	HiSOR-II, Compact Light Source with a Torus-knot Type Accumulator Ring	emittance, quadrupole, insertion, 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.

TUPPP015	Status and Recent Progress of SPring-8	coupling, emittance, storage-ring, optics	1638
	H. Ohkuma JASRI/SPring-8, Hyogo-ken, Japan
	The SPring-8 is an 8 GeV synchrotron radiation facility that has been in operation since 1997. The SPring-8 has been operated well and total user time has reached more than 53,700 hours, 75% of the total operation time. The average user time per year is about 4,000 hours. The average availability is about 98% in the past 15 years. The operational status and recent progress overview of SPring-8 is presented: the local lattice modification of 30-m long straight section for installing small gap (min. gap is 5.2 mm) in-vacuum undulators, the emittance coupling correction for the vertical beam size reduction, the test operation of low energy operation for the energy saving, and the study of lower emittance optics for the present SPring-8 storage ring. An outline of a future upgrade with a full-scale major lattice modification is also presented. We also present a little about recent progress of SPring-8 injecting accelerators.

TUPPP017	Lattice Design of the SSRF Storage Ring with Superbend	emittance, photon, dipole, optics	1644
	S.Q. Tian, B.C. Jiang, H.H. Li, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	The SSRF storage ring is being investigated by upgrading with normal conducting superbend of 3 T. The bending magnets are shortened, and thus some additional straight sections with the length of about 2 m are created in the center of the arc cell. They can be used to install more insertion devices. The lattice adjustment and the optics design are presented in this paper, where much efforts are made to maintain the effective emittance along the ring with respect to the nominal optics.

TUPPP018	Design and Commissioning of the Very Low Emittance Optics in the SSRF Storage Ring	emittance, optics, injection, storage-ring	1647
	S.Q. Tian, J. Chen, B.C. Jiang, Y.B. Leng, H.H. Li, L.Y. Yu, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	In synchrotron radiation light sources, there are continuous efforts to lower the storage ring emittance and thus increase its photon beam brightness. The lowest effective emittance of SSRF is found by a systematic method. Results of design and commissioning of this kind of optics are presented, of which the beam emittance is smaller than the nominal one by 1 nm.rad. The measured beam parameters agree well with the design ones.

TUPPP022	Beam Optics Measurements during ALBA Commissioning	quadrupole, optics, emittance, storage-ring	1656
	M. Muñoz, G. Benedetti, J. Campmany, D. Einfeld, 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. This paper reviews the results of the modeling of the lattice and the agreement with the LOCO measurement of the machine; the performance of the beta beating correction (critical in the ALBA case due to the large gradient in the bending magnet and the low number of quadrupole families), including effect of insertion devices; the lifetime measurement; tune scans; tune shift with horizontal amplitude; and the general agreement of the machine to the model using during the design. A brief summary of the modeling of the injector chain is included.

TUPPP024	Recent Progress on the MAX IV 1.5 GeV Storage Ring Lattice and Optics	storage-ring, dipole, vacuum, sextupole	1662
	S.C. Leemann MAX-lab, Lund, Sweden
	Construction of the MAX IV facility started in 2010 and commissioning is expected to begin in 2014. Once completed, 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 lattice and optics of the 1.5 GeV storage ring have been modified as a result of detailed magnet and vacuum system design. This paper discusses the lattice and optics changes as well as their effects.

TUPPP027	Subpicosecond Laser Slicing X-Ray Source for Time-resolved Research at TPS	wiggler, laser, emittance, photon	1671
	W.K. Lau, M.C. Chou, C.-S. Hwang, A.P. Lee, Y.-C. Liu, G.-H. Luo NSRRC, Hsinchu, Taiwan N.Y. Huang NTHU, Hsinchu, Taiwan
	The 3 GeV Taiwan Photon Source (TPS) under construction at NSRRC should be ready for user run in 2014. X-ray users in many research areas will then be benefited. However, there has been a growing interest in ultrafast time-resolved research in the island. The feasibility of using ultrafast laser for electron-beam slicing at TPS to produce sub-picosecond x-ray pulses is being investigated recently. The design and layout of a laser slicing scheme with W250 wiggler as the energy modulator in a 7 m medium straight section and EPU48 and IU22 radiators in other straight sections will be presented. It will offer the unique opportunity to gain experience in experimental techniques needed for FEL science.

TUPPP034	BPM Gains and Beta Function Measurement Using MIA and FPGA BPMs at the APS	betatron, optics, quadrupole, feedback	1686
	C.-X. Wang, G. Decker, H. Shang, C. Yao ANL, Argonne, USA D. Ji IHEP, Beijing, People's Republic of China
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The broadband BPM system at the Advanced Photon Source (APS) is being upgraded with FPGA-based beam history modules, which fix problems in the old history modules and increase functionality. Using these new turn-by-turn BPMs and the newly developed real-time feedback system, measurement of BPM gains, beta function and other optics functions are being developed based on model-independent analysis of turn-by-turn data and model fitting, aiming at quasi-real-time and high-accuracy optics measurement. We will discuss our effort, especially experience with strong nonlinearity and wakefields typical of 3rd-generation light sources.

TUPPP037	Status of the ALS Brightness Upgrade	brightness, insertion, 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.

TUPPP039	Vertical Dispersion Bump Design for Femto-second Slicing Beamline at the ALS	coupling, quadrupole, emittance, radiation	1698
	C. Sun, C. Steier, W. Wan LBNL, Berkeley, California, USA
	Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Femto-second (fs) slicing beamline has been brought to the operation at the Advanced Light Source (ALS) since 2002. It employs the resonant interaction of an electron bunch with a fs laser beam in a wiggler to energy-modulate a short section of the bunch. The induced energy modulation is then converted to a transverse displacement using a vertical dispersion bump downstream of the wiggler. Thus, the radiation from the fs pulse can be separated from the main bunch radiation. The current dispersion bump design has proved to be an effective and reliable one. However, the ALS storage ring lattice is under an upgrade to improve its brightness. After the completion of the upgrade, a new low emittance will be implemented, and the current dispersion bump design needs to be modified to provide the adequate vertical displacement, while minimizing the vertical emittance and spurious dispersion. In this paper, we present the new design of a vertical dispersion bump using Multi-Objective Genetic Algorithm (MOGA) for the ALS upgrade lattice.

TUPPP062	Start to End Simulation of Three Bunch Compressor Lattice for PAL XFEL	FEL, emittance, linac, simulation	1738
	H.-S. Kang, M.-H. Cho, J.H. Han, T.-H. Kang, I.S. Ko PAL, Pohang, Kyungbuk, Republic of Korea C.H. Yi POSTECH, Pohang, Kyungbuk, Republic of Korea
	The PAL XFEL is a 0.1-nm hard X-ray FEL project starting from 2011 to finish in 2014, which aims at achieving higher photon flux than 10¹² photons/pulse at 0.1 nm using a 10 GeV electron linac. The PAL XFEL is designed to have a hard x-ray undulator line at the end of linac and a branch line at 2.65 GeV point for soft X-ray undulator line. The three bunch compressor lattice (3-BC) is chosen to minimize emitance growth due to CSR and minimize correlated energy spread. The 3-BC lattice makes it possible to operate soft X-ray FEL undulator line simultaneously and independently from hard X-ray FEL undulator line.

TUPPP069	A Compact, Modular Electron Beam Delay Line for Use in Novel Free-Electron Laser Schemes	undulator, quadrupole, FEL, electron	1759
	J.K. Jones, J.A. Clarke, N. Thompson STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Two Free-Electron Laser (FEL) schemes have been proposed, for the generation of attosecond pulse trains* and for the improvement of the longitudinal coherence of SASE FELs*, in which repeated electron delays are implemented within the undulator lattice. To obtain the maximum performance and flexibility from these schemes it is advantageous to use an electron delay line that satisfies the isochronicity conditions, as well as being compact, modular and, ideally, variable. In this paper we present initial designs for such a system, along with simulations of its performance. We investigate both in-undulator and out-of-undulator designs, and compare the applicability of each for various aspects of the FEL design, as well as commenting on the mechanical and magnetic implications of the schemes. N.R. Thompson and B.W.J. McNeil. Phys. Rev. Lett. 100, 203901 (2008). ** N.R. Thompson, D.J. Dunning and B.W.J. McNeil, IPAC2010, TUPE050, p. 2257 (2010).

TUPPR003	The Design of Spin-Rotator with a Possibility of Helicity Switching for Polarized Positron at the ILC	positron, solenoid, damping, polarization	1813
	L.I. Malysheva, O.S. Adeyemi, V.S. Kovalenko, G.A. Moortgat-Pick, A. Ushakov University of Hamburg, Hamburg, Germany A.F. Hartin, B. List, N.J. Walker DESY, Hamburg, Germany S. Riemann, F. Staufenbiel DESY Zeuthen, Zeuthen, Germany
	Funding: Work supported by German Federal Ministry of education and research. Joint Research project R&D Accelerator Spin Management, contract N 05H10CUE At the ILC, positrons are produced with longitudinal polarization at the source. In order to preserve the polarization, the spin must be rotated into the vertical direction prior to injection into the damping rings. A new design of the spin rotator is presented that allows to randomly switch between the two vertical orientations between successive bunch trains. After rotating the spin back to longitudinal polarization, this corresponds to a choice between the two possible helicity states at the interaction point. The fast flipping is achieved by inserting two parallel spin rotation sections with opposite polarities, with a fast magnet that allows to choose between the sections.

TUPPR008	One 233 km Tunnel for Three Rings: e⁺e^-, p-pbar, and μ⁺+μ⁻	collider, dipole, emittance, luminosity	1828
	G.T. Lyons, L.M. Cremaldi, A. Datta, M. Duraisamy, T.H. Luo, D.J. Summers UMiss, University, Mississippi, USA
	Funding: Supported by DE-FG05-91ER40622 In 2001, a cost analysis was conducted to build a 233 km circumference tunnel in northern Illinois for a Very Large Hadron Collider (VLHC). Here we outline the implementations of e⁺e⁻, proton anti-proton, and μ⁺+ μ⁻ collider rings in such a tunnel using recent technological innovations. The 500 GeV e⁺e⁻ collider employs a Crab Waist Crossing, ultra low emittance damped bunches, a vertical IP focal length of 0.06 cm, 12 GV of superconducting RF, and 0.026 Tesla low coercivity, grain oriented silicon steel/concrete dipoles. The 40 TeV proton anti-proton collider uses the high intensity Fermilab anti-proton source, exploits high cross sections for proton anti-proton production of high mass states, and uses 2 Tesla 0.005% ultra low carbon steel/YBCO superconductor magnets run with liquid neon. The 40 TeV muon ring ramps the 2 Tesla superconducting magnets at 8 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 2 to 20 TeV in 72 orbits with 72% survival, and mitigates neutrino radiation with a phase shifting, roller coaster FODO lattice.* * G. T. Lyons, http://arxiv.org/pdf/1112.1105

TUPPR013	Design Integration and Vision Sharing for the ILC	linear-collider, linac, collider, damping	1837
	B. List, L. Hagge, S. Sühl, N.J. Walker, N. Welle DESY, Hamburg, Germany
	The Global Design Effort for the International Linear Collider is currently preparing the Technical Design Report, which will be released in early 2013. The starting point of a consistent and correct design is the accelerator lattice, which defines the layout of the machine. Integrating the lattice geometrically and optically provides the basis for civil engineering and conventional facilities planning and finally the cost estimate. Tools that provide three-dimensional visualization of the lattice and tunnel help to perform the design integration and allow sharing a common vision of the final accelerator. We will present the process that was established to arrive at such an integrated design and the tools that were developed to support that process by analyzing and visualizing lattice files.

TUPPR022	Traditional Final Focus System for CLIC	luminosity, collider, linear-collider, quadrupole	1858
	H. Garcia, A. Latina, R. Tomás CERN, Geneva, Switzerland H. Garcia UPC, Barcelona, Spain
	Next generation linear colliders needs a very strong focalisation to reach nanometer beam size at the Interaction Point. This task and the chromatic correction generated by the strong lenses is done by the Final Focus System. A traditional Final Focus System based on dedicated chromaticity correction sections is presented as an alternative for CLIC Final Focus. The scheme of the lattice is shown and some tolerances in the Final Doublet are calculated. A systematic tuning using Simplex algorithm and sextupole knobs is performed. The complete comparison to the Local Chromaticity correction scheme is presented.

TUPPR031	Experimental Verification of the CLIC Decelerator with theTest Beam Line in the CLIC Test Facility 3	extraction, quadrupole, alignment, linac	1885
	R.L. Lillestøl, S. Döbert, M. Olvegård, A. Rabiller, G. Sterbini CERN, Geneva, Switzerland E. Adli University of Oslo, Oslo, Norway
	The Test Beam Line in the CLIC Test Facility 3 is the first prototype of the CLIC drive beam decelerator. The main purpose of the experiment is to demonstrate efficient 12 GHz rf power production and stable transport of an electron drive beam during deceleration. The Test Beam Line consists of a FODO structure with high precision BPMs and quadrupoles mounted on mechanical movers for precise beam alignment. Nine out of the planned 16 Power Extraction and Transfer Structures have currently been installed and commissioned. We correlate rf power production measurements with the drive beam deceleration measurements, and compare the two measurements to the theoretical predictions. We also discuss the impact of the drive beam bunch length and bunch combination on the measurements.

TUPPR035	A Comparative Study for the CLIC Drive Beam Decelerator Optics	optics, quadrupole, injection, alignment	1897
	G. Sterbini, D. Schulte CERN, Geneva, Switzerland E. Adli University of Oslo, Oslo, Norway
	The baseline for the CLIC drive beam decelerators optics consists of a 2-m-long FODO cell. This solution was adopted to have strong focusing in order to mitigate the effect of the PETS wakefields and to minimize the drive beam envelope. Taking into account the most recent PETS design, we compare the performance of the baseline FODO cell with a proposal that consider twice longer FODO cell. Despite of the expected cost in term of performance, the reduction of the complexity of the system due to the halving of the number of quadrupoles can be beneficial for the overall optimization of the decelerator design.

TUPPR041	Update on ILC Positron Source Start-to-End Simulation	positron, electron, undulator, linac	1909
	W. Liu, W. Gai ANL, Argonne, USA
	As a result of the changes in the new ILC base line, there are many changes in the positron source beamline layouts and thus a new lattice design is required. According to the changes in the ILC baseline, a new lattice design for the ILC positron source has been developed at ANL. In this paper, both the new ILC positron source beamline lattice and the corresponding start to end simulation results are presented.

TUPPR060	Detection of Ground Motion Effects on the Beam Trajectory at ATF2	ground-motion, quadrupole, extraction, linear-collider	1954
	Y. Renier, J. Pfingstner, D. Schulte, R. Tomás CERN, Geneva, Switzerland
	The ATF2 experiment is currently demonstrating the feasibility of the beam delivery system for the future linear collider. The tunning is very critical to obtain the nanometer vertical beam size at the interaction point and in the case of CLIC, ground motion effects on the beam must be corrected. In this respect, as a proof of principle of a ground motion feed forward, the ground motion effects on the beam trajectory are extracted from the beam position monitor readings.

TUPPR063	Investigation into Electron Cloud Effects in the ILC Damping Ring Design	photon, vacuum, wiggler, electron	1963
	J.A. Crittenden, J.V. Conway, G. Dugan, M.A. Palmer, D. L. Rubin CLASSE, Ithaca, New York, USA L.E. Boon, K.C. Harkay ANL, Argonne, USA M.A. Furman LBNL, Berkeley, California, USA S. Guiducci INFN/LNF, Frascati (Roma), Italy M.T.F. Pivi, L. Wang SLAC, Menlo Park, California, USA
	Funding: Work supported by the U.S. Department of Energy DE-SC0006506 We report modeling results for electron cloud buildup in the ILC damping ring lattice design. Updated optics, wiggler magnet, and vacuum chamber designs have recently been developed for the 5-GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effect of photon scattering on the interior of the vacuum chamber. Operational implications of the resulting electron cloud buildup will be discussed.

TUPPR065	Wiggler Magnet Design Development for the ILC Damping Rings	wiggler, damping, vacuum, linear-collider	1969
	J.A. Crittenden, M.A. Palmer, D. L. Rubin CLASSE, Ithaca, New York, USA
	Funding: Work supported by the U.S. Department of Energy DE-SC0006506. The baseline damping ring lattice design for the International Linear Collider employs nearly 60 2.2-m-long superconducting wiggler magnets to provide the damping necessary to achieve the specified horizontal emittance. We describe the OPERA-based finite-element model developed for the 14-pole, 30-cm period, 7.62-cm gap superferric design which meets the 2.1 T peak field requirement. Transfer functions and field uniformity results are discussed. We present results for the accuracy of the optimized analytic model needed for symplectic tracking algorithms, as well as implications for the updated engineering design.

TUPPR066	Characterization of Single Particle Dynamics for the International Linear Collider Damping Ring Lattice	damping, emittance, wiggler, multipole	1972
	J.P. Shanks, J.A. Crittenden, M.A. Palmer CLASSE, Ithaca, New York, USA D.L. Rubin Cornell University, Ithaca, New York, USA
	Funding: DOE Award DE-SC0006506 The baseline design for the International Linear Collider damping rings is a 3.2 km circumference racetrack, with 5 GeV beam energy. The transverse damping time is 26 ms and the normalized horizontal emittance 5 mm-mrad. Nearly 60 2.2-m-long superconducting wigglers per ring increase the radiation damping rate by an order of magnitude and reduce horizontal emittance by a factor of 5. We characterize the sensitivity to magnet misalignments and field errors, and establish the minimum numbers of corrector magnets and beam position monitors required for tuning vertical emittance to less than 20 nm-rad. We validate the specified tolerable guide field multipole errors consistent with adequate dynamic aperture. Tune scans are used to identify stable working points. In tracking studies we use a wiggler model based on fits to 3-dimensional field maps.

TUPPR070	High-Gradient Photonic Band-gap (PBG) Structure Breakdown Testing at Ku-Band	diagnostics, HOM, damping, coupling	1984
	B.J. Munroe, A.M. Cook, M.A. Shapiro, R.J. Temkin MIT/PSFC, Cambridge, Massachusetts, USA
	Photonic Band-gap (PBG) structures continue to be a promising area of research forfuture accelerator structures. Previous experiments at X-Band have demonstrated that PBG structures can operate at high gradient and low breakdown probability, provided that pulsed heating is controlled. Two single-cell standing-wave structures have been constructed at MIT to investigate breakdown performance of PBG structures. A metallic structure with small rods will be used to test performance with very high surface temperature rise, while an over-moded structure with dielectric rods will investigate alternative solutions to the issue of surface temperature rise. Both structures are expected to reach gradients of at least 100 MV/m and will utilize novel diagnostics, including fast camera imaging and optical spectroscopy of breakdowns.

TUPPR071	Experimental High-Gradient Testing of an Elliptical-Rod Photonic Band-Gap (PBG) Structure at X-Band	damping, wakefield, klystron, HOM	1987
	B.J. Munroe, M.A. Shapiro, R.J. Temkin MIT/PSFC, Cambridge, Massachusetts, USA V.A. Dolgashev, S.G. Tantawi, A.D. Yeremian SLAC, Menlo Park, California, USA R.A. Marsh LLNL, Livermore, California, USA
	An 11.4 GHz Photonic Band-gap (PBG) structure where the rods in the inner row have an elliptical cross-section has been designed at MIT and tested at high power and high repetition rate at SLAC. This structure exhibits lower surface magnetic fields on the rods relative to previous round-rod PBG structures tested at SLAC, which reduces the ohmic heating of the rod surface in an effort to reduce pulsed heating damage. This improved PBG structure was tested experimentally such as to avoid excessively high breakdown rates and surface temperature rise. The structure demonstrated performance comparable to disc-loaded waveguide (DLWG) structures with the same iris geometry, achieving greater than 100 MV/m gradient at a breakdown probability of less than 10-3 per pulse per m for 150 ns pulses. This level of performance demonstrates that elliptical-rod PBG structures could be candidates for future accelerator applications.

TUPPR085	Recycler Chromaticities and End Shims for NOvA at Fermilab	sextupole, quadrupole, dynamic-aperture, dipole	2023
	M. Xiao Fermilab, Batavia, USA
	In era of NOvA operation, it is planned to slip-stack six on six Booster proton batches in the Recycler ring for a total intensity of 5×10¹³ protons/cycle. During the slip-stacking, the chromaticities are required to be jumped from (-2,-2) to (-20,-20). However, they can only be adjusted to (-12,-12) from (-2,-2) using existing 2 families of powered sextupoles. On the other hand, the presently designed Recycler lattice for Nova replaces the 30 straight section with 8 “D-D half FODO cells”. We use 3 quads in a half-cell to obtain the working point under the limit of the feasible quad strength, and the maximum beta-function in this section cannot be less than 80 m. In this paper, we re-designed the end shims of the permanent magnets in the ring lattice with appropriate quadrupole and sextupole components to meet both chromaticity and tune requirements. We are able to use 2 quads in a half cell in RR30 straight section within feasible quad strength. The maximum beta-functions are also lowered to around 55 m. The dynamic aperture tracking has been done using MAD to simulate the scenario of beam injection into the Recycler ring for Nova.

WEPPD020	Vacuum System for TPS Booster	vacuum, booster, ion, electron	2540
	C.M. Cheng, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh NSRRC, Hsinchu, Taiwan
	The TPS booster is designed for lower beam emittance and 3GeV full energy injection ramped up from 150MeV. It is a synchrotron accelerator of 496.8m in circumference and located concentric with the electron storage ring in the same tunnel. The vacuum system for the booster is divided into six super periods and each has nine bending magnet chambers. The beam duct is made of thin stainless steel tube extruded to the elliptical cross section with inner diameters of 35 mm×20 mm and thickness of 0.7 mm. All the chambers will be supported on the inner wall of the tunnel. The straightness of the extruded thin chambers is controlled within 2.5 mm in 4 m length. The bending chamber is made by mechanical bending from the straight tube. All the beam ducts will be chemical cleaned prior to welding, with flanges or BPM chambers, to form the long chambers in the clean room before installation. The arrangement of vacuum pumps are distributed to fulfill an average pressure of ＜1×10^-6 Pa. The detailed design and the construction status will be described in the paper.

WEPPD066	Design of a Stripline Kicker for Tune Measurement in CSNS RCS	kicker, impedance, cyclotron, wakefield	2675
	X.Y. Yang, S. Fu, T.G. Xu IHEP, Beijing, People's Republic of China
	For CSNS RCS tune measurement, tune value is measured by exciting the bunch with strip-line kicker fed with white noise and using FFT algorithm to the turn-by-turn position of the bunch in the BPM. This article simulates the strip-line kicker in RCS and the efficiency of the kicker is discussed in the MATLAB environment. The parameters of the kicker with arc electrode structure such as wake impedance, thermal state and VSWR are analyzed based on the advantage of this design.

WEPPP026	Dielectric-plate-implanted Higher Order Mode (HOM) Waveguide for High Intensity Multi-beam Device Application	HOM, simulation, wakefield, electron	2781
	Y.-M. Shin Fermilab, Batavia, USA
	A mode-selective oversized RF-beam channel has been investigated for high intensity multi-beam devices. Implanting the equi-spaced dielectric plates at the transverse positions where longitudinal electric fields of a HOM are minimal in the micro-metallic structure strongly suppresses all lower energy modes and other wakefield modes. The dielectric lattice captures only a single HOM of the wavelengths that correspond to the plate spacing. Electromagnetic simulations have shown that the lower energy modes, TE10 and TE20 modes, are suppressed down to < ~ -60 dB by two plate loads, while TE310-mode prominently propagates through the 2 mm long waveguide only with 4 dB (= -2dB/mm) at 1 THz. The numerical calculation indicated that the TE30 mode has ~ a few times higher Q than the lower energy modes. The strong single mode selectivity has been extensively looked into with a more highly overmoded structure. Feasibility analysis of the HOM structure for multi-beam device application is under investigation. Particle-in-cell (PIC) simulation has shown coherent beam bunching and energy gain from THz driving signal.

WEPPP027	PBG-slab Embedded Traveling Wave Structure for Planar Beam Accelerator Application	electron, HOM, acceleration, photon	2784
	Y.-M. Shin Fermilab, Batavia, USA
	The oversized traveling wave (TE10-mode) channel integrated with the photonic-band-gap (PBG) slab arrays have been investigated for planar beam accelerator application. Simulation analysis showed that the slab arrays allow only the PBG-modes (5-6 GHz) to propagate with ~ 2 dB of insertion loss, corresponding to ~ 1.14 dB/cm attenuation, which thereby effectively suppresses trapped non-PBG modes down to ~ -14.3 dB/cm. It will enable monochromatic propagation of fundamental acceleration modes along the heavily over-moded planar waveguide without anomalous excitation of unstable trapped HOMs. The saturated maximum field gradients of the accelerating structure have been analyzed with respect to operational frequency bands corresponding to structural sizes. The field gradient of the guided PBG-mode has been investigated with finite-integral-method (FIM) simulations at W-band. This mode-filter could be utilized for HOM dampers in high aspect ratio (HAR) planar beam accelerators. An experimental test is currently under consideration.

WEPPR004	Effect of Beam-beam Interactions on Stability of Coherent Oscillations in a Muon Collider	collider, luminosity, resonance, quadrupole	2940
	K. Ohmi KEK, Ibaraki, Japan Y. Alexahin Fermilab, Batavia, USA
	In order to achieve the peak luminosity of a muon collider in the 10³⁵ cm^-2 s^-1 range the number of muons per bunch should be of the order of a few units of 10¹² rendering the beam-beam parameter as high as 0.1 per IP. Such strong beam-beam interaction can be a source of instability if the working point is chosen close to a coherent beam-beam resonance. On the other hand, the beam-beam tune spread can provide a mechanism of suppression of the beam-wall driven instabilities. In this report the coherent instabilities driven by beam-beam and beam-wall interactions are studied with the help of BBSS code for the case of 1.5 TeV c.o.m muon collider.

WEPPR012	Simulating High-Intensity Proton Beams in Nonlinear Lattices with PyORBIT	space-charge, resonance, simulation, proton	2961
	S.D. Webb, D.T. Abell, D.L. Bruhwiler, J.R. Cary Tech-X, Boulder, Colorado, USA V.V. Danilov, A.P. Shishlo ORNL, Oak Ridge, Tennessee, USA S. Nagaitsev, A. Valishev Fermilab, Batavia, USA
	High-intensity proton linacs and storage rings are essential for a) state-of-the-art neutron source user facilities, b) extending the high-energy physics intensity frontier, c) as a driver to generate pions for a future neutrino factory or muon collider, and d) for transmutation of radioactive waste and associated energy production. For example, Project X at Fermilab will deliver MW proton beams at energies ranging from 3 to 120 GeV. Nonlinear magnetic lattices with large tune spreads and with integrable, nearly integrable* and chaotic* dynamics have been proposed to maximize dynamic aperture and minimize particle loss. We present PyORBIT*** simulations of proton dynamics in such lattices, including the effects of transverse space charge. * V. Danilov and S. Nagaitsev, PR ST-AB 13 084002 (2010) K. Sonnad and J. Cary, Phys. Rev. E 69 056501 (2004) * A. Shishlo, J. Holmes and T. Gorlov, From Proceedings of IPAC '09 351-354

WEPPR013	Design of an Electrostatic Extraction Section for the University of Maryland Electron Ring	extraction, simulation, emittance, electron	2964
	K.J. Ruisard Rutgers University, The State University of New Jersey, Piscataway, New Jersey, USA B.L. Beaudoin, I. Haber, R.A. Kishek, T.W. Koeth UMD, College Park, Maryland, USA
	Funding: This work is supported by the US Dept. of Energy Office of High Energy Physics. The University of Maryland Electron Ring (UMER) is a 11.5 meter circumference, 10 keV, electron storage ring dedicated to the study of the physics space-charge-dominated beams transported over long path lengths. The intensity of the space charge in UMER can be varied by aperturing the injected beam current from 0.6 mA to 100 mA. Recently, the electron beam has been transported over one thousand turns. To fully characterize the transverse and longitudinal evolution of the beam on a turn-by-turn basis, extraction and transport to a diagnostic station is required. We present the design of a pulsed electric extraction system that satisfies the challenging constraint of fitting the hardware within the dense magnet lattice. The extraction system must universally accommodate the range beam intensities and minimize any disruption to the circulating beam

WEPPR015	Intrabeam Scattering Studies at CesrTA	emittance, scattering, electron, positron	2970
	M. P. Ehrlichman Cornell University, Ithaca, New York, USA F. Antoniou, Y. Papaphilippou CERN, Geneva, Switzerland W. Hartung, M.A. Palmer, D.P. Peterson, N.T. Rider, D. L. Rubin, J.P. Shanks, C.R. Strohman, S. Wang CLASSE, Ithaca, New York, USA R. Holtzapple CalPoly, San Luis Obispo, California, USA
	Funding: NSF Award (PHY-0734867) NSF Award (PHY-1002467) Japan/US Cooperation Program Education and lifelong learning, co-financed by Greece and the European Union Intrabeam scattering dilutes the emittance of low energy, low emittance rings. Because CesrTA can be operated at low energies with low transverse emittances and high bunch intensity, it is an ideal laboratory for the study of IBS effects. Furthermore, CesrTA is instrumented for accurate beam size measurements in all three dimensions, providing the possibility of a complete determination of the intensity dependence of emittances. Models based on classical IBS theories and multi-particle simulations are used to estimate the effect of IBS at CesrTA at different beam emittances, intensities and energies. The first measurements from machine studies at CesrTA are presented.

WEPPR039	Nonlinear Lattice for Space-Charge Dominated Beam Transport with Suppressed Emittance Growth	quadrupole, focusing, space-charge, emittance	3021
	Y.K. Batygin, A. Scheinker LANL, Los Alamos, New Mexico, USA
	We present a feasible design for the implementation of a beam emittance growth suppressing lattice for space-charge dominated beams. Our analysis is based on original derivations developed in . We present a FODO focusing channel with quadrupole and duodecapole components which on average create the ﬁeld required to match the high-brightness beam with the structure. Matched beam exhibits smaller emittance growth than that in regular quadrupole focusing channel. Numerical results demonstrate the lattice’s performance in preventing halo formation of a nonuniform space charge dominated beam. Y. Batygin, Phys. Rev. E, 57, 5, p. 6020 (1998).

WEPPR092	Beam Ion Instability in ILC Damping Ring with Multi-gas Species	ion, vacuum, damping, simulation	3150
	L. Wang, M.T.F. Pivi SLAC, Menlo Park, California, USA
	Ion induced beam instability is one critical issue for the electron damping ring of the International Linear Collider (ILC) due to its ultra small emittance of 2 pm. The beam ion instability with various beam filling patterns for the latest lattice DTC02 is studied using code IONCLOUD. The code has been benchmarked with SPEAR3 experimental data and there is a good agreement between the simulation and observations. It uses the optics from MAD and can handle arbitrary beam filling pattern and vacuum. Different from previous studies, multi-gas species have been used simultaneously in the simulation. This feature makes it more accurate.

THXB03	Beam and Spin Dynamics in an Electric Proton EDM Ring	proton, dipole, storage-ring, quadrupole	3203
	R.M. Talman CLASSE, Ithaca, New York, USA J. Talman BNL, Upton, Long Island, New York, USA
	Electric dipole moment (EDM) measurements may help to answer the question ‘‘Why is there more matter than anti-matter in the present universe?'' For a charged baryon like the proton such a measurement is thinkable only in a ring in which a bunch of protons is stored for more than a few minutes, with polarization ‘‘frozen'' (relative to the beam velocity) and with polarization not attenuated by decoherence. Beam and spin dynamics in an all-electric lattice with these characteristics is described. Rings for other charged baryons, such as deuterons or helium-3 nuclei, are also possible but, requiring both electric and magnetic fields, they are more complicated.
	Slides THXB03 [0.155 MB]

THPPC039	Study of RF Breakdown in Normal Conducting Cryogenic Structure	cryogenics, impedance, klystron, accelerating-gradient	3368
	V.A. Dolgashev, J.R. Lewandowski, D.W. Martin, S.G. Tantawi, S.P. Weathersby, A.D. Yeremian SLAC, Menlo Park, California, USA
	Funding: *Work supported by DoE, Contract No. DE-AC02-76SF00515. RF Breakdown experiments on short accelerating structures at SLAC have shown that properties of rf breakdown probability are reproducible for structures of the same geometry. At a given rf power and pulse shape, the rf breakdown triggers continuously and independently at a constant average rate. Hypotheses describing the properties of the rf breakdown probabilities involve defects of metal crystal lattices that move under forces caused by rf electric and magnetic fields. The dynamics of the crystal defects depend on the temperature of the structure. To study the dependence we designed and built an experimental setup that includes a cryogenically cooled single-cell, standing-wave accelerating structure. This cavity will be high power tested at the SLAC Accelerator Structure Test Area (ASTA).

THPPD010	Design, Assembly and First Measurements of a Short Model for CLIC Final Focus Hybrid Quadrupole QD0	quadrupole, multipole, magnet-design, permanent-magnet	3515
	M. Modena, O. Dunkel, J.G. Perez, C. Petrone, P.A. Thonet, D. Tommasini CERN, Geneva, Switzerland E. Solodko, A.S. Vorozhtsov JINR, Dubna, Moscow Region, Russia
	In the framework of the Compact Linear Collider (CLIC) R&D, a tunable hybrid magnet design has been proposed for the final focus QD0 quadrupole. A short model of the magnet has been realized in order to validate the novel design and its expected performances. In order to achieve extremely high quadrupole gradients (>500 T/m), the magnet design combines: a core structure made in magnetic CoFe alloy “Permendur”, permanent magnet blocks, and air-cooled electromagnetic coils. Relevant aspects of this design are the wide tunability of the gradient range, the compactness and the absence of any vibrations. In this paper a reminder of the magnet design concept is given; then, the procurement and assembly main aspects are presented, followed by the results of the magnetic measurements. Finally, some manufacturing considerations relative to a full size magnet procurement are discussed.

THPPD036	High-Field Combined-Function Magnets for a 1.5×1.5 TeV Muon Collider Storage Ring	dipole, quadrupole, collider, magnet-design	3587
	V. Kashikhin, Y. Alexahin, N.V. Mokhov, A.V. Zlobin Fermilab, Batavia, USA
	Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy A new storage ring lattice based on combined function high-field magnets and conceptual designs of superconducting magnets with dipole and quadrupole coils for a muon collider with a c.o.m. energy of 3 TeV and an average luminosity of 4x10³⁴ cm^-2 s^-1 are presented. Magnets are designed to provide the required focusing field gradient and bending field in the aperture with the appropriate operation margin. Magnets have large apertures to provide an adequate space for internal absorbers, vacuum insulation, beam pipe, and helium channel. Coil cross-sections were optimized to achieve the best possible field quality in the magnet aperture occupied with beams. Magnet parameters are reported and compared with the requirements. Energy deposition calculations with the MARS code have allowed to optimize parameters of inner absorbers and collimators in interconnect regions, thus reducing peak power density and dynamic loads to the tolerable levels.

THPPD054	Low Current Bipolar Magnet Power Supply System at the PLS-II Storage Ring	dipole, quadrupole, EPICS, power-supply	3635
	S.-C. Kim, J.Y. Huang, K.R. Kim, S.H. Nam, S. Shin, Y.G. Son, C.W. Sung PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: * This work is supported by the Ministry of Education, Science and Technology, Korea. Lattice of the Storage Ring (SR) is changed from TDB to DBA, and beam energy is enhanced from 2.5 GeV to 3.0 GeV at the Pohang Light Source upgrade (PLS-II). At the PLS-II, Magnet Power Supplies (MPS) were newly designed according to magnet specification of the PLS-II. All MPSs are adopted switching type power conversion technology. Low current bipolar MPSs for vertical corrector(VC), horizontal corrector(HC), fast corrector(FC), aux.-quadrupole(AQ), skew(SK) and dipole trim coil(TR) magnets are H-bridge type. All MPSs are performed less than ± 10 ppm output current stability and adopted full digital controller. Except vertical corrector MPSs, all unipolar and bipolar MPSs are developed as embedded EPICS IOC. In this paper, we report on the development and characteristics of the bipolar MPS for the PLS-II Storage Ring.

THPPD055	High Current Unipolar Magnet Power Supply System at the PLS-II Storage Ring	power-supply, quadrupole, sextupole, septum	3638
	S.-C. Kim, J.Y. Huang, K.R. Kim, S.H. Nam, S. Shin, Y.G. Son, C.W. Sung PAL, Pohang, Kyungbuk, Republic of Korea
	Funding: This work is supported by the Ministry of Education, Science and Technology, Korea. Lattice of the Storage Ring (SR) is changed from TDB to DBA, and beam energy is enhanced from 2.5 GeV to 3.0 GeV at the Pohang Light Source upgrade (PLS-II). At the PLS-II, Magnet Power Supplies (MPS) were newly designed according to magnet specification of the PLS-II. All MPSs are adopted switching type power conversion technology. High current unipolar MPSs for bending(BD), main-quadrupole(MQ), sextupole(ST) and septum(SP) magnet are parallel operation type of unit stack buck type power supply. Unit stack of unipolar MPS has capability maximum 250A and operation 10kHz. BD and MQ MPS are adopted four stack as each stack 90degree phase shift switching, and have capability maximum 1000 A. ST MPS is adopted two stack as each stack 180degree phase shift switching, and have capability maximum 500 A. SP MPS is adopted single, and have capability maximum 250 A. All unipolar MPSs are developed as full digital controller, embedded EPICS IOC and operated less than ± 10ppm current stability. In this paper, we report on the development and characteristics of the high current unipolar MPS for the PLS-II SR.

THPPP005	Space Charge Effect in the Presence of x-y Coupling in J-PARC MR	coupling, space-charge, emittance, simulation	3731
	K. Ohmi KEK, Ibaraki, Japan S. Hatakeyama JAEA/J-PARC, Tokai-mura, Japan
	It is crucial issue to suppress beam loss due to space charge force in J-PARC MR. We focus x-y coupling as a source of the beam loss. x-y coupling is measured by turn-by-turn beam position monitors in J-PARC MR. A space charge simulation under the measured x-y coupling evaluates the beam loss. Tolerance of x-y coupling and how to improve the beam loss are discussed.

THPPP024	Alignment and Aperture Scan at the Fermilab Booster	booster, injection, alignment, proton	3785
	K. Seiya, J.R. Lackey, W.L. Marsh, W. Pellico, D.A. Still, A.K. Triplett, A.M. Waller Fermilab, Batavia, USA
	The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour, which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be the source of issues. The booster accelerates beam from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the beam is lost within 3 msec after the injection. The aperture at injection energy was measured and compared with the survey data. The magnets are going to be realigned in March 2012 in order to increase the aperture. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves will be discussed in this paper.

THPPP056	Beam Loss Due to Misalignments, RF Jitter and Mismatch in the Fermilab Project-X 3GeV CW Linac	linac, solenoid, quadrupole, beam-losses	3868
	J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, B.G. Shteynas, N. Solyak Fermilab, Batavia, USA
	This paper presents an analysis of beam losses along the current design of the FNAL 3 GeV superconducting cw linac. Simulations from the RFQ exit up to the end of the linac (~430 meters) are performed on the FermiGrid using the beam dynamics code TRACK. The impact of beam mismatch, element misalignments, and RF jitter on the beam dynamics is discussed and corresponding beam loss patterns are presented. A correction scheme to compensate for misalignments is described.

THPPP091	Status of the Project-X CW Linac Design	linac, cryomodule, emittance, rfq	3948
	J.-F. Ostiguy, P. Berrutti, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Superconducting CW linac was proposed for Project X to accelerate H⁻ beam from 2.1 MeV to 3 GeV with nominal peak and average currents of respectively 5 mA and 1 mA. Linac built of 5 different families of resonators: half-wave, spoke (2), and elliptical (2) working at 162.5 MHz 325 MHz and 650 MHz to cover all energy range. Cavities and focusing elements are assembled in cryomodules. In baseline design all cryomodules are separated by short warm sections. It makes machine more reliable and maintainable and provide space for beam diagnostics and collimation. A long (~10m) gap between cryomodules at1 GeV is also being considered to provide space for beam extraction for nuclear experimental program. In paper we present the latest lattice of the linac baseline design and results of beam studies for this lattice. We briefly compare performance of the baseline design with alternative one without half-wave resonator section.

THPPR013	Beam Transport in Alternative Lattices at the University of Maryland Electron Ring (UMER)	quadrupole, injection, focusing, betatron	3993
	S. Bernal, B.L. Beaudoin, M. Cornacchia, R.A. Kishek, D.F. Sutter UMD, College Park, Maryland, USA
	Funding: This work is funded by the US Dept. of Energy Offices of High Energy Physics and High Energy Density Physics, and by the US Dept. of Defense Office of Naval Research and Joint Technology Office. We discuss the motivation, general procedure and results of first experiments of beam transport with two alternative focusing schemes at UMER, a low-energy (10 keV), high-current (1-100 mA) electron storage ring. The new ring optics simplifies injection and RMS envelope matching, and gives us a larger number of beam position monitors (BPMs) per (un-depressed) betatron wavelength, all of which are desirable conditions for better orbit control. Furthermore, one of the new optics schemes is more symmetrical than the standard one, facilitating e.g. the implementation of quadrupole scans for betatron resonance studies. The alternative lattices also allow us to expand significantly on the tune parameter space available for the study of space-charge dominated beam transport.

THPPR018	Development Progress of NSLS-II Accelerator Physics High Level Applications	controls, linac, alignment, EPICS	4005
	L. Yang, J. Choi, Y. Hidaka, G. Shen, G.M. Wang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the Department of Energy. The High Level Applications (HLA) for NSLS-II commissioning is a development in progress. It is in a client-server framework and uses Python programming language for scripting and graphical user interface application development. This new development provides both scripting and graphical user interface (GUI) controls. The services developed in controls group provide name server, archiving, machine snapshot etc. The clients are developed mainly in the physics group and have measurement, analysis and modeling capabilities.

THPPR053	A CW FFAG for Proton Computed Tomography	cyclotron, proton, extraction, acceleration	4094
	C. Johnstone, D.V. Neuffer Fermilab, Batavia, USA H.L. Owen STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom P. Snopok IIT, Chicago, Illinois, USA
	Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy An advantage of the cyclotron in proton therapy is the continuous (CW) beam output which reduces complexity and response time in the dosimetry requirements and beam controls. A CW accelerator requires isochronous particle orbits at all energies through the acceleration cycle and present compact isochronous cyclotrons for proton therapy reach only 250 MeV (kinetic energy) which is required for patient treatment, but low for full Proton Computed Tomography (PCT) capability. PCT specifications need 300-330 MeV in order for protons to transit the human body. Recent innovations in nonscaling FFAG design have achieved isochronous performance in a compact (~3 m radius) design at these higher energies. Preliminary isochronous designs are presented here. Lower energy beams can be efficiently extracted for patient treatment without changes to the acceleration cycle and magnet currents.

THPPR063	1 GeV CW Nonscaling FFAG for ADS, and Magnet Parameters	extraction, cyclotron, simulation, proton	4118
	F. Méot, W.-T. Weng BNL, Upton, Long Island, New York, USA C. Johnstone Fermilab, Batavia, USA P. Snopok Illinois Institute of Technology, Chicago, IL, USA
	Multi-MW proton driver capability remains a challenging, critical technology for many core HEP programs, particularly the neutrino ones such as the Muon Collider and Neutrino factory, and for next generation energy applications such as Accelerator Driven Subcritical Reactors (ADS) and Accelerator Transmutation of Waste for nuclear power and waste management. Work is focused almost exclusively on an SRF linac, as, to date, no re-circulating accelerator can attain the 10^-20 MW capability necessary for the nuclear applications. Recently, the concept of isochronous orbits has been explored and developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. The FFAG can remain isochronous beyond the energy reach of cyclotrons and with fixed magnetic fields and strong focusing coupled to recent advances in tune stability, dynamic aperture, and footprint, serious study is underway on a potential application to the ADS problem. Work is progressing on a stable, high intensity, 0.25-1GeV isochronous FFAG. Development and studies of novel magnets with the nonlinear radial fields required to support isochronous operation are reported here.

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MOOAB03

FACET First Beam Commissioning

linac, emittance, damping, sextupole

46

G. Yocky, C.I. Clarke, W.S. Colocho, F.-J. Decker, M.J. Hogan, N. Lipkowitz, J. Nelson, P.M. Schuh, J.T. Seeman, J. Sheppard, H. Smith, T.J. Smith, M. Stanek, Y. Sun, J.L. Turner, M.-H. Wang, S.P. Weathersby, G.R. White, U. Wienands, M. Woodley
SLAC, Menlo Park, California, USA

Funding: Work supported by U.S. Department of Energy, Contract DE-AC02-76SF00515.
The FACET (Facility for Advanced aCcelerator Experimental Tests) facility at SLAC has been under Construction since summer 2010. Its goal is to produce ultrashort and transversely small bunches of very high intensity (20kA peak current) to facilitate advanced acceleration experiments like PWFA and DLA. In June of 2011 the first electron beam was brought into the newly constructed bunch-compression chicane. Commissioning work included restarting the linac and damping ring, verifying hardware, establishing a good beam trajectory, verifying the optics of the chicane, commissioning diagnostic devices for transverse and longitudinal bunch size, and tuning up the beam size and bunch compression. Running a high-intensity beam through the linac without BNS damping and with large energy spread is a significant challenge. Optical aberrations as well as wakefields conspire to increase beam emittance and the bunch compression is quite sensitive to details of the beam energy and orbit, not unlike what will be encountered in a linear-collider final-focusing system. In this paper we outline the steps we took while commissioning as well as the challenges encountered and how they were overcome.

Slides MOOAB03 [9.167 MB]

MOEPPB003

Status of the PRISM FFAG Design for the Next Generation Muon-to-Electron Conversion Experiment

solenoid, target, injection, proton

79

J. Pasternak, A. Alekou, M. Aslaninejad, R. Chudzinski, L.J. Jenner, A. Kurup, Y. Shi, Y. Uchida
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
R. Appleby, H.L. Owen
UMAN, Manchester, United Kingdom
R.J. Barlow
University of Huddersfield, Huddersfield, United Kingdom
K.M. Hock, B.D. Muratori
Cockcroft Institute, Warrington, Cheshire, United Kingdom
D.J. Kelliher, S. Machida, C.R. Prior
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
Y. Kuno, A. Sato
Osaka University, Osaka, Japan
J.-B. Lagrange, Y. Mori
Kyoto University, Research Reactor Institute, Osaka, Japan
M. Lancaster
UCL, London, United Kingdom
C. Ohmori
KEK, Tokai, Ibaraki, Japan
T. Planche
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
S.L. Smith
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
H. Witte
BNL, Upton, Long Island, New York, USA
T. Yokoi
JAI, Oxford, United Kingdom

The PRISM Task Force continues to study high intensity and high quality muon beams needed for next generation lepton flavor violation experiments. In the PRISM case such beams have been proposed to be produced by sending a short proton pulse to a pion production target, capturing the pions and performing RF phase rotation on the resulting muon beam in an FFAG ring. This paper summarizes the current status of the PRISM design obtained by the Task Force. In particular various designs for the PRISM FFAG ring are discussed and their performance compared to the baseline one, the injection/extraction systems and matching to the solenoid channels upstream and downstream of the FFAG ring are presented. The feasibility of the construction of the PRISM system is discussed.

MOPPC008

LHC Optics Determination with Proton Tracks Measured in the Roman Pots Detectors of the TOTEM Experiment

proton, optics, scattering, coupling

136

H. Niewiadomski, H. Burkhardt
CERN, Geneva, Switzerland
F.J. Nemes
KFKI, Budapest, Hungary

The TOTEM experiment at the LHC is equipped with near beam movable devices – called Roman Pots (RP) – which detect protons scattered at the interaction point (IP) arrived to the detectors through the magnet lattice of the LHC. Proton kinematics at IP is reconstructed from positions and angles measured by the RP detectors, on the basis of the optical functions between IP and the RP locations. The precision of optics determination is therefore of the key importance for the experiment. TOTEM developed a novel method of machine optics determination making use of angle-position distributions of elastically scattered protons observed in the RP detectors. The method has been successfully applied to the data samples registered in 2010 and 2011. The studies have shown that the transport matrix could be estimated with a precision better than 1%.

MOPPC013

Optics and Lattice Optimizations for the LHC Upgrade Project

optics, luminosity, ion, insertion

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.

MOPPC020

Field Tolerances for the Triplet Quadrupoles of the LHC High Luminosity Lattice

quadrupole, multipole, dynamic-aperture, target

169

Y. Jiao, Y. Cai, Y. Nosochkov, M.-H. Wang
SLAC, Menlo Park, California, USA
R. De Maria, S.D. Fartoukh, M. Giovannozzi, E. McIntosh
CERN, Geneva, Switzerland

Funding: This work is supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
It has been proposed to implement an Achromatic Telescopic Squeezing (ATS) scheme* in the high luminosity LHC lattice to reduce the beta functions at the Interaction Points (IP) up to a factor of 8. As a consequence, the nominal 4.5-km peak beta functions reached in the inner triplets at collision will be increased by the same factor. This therefore justifies the installation of new, larger aperture superconducting triplet quadrupoles. These higher beta functions will enhance the effects of the triplet quadrupole field errors leading to smaller beam dynamic aperture. To maintain the acceptable dynamic aperture, the effects of the triplet multipole field errors must be re-evaluated, thus specifying new tolerances. Such a study has been performed for the so-called “4444” collision optics of the ATS scheme, where the IP beta functions are reduced by a factor of 4 in both planes with respect to a pre-squeezed value of 60 cm at two collision points. The dynamic aperture calculations were performed using SixTrack. The impact on the triplets’ field quality is studied and presented in details.
* S. Fartoukh, “An Achromatic Telescopic Squeezing (ATS) Scheme for LHC Upgrade”, Proc. of IPAC11, p. 2088 (2011).

MOPPC022

Off-momentum Dynamic Aperture for Lattices in the RHIC Heavy Ion Runs

luminosity, ion, heavy-ion, emittance

175

Y. Luo, M. Bai, M. Blaskiewicz, W. Fischer, X. Gu, A. Marusic, T. Roser, S. Tepikian, S.Y. Zhang
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 this article we calculate and compare the off-momentum dynamic aperture for lattices with different phase advances per FODO cell in the RHIC heavy ion runs. A lattice with an increased phase advance was adopted in 2008-2011 to reduce transverse emittance growth rates from intra-beam scattering. However, during these runs, a large beam loss was observed with longitudinal RF re-bucketing which increased the momentum spread. With operational transverse stochastic cooling in the 2011 RHIC heavy ion run, the transverse intra-beam scattering emittance growth was eliminated, and the beam loss during stores was determined by the off-momentum aperture and burn-off from luminosity. We investigate the possibilities to increase the off-momentum dynamic aperture that would lead to an increase in the integrated luminosity.

MOPPC026

Simulations of Coherent Beam-Beam Effects with Head-on Compensation

electron, resonance, proton, simulation

187

S.M. White, W. Fischer, Y. Luo
BNL, Upton, Long Island, New York, USA

Funding: Work partially supported by Brookhaven Science Associates, LARP, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Electron lenses are foreseen to be installed in RHIC in order to mitigate the head-on beam-beam effects. This would allow operation with higher bunch intensity and result in a significant increase in luminosity. We report on recent strong-strong simulations that were carried out using the RHIC upgrade parameters to assess the impact of coherent beam-beam effects in the presence of head-on compensation.

MOPPC029

Off-momentum Beat-beat Correction in the RHIC Proton Run

sextupole, quadrupole, simulation, proton

196

Y. Luo, M. Bai, W. Fischer, A. Marusic, K. Mernick, 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 this article we will present the measurement and correction of the off-momentum β^*-beat in the RHIC proton run. The beta-beat will be measured with the AC dipole and by shifting RF frequency. We will focus on the correction of the off-momentum beta-beat at the interaction points IP6 and IP8 with the arc chromatic sextupole families. The effects of the off-momentum beta-beat correction on the global chromaticities and dynamic aperture will be estimated through beam experiments and the numerical simulation.

MOPPC030

Status of the Decay Ring Design for the IDS Neutrino Factory

injection, kicker, insertion, 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)

MOPPC049

Status of the Non-scaling Fixed Field Alternating Gradient Ring Design for the International Design Study of the Neutrino Factory

factory, acceleration, septum, electron

241

J.S. Berg, H. Witte
BNL, Upton, Long Island, New York, USA
M. Aslaninejad, J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
N. Bliss, A.J. Moss
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
S.M. Pattalwar
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The International Design Study of the Neutrino Factory is working towards delivering the optimized design of the neutrino factory facility to be presented in the Reference Design Report (RDR) in 2013. In the current baseline design a linear non-scaling fixed field alternating gradient accelerator (FFAG) was chosen as an efficient solution for the final muon acceleration. We describe updates to the design since our previous report*. We report on beam dynamics studies on the lattice. We describe recent work on the engineering for the lattice, and the results of a recent first pass at a cost estimate for the machine. Finally, we describe how an FFAG may be applicable to a lower energy neutrino factory in light of recent experimental results regarding the value of the theta(13) neutrino mixing angle**.
* J. S. Berg et al., in Proceedings of IPAC2011, San Sebastian, Spain, 832.
** F. P. An et al., Phys. Rev. Lett. 10⁸, 171803 (2012); J. K. Ahn et al., arXiv:1204.0626v2 [hep-ex] (2012).

MOPPC050

The International Design Study for the Neutrino Factory

factory, target, proton, acceleration

244

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

A neutrino factory is a facility for producing a large neutrino flux from the decay of high energy muons. The International Design Study for the Neutrino Factory (IDS-NF) aims to produce a reference design report for such a facility. The report will contain the physics motivation for the facility, describe the accelerator and detector, and estimate the cost for the facility. We will briefly discuss the physics capabilities for a neutrino factory, including how recent neutrino physics results affect our understanding of a neutrino factory's performance and advantages. We will give an overview of our baseline design for the accelerator facility. We will then outline the most significant areas of progress in our studies of the accelerator subsystems.
Paper submitted on behalf of the International Design Study for the Neutrino Factory collaboration.

MOPPC053

Modeling of Bending Magnets for SIRIUS

dipole, simulation, multipole, sextupole

250

X.R. Resende, R. Basílio, L. Liu, P.P. Sanchez, G. Tosin
LNLS, Campinas, Brazil

The new Brazilian synchrotron source, Sirius, will be a 3 GeV storage ring with a triple bend lattice with a minimum emittance of 1.7 nm rad. The ring dipoles are excited with permanent magnets. The middle bend has a small 1.4 degree slice in its center with 1.94 T field and serve as an additional hard X-ray source with critical energy of 11.6 keV. Other bending magnets have low 0.50 T field with gradients, allowing for a further emittance reduction. The bending slice shows a longitudinal profile with no uniform field plateau and with long-range fringe fields which are coupled with the fields of neighbouring dipoles. To take into account the interaction of the field-intersecting dipoles, realistic 3D models of the magnets have been created and their field configuration solved using finite element techniques. Field maps calculated from the 3D magnet models were used for the construction of segmented models of bend elements in beam dynamics codes.

MOPPC063

Computation of the 2D Transverse Wake Function of an Electron Cloud for Different Parameters

electron, simulation, dipole, wakefield

280

A. Markoviḱ, G. Pöplau, U. van Rienen
Rostock University, Faculty of Computer Science and Electrical Engineering, Rostock, Germany

Funding: Work supported by DFG under contract number RI 814/20-2.
A PIC simulation of the interaction of a positive charged bunch with an e-cloud yields the wake kick from the electrons on the tail particles of the bunch. The wake is induced from a certain offset in the transverse position of the head parts of the bunch which perturb the electron distribution. Such a pre-computed wake functions of each offset part of the bunch are forming a matrix which could be used for investigating single bunch stability under several assumptions. In this paper we investigate the linear scalability of the kick with the offset value. Furthermore we investigate the wake values for different realistic electron densities. Another important parameter for realizing the single bunch stability simulation is the optimal number of bunch slices in longitudinal direction. Here we study the thickness of the slices in conjunction with the mobility of the electrons around the beam axis.

MOPPC076

New Features of the Parallel TRACY for Nonlinear Beam Dynamics

dynamic-aperture, sextupole, closed-orbit, betatron

310

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

The TRACY code is used to analyze and simulate the nonlinear beam dynamics of the designed lattice. To speed up the lattice design flow, we parallelized the TRACY by MPI and developed a GUI by GTK+ to integrate the functions of TRACY and added a function of nonlinear optimization adapted from OPA, which is used to optimize the nonlinear driving terms by powell algorithm. The GUI is used for parameter input and data visualization. The procedures of nonlinear optimization and beam dynamics analysis are integrated and streamlined. Users do not need to write and compile the code any more. The results will be demonstrated in this report.

MOPPC077

Simulation and Analysis of the Beam Signal in Taiwan Photon Source Booster

booster, betatron, multipole, synchrotron

313

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

The TPS (Taiwan Photon Source) booster is a combined function FODO lattice with six super-periods; the total circumference is 496.8 m. To prepare the analysis tools for beam commissioning, we simulate the TPS booster turn-by-turn BPM data with two programs, MAD-X PTC and Tracy-2.6, which are for both DC (constant beam energy) and AC (beam energy in regular ramping) modes. We analyze the simulation data with MIA (Model Independent Analysis) and ICA (Independent Component Analysis), in order to reconstruct beam parameters like beta function, phase advance, dispersion, etc. We include multipole errors, alignment errors, BPM noises or other noises in simulation, and try to design a good strategy for real data analysis.

MOPPC078

Simulation Studies of Injection Scheme in TPS Storage Ring

injection, simulation, storage-ring, alignment

316

Y.C. Lee, H.-P. Chang, P.J. Chou
NSRRC, Hsinchu, Taiwan

Funding: NSRRC, Hsinchu, Taiwan.
The baseline lattice of TPS storage ring was finalized in October 2009. Later upon users’ request, we plan to implement the double mini-βy lattice in three 12-m straight sections of TPS storage ring. These locations were chosen to maintain the symmetry of the storage ring lattice. Particle tracking for the first few turns were used to check the injection scheme of storage ring, including errors introduced in manufacturing and installation process. Results of simulation studies will be presented.

MOPPC080

Modeling Space Charge in an FFAG with Zgoubi

space-charge, emittance, acceleration, synchrotron

322

S.C. Tygier, R. Appleby, H.L. Owen
UMAN, Manchester, United Kingdom
R.J. Barlow
University of Huddersfield, Huddersfield, United Kingdom

The Zgoubi particle tracker uses a ray tracing algorithm that can accurately track particles with large offset from any reference momentum and trajectory, making it suitable for FFAGs. In high current FFAGs, for example an ADSR driver, space charge has a significant effect on the beam. A transverse space charge model was added to Zgoubi using the interface pyZgoubi. The magnets are sliced and a space charge kick is applied between each slice. Results are presented for an ADSR driver lattice.

MOPPC083

LinguaFranca - A Graphical User Interface for Accelerator Modeling

simulation, quadrupole, optics, collider

331

T.J. Roberts
Muons, Inc, Batavia, USA

This is a proposed project to develop an innovative Graphical User Interface that permits users to construct, explore, optimize, and evaluate accelerator systems efficiently and effectively. While it will be designed with students in mind, accelerator physicists will also find it useful in dealing with the plethora of modeling tools and their different languages. The internal representation of the system is specifically designed to be useable as a text-based description of the system, and to make it easy for users to interface it to essentially any accelerator-modeling tool, regardless of its description language. Many accelerator designers have expressed frustration with the current “Tower of Babel” among modeling programs, and this project will address that directly. In particular, this will make it straightforward to use fast but less realistic programs to design and optimize a system, and then use slower but more realistic programs to evaluate its performance. Graphical interfaces are emphasized, making it easy to construct the system graphically, display the system and its beam, and use on-screen controls to vary parameters and observe their effects immediately.

MOPPC086

Accelerator Simulation - Beyond High Performance Computing

target, simulation, site, emittance

340

S. James, G.M. Jung, B.C. Li, K. Muriki, H. Nishimura, Y. Qin, K. Song, C. Sun
LBNL, Berkeley, California, USA

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Accelerator modeling and simulation studies heavily rely on High Performance Computing (HPC). Public Cloud computing has opened a new service horizon for HPC by offering an on-demand, Virtual Private Cloud (VPC). Previously, we investigated using Amazon HPC public Cloud for lattice optimization applications and evaluated performance*. In this research, we use the Amazon VPC technology to extend local HPC resources to provide a seamless, hybrid, and secure environment when the demand for computing capacity spikes.
* C. Sun et al., "HPC Cloud Applied to Lattice Optimization," Proc. PAC2011, New York, WEP151, p. 1767 (2011).

MOPPC095

XAL's Online Model at ReA3 to Understand Beam Performance

linac, simulation, cavity, cryomodule

358

C. Benatti
NSCL, East Lansing, Michigan, USA
P. Chu, M.J. Syphers, X. Wu
FRIB, East Lansing, Michigan, USA

Funding: This material is based on work supported by the National Science Foundation under Grant No. PHY-1102511 and by Michigan State University.
The ReA3 facility at the NSCL at MSU has been designed to reaccelerate rare isotope beams to 3MeV/u. ReA3 consists of a charge to mass selection section, a normal conducting RFQ, a superconducting linac, and transport beam lines that deliver the beam to the experiments. The beam optics designs were developed using COSY and IMPACT. A code with an online model capable of interacting with the control system, such as XAL, developed at SNS, would be ideal for studying this system*. New elements have been added to XAL’s already extensive list of supported devices in order to model elements unique to the NSCL. The benchmarking process has been completed for establishing the use of XAL’s Online Model at the NSCL, and preliminary results from its use at the ReA3 control room have been obtained. The development of applications to fit the needs of the program is ongoing. A summary of the benchmarking process is presented including both transverse and longitudinal studies.
* J. Galambos et al., Proc. PAC 2005, p. 79, (2005); doi: 10.1109/PAC.2005.1590365.

MOPPD002

Ultra-low Energy Storage Ring at FLAIR

extraction, antiproton, storage-ring, ion

367

C.P. Welsch, D. Newton, M.R.F. Siggel-King
Cockcroft Institute, Warrington, Cheshire, United Kingdom
O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov
MPI-K, Heidelberg, Germany
J. Harasimowicz, M. Putignano, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged.
The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 10⁶ were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.

MOPPD019

Vertical Orbit Excursion FFAG Accelerators with Edge Focussing

proton, injection, neutron, dynamic-aperture

406

S.J. Brooks
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

FFAGs with vertical orbit excursion (VFFAGs) provide a promising alternative design for the magnets in fixed-field machines. They have a vertical magnetic field component that increases with height in the vertical aperture, yielding a skew quadrupole focussing structure. The end fields of such magnets with edge angles provide an alternating gradient without the need for reverse bends, thus reducing the machine circumference. Similarly to spiral scaling horizontal FFAGs (but unlike non-scaling versions), the machine has fixed tunes and no intrinsic limitation on momentum range. Rings capable of boosting the 150mm.mrad geometric emittance beam from the ISIS proton synchrotron to 3, 5 and 12GeV using superconducting magnets are presented, the latter corresponding to 2.5MW beam power.

MOPPD020

A Model for a High-Power Scaling FFAG Ring

injection, dynamic-aperture, extraction, proton

409

G.H. Rees, D.J. Kelliher, S. Machida, C.R. Prior, S.L. Sheehy
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

High-power FFAG rings are under study to serve as drivers for neutron spallation, muon production, and accelerator-driven reactor systems. In this paper, which follows on from earlier work*, a 20 - 70 MeV model for a high-power FFAG driver is described. This model would serve as a test bed to study topics such as space charge and injection in such rings. The design incorporates a long straight to facilitate H^- charge exchange injection. The dynamic aperture is calculated in order to optimize the working point in tune space. The injection scheme is also described. A separate design for an ISIS injector, featuring a novel modification to the scaling law, was also studied.
*G.H. Rees and D.J. Kelliher, “New, high power, scaling, FFAG driver ring designs” HB2010, Morschach, September 2010, MOPD07, p. 54, http://www. JACoW.org

MOPPP010

Investigation of CSR Effect for Femtosecond Electron Bunches in an Isochronous Accumulator Ring

simulation, radiation, electron, linac

589

N.Y. Huang, H. Hama, F. Hinode, S. Kashiwagi, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan

Coherent synchrotron radiation (CSR) from a novel isochronous ring is a candidate for light source that provides THz radiation with high average flux. A compact isochronous accumulator ring (IAR) for the maximum beam energy of 54 MeV has been designed so as to eliminate the 0th order momentum compaction factor, and the 1st order of it is mostly compensated. In addition, the path length deviation due to betatron motion is mostly compensated in a cell. Though there is no RF cavity in IAR, the injected beam may circulate for certain number of turns. Multi experimental stations can be allocated like synchrotron radiation facilities. However, it has been well known that instability due to the CSR wake field is an issue for the beam stability in the ring operated at low alpha mode. Therefore, a study for effects of the CSR wake on the bunch length and shape in IAR has been in progress. It has turned out that the maximum longitudinal field strength created by CSR would be ~ 0.15 MV/m for the case of 100 fs Gaussian bunch, which is considerably an intense field. To protect the bunch shape from the CSR wake, further study is definitely required.

MOPPP057

Optimization of the Low-emittance Lattice of the APS Booster Synchrotron

booster, emittance, injection, sextupole

690

C. Yao, V. Sajaev, N. Sereno, H. Shang
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06- CH11357.
The APS booster is a 7GeV electron synchrotron. Three lattices have been originally designed with a nominal beam emittance of 132, 109, and 92 nm, respectively. In the past we have mostly operated the booster with the 132 nm lattice because of its better stability. The lower-emittance lattices are not utilized. In early 2010 we upgraded the booster ramp correction and reduced the 360Hz current ripples of the ramp supplies. Current ramp errors have been significantly reduced. This raises our interest in running the low- emittance lattice to improve APS storage ring injection efficiency and reduce radiation losses. This report presents the optimization methods and measurement results of booster beam performance of the booster 92nm lattice.

MOPPP058

Improvements to the APS Booster Injection Controllaw Process

injection, controls, booster, synchrotron

693

C. Yao, F. Lenkszus, H. Shang, S. Xu
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06- CH11357.
The APS booster is a 7-GeV electron synchrotron with a 0.5-second cycle time. The booster runs a set of injection control programs that corrects the injection beam trajectory based on the beam history of two BPMs. An IOC process calculates the I and Q components of beam oscillation from turn-by turn beam position samples over the first 64 turns. The booster injection control programs apply phase, energy, and transverse angle correction based on the result of the IOC processing. The initial system was installed in 2007. Since installation the system has mostly worked well for normal user operations. However, occasionally the system has yielded inconsistent results. Recently we reviewed the signal and processes involved in this system and made necessary upgrades to some components, including selection of a new set of two input BPMs, optimization of FFT parameters, and addition of an injection tune control program. These upgrades have significantly improved the effectiveness and consistency of the system. We report the findings, analysis, and results.

MOPPP060

Top-Off Mode of Operations: Setting Limits on the Extracted Beam Energy by Constraining Currents of Multiple Booster Dipole Power Supplies.

dipole, booster, extraction, injection

696

T.V. Shaftan
BNL, Upton, Long Island, New York, USA

In preparation for top-off mode of the NSLS-II operations we have studied impact of errors in the dipole power supply current on the extracted beam energy, which has to be interlocked so to satisfy the safety requirements. The NSLS-II booster dipole circuits are combined into 3 independent PS circuits, which adds complexity to the analysis of the extracted beam energy limits.

MOPPP064

Challenges of Quasiperiodic APPLE Undulators

undulator, polarization, synchrotron, synchrotron-radiation

705

J. Bahrdt
HZB, Berlin, Germany
S. Sasaki
HSRC, Higashi-Hiroshima, Japan

APPLE undulators have become workhorses in many synchrotron radiation facilities for the production of variably polarized light. In helical mode higher harmonics are not produced. In linear mode (horizontal, vertical, inclined) higher harmonics may contaminate the first harmonic and spoil the quality of experimental data. Planar undulators employing a quasiperiodic magnetic structure have been built and they are successfully operated at several places. The implementation of a quasiperiodic lattice in an APPLE undulator is more complicated since the device is operated in various modes of operation. The proposed APS-upgrade includes a quasiperiodic APPLE undulator which is intended to be operated in the range 2.4-27 keV. A detailed analysis of the magnetic and spectral performance of this device is presented.

MOPPR001

Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring

storage-ring, electron, polarization, synchrotron

771

K.P. Wootton, R.P. Rassool
The University of Melbourne, Melbourne, Australia
M.J. Boland, Y.E. Tan
ASCo, Clayton, Victoria, Australia
W.J. Corbett, M.H. Donald, X. Huang, R.R. Ortiz, J.A. Safranek, K. Tian
SLAC, Menlo Park, California, USA

Accurate electron beam energy measurements are valuable for precision lattice modelling of high-brightness light sources. At SPEAR3 the beam energy was measured using the resonant spin depolarisation method with striplines to resonantly excite the spin tune and a sensitive NaI scintillator beam loss monitor was used to detect resulting changes in Touschek lifetime. Using the combined apparatus an electron beam energy of 2.997251(7) GeV was measured, giving a relative uncertainty better than 3x10^-6. The measured momentum compaction factor was found to be in close agreement with the numerical model value using rectangular defocussing gradient dipoles with measured magnetic field map profiles. In this paper we outline the chosen experimental technique, with emphasis on its applicability to electron storage rings in general.

MOPPR036

Correlation Analysis of Beam Diagnostic Measurements in SSRF

status, diagnostics, feedback, background

858

Z.C. Chen, Y.B. Leng, Y.B. Yan
SSRF, Shanghai, People's Republic of China
B.P. Wang
SINAP, Shanghai, People's Republic of China

Funding: Supported by National Natural Science Foundation of China (11075198)
Signals from various probes of the beam diagnostic system in Shanghai Synchrotron Radiation Facility (SSRF) were processed with correlation analysis algorithms. The resulting data allowed us to sort the probes by confidence, which means the stable and accurate signals could be separated from the faulty or noisy ones. And the beam dynamics measurements became electronic instrument free at the same time. This makes it possible to eliminate bad Beam Position Monitors (BPM) from the feedback system, offer a more confident set of beam parameters and estimate useful global information by extracting the relationship between some probes.

MOPPR079

Horizontal Beam-size Measurements at CESR-TA Using Synchrotron-light Interferometer

emittance, synchrotron, synchrotron-radiation, scattering

972

S. Wang, J.V. Conway, D.L. Hartill, M.A. Palmer, D. L. Rubin
CLASSE, Ithaca, New York, USA
R.F. Campbell, R. Holtzapple
CalPoly, San Luis Obispo, California, USA

Funding: DOE Award DE-FC02-08ER41538 NSF Award (PHY-0734867) NSF Award (PHY-1002467) NSF Award (PHY-1068662).
A horizontal beam profile monitor utilizing visible synchrotron radiation from a bending magnet has been designed and installed in CESR. The monitor employs a double-slit interferometer which has been successfully implemented to measure horizontal beam sizes over a wide range of beam currents. By varying the separation of the slits, beam sizes ranging from 50 to 500 microns can be measured with a resolution of approximately 5 microns. The method for extracting the horizontal beam size from the interference pattern is presented and its application to intrabeam scattering studies is described. A configuration for measuring the small vertical beam size is also discussed.

TUYB03

FFAG Experience and Future Prospects

acceleration, proton, focusing, betatron

1054

Y. Mori
Kyoto University, Research Reactor Institute, Osaka, Japan

This talk should outline the various FFAG accelerators that have been constructed, and discuss the operational experience with different machines. Common issues should be identified, and contrasting experiences highlighted. A frank assessment of the capability of FFAGs to meet the requirements for applications such as ion therapy, accelerator-driven subcritical reactors, and muon colliders should be followed by a description of the main objectives and challenges for future R&D.

Slides TUYB03 [14.162 MB]

TUOBB02

Commissioning of the PLS-II

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

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]

TUOAC03

Status of a Single-Aperture 11 T Nb3Sn Demonstrator Dipole for LHC Upgrades

dipole, collimation, status, magnet-design

1098

A.V. Zlobin, N. Andreev, G. Apollinari, E.Z. Barzi, R. Bossert, G. Chlachidze, V. Kashikhin, A. Nobrega, I. Novitski, D. Turrioni, R. Yamada
Fermilab, Batavia, USA
B. Auchmann, M. Karppinen, L. Oberli, L. Rossi, D. Smekens
CERN, Geneva, Switzerland

Funding: Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
The planned upgrade of the LHC collimation system includes two additional collimators to be installed in the dispersion suppressor areas of points 2, 3 and 7. The necessary longitudinal space for the collimators could be provided by replacing some 8.33 T NbTi LHC main dipoles with 11 T dipoles based on Nb3Sn superconductor and compatible with the LHC lattice and main systems. To demonstrate t his possibility Fermilab and CERN have started in 2011 a joint R&D program with the goal of building by 2014 a 5.5-m long twin-aperture dipole prototype suitable for installation in the LHC. The first step of this program is the development of a 2-m long single-aperture demonstration dipole with the nominal field of 11 T at the LHC nominal current of ~11.85 kA and 60 mm bore with ~20% margin. This paper describes the design, construction and test results of the single-aperture Nb3Sn demonstrator model for the LHC collimation system upgrade.

Slides TUOAC03 [5.812 MB]

TUEPPB003

Nonlinear Accelerator with Transverse Motion Integrable in Normalized Polar Coordinates

simulation, focusing, insertion, 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).

TUEPPB005

Novel Technique of Suppressing TBBU in High-energy ERLs

linac, HOM, SRF, electron

1122

V. Litvinenko
BNL, Upton, Long Island, New York, USA

Energy recovery linacs (ERLs) is emerging generation of accelerators promising revolutionize the fields of high-energy physics and photon sciences. One potential weakness of these devices is transverse beam-breakup instability, which may severely limit available beam current. In this paper I am presenting novel idea of using natural chromaticity in ERL arcs to suppressing TBBU instabilities. I present the theory of the process and two exact cases demonstrating that the threshold of TBBU instability could be raised by my orders of magnitude using this method.
* V.N. Litvinenko, Chromaticity of the lattice and beam stability in energy recovery linacs, submitted to PR ST-AB

TUPPC004

Study of a Lattice with a Lower Emittance at SOLEIL

emittance, dipole, optics, betatron

1155

R. Nagaoka, P. Brunelle, A. Nadji, L.S. Nadolski
SOLEIL, Gif-sur-Yvette, France

The paper introduces the first preliminary feasibility study made at SOLEIL towards a possible future upgrade of the lattice in furthermore reducing the horizontal emittance, so to raise the storage ring performance. The approach taken is to employ whatever emittance reduction methods available, by respecting the given constraints on the lattice structure and the optics, particularly the circumference, insertion device straights, the required optics behavior as well as its tunability. Specifically, the possibility of introducing superbends into the double bend lattice is pursued, which are beneficial to hard X-ray users and could simultaneously help reducing the emittance thanks to its longitudinally varying field profile. Although the present study shall mainly focus on the linear properties of the optical solutions found, optimization of nonlinear optics is also discussed in view of the large dependence of the latter on the former.

TUPPC005

Optimization of the SIS100 Nonlinear Magnet Scheme for Slow Extraction

extraction, sextupole, octupole, dynamic-aperture

1158

A. Saa Hernandez, M.M. Kirk, D. Ondreka, N. Pyka, S. Sorge, P.J. Spiller
GSI, Darmstadt, Germany

The SIS100 superconducting synchrotron was initially planned mainly for fast extraction of protons and heavy ions. Due to the delay of the construction of the SIS300 synchrotron, SIS100 has to be able to provide slowly extracted heavy ion beams to the experiments. To improve the robustness of the slow extraction from SIS100, a lattice review was performed, resulting in an optimization of the nonlinear magnet scheme. In the original scheme the Hardt condition cannot be established due to a collapse of the dynamic aperture caused by the chromatic sextupoles. In the optimized scheme the positions of the chromatic sextupoles are modified and octupoles are employed to compensate the second order effects of these sextupoles. In addition, the number of resonance sextupole magnets is reduced. With the new scheme, the Hardt condition can be established, leading to higher extraction efficiency. The separatrix can be freely adjusted, and closed orbit control is improved.

TUPPC013

Optimization of Lower Emittance Optics for the SPring-8 Storage Ring

optics, emittance, photon, brilliance

1182

Y. Shimosaki, K.K. Kaneki, M. Masaki, T. Nakamura, H. Ohkuma, J. Schimizu, K. Soutome, S. Takano, M. Takao
JASRI/SPring-8, Hyogo-ken, Japan

A design work of the present SPring-8 storage ring is in progress to improve its performance. The linear optics has been changed to reduce the natural emittance below the nominal of 3.4 nmrad at 8 GeV, and the nonlinear optics has been optimized with a genetic algorithm to suppress the amplitude-dependent tune shifts and to enlarge the dynamic aperture. As a preliminary study, the optics with the natural emittance of 2.4 nmrad at 8 GeV has been examined, theoretically and experimentally. In this optics, 1.5 times higher brilliance for 10 keV photons than the present can theoretically be expected for the standard undulator beamline. The improved optics design and its beam performance will be presented in detail. In this presentation, a optics for a future upgrade of the SPring-8 (SPring-8 II) will not be discussed, which is a full-scale major lattice modification, while the method we used in optimizing the nonlinear optics can also be adopted to the SPring-8 II*.
* Y. Shimosaki et al., "Design Study of Nonlinear Optics for a Very Low-emittance Lattice of the SPring-8 II," these proceedings.

TUPPC014

Design Study of Nonlinear Optics for a Very Low-emittance Lattice of the SPring-8 II

sextupole, emittance, resonance, optics

1185

Y. Shimosaki, K.K. Kaneki, T. Nakamura, H. Ohkuma, J. Schimizu, K. Soutome, M. Takao
JASRI/SPring-8, Hyogo-ken, Japan

A feasibility of a very low-emittance storage ring has been studied for an upgrade project, SPring-8 II. Its ultimate goal is to provide a superior brilliance for 0.5 ~ 100 keV photons. A sextupole bend lattice with the natural emittance of 70 pmrad at 6 GeV has been examined as the first candidate*. The nonlinear optics has been optimized to enlarge the dynamic aperture by correcting nonlinear resonances based on an isolated resonance Hamiltonian with thick lens approximation, and by non-interleaved sextupole method. A genetic algorithm, which has been examined to improve the performance of the present SPring-8**, will be adopted for detailed optimization of the tunes and sextupole strength to adjust the non-interleaved scheme and to correct higher order resonances. The correction scheme of nonlinear optics and its results will be presented in detail.
*Y. Shimosaki et al., IPAC’11, TUOAB01, p. 942 (2011).
**Y. Shimosaki et al., "Optimization of Lower Emittance Optics for the SPring-8 Storage Ring", these proceedings.

TUPPC015

Local Modification of Lattice of a Long Straight Section for Installing Small Gap In-vacuum Undulators at SPring-8

betatron, dynamic-aperture, sextupole, electron

1188

K. Soutome, T. Fujita, K. Fukami, K.K. Kaneki, C. Mitsuda, H. Ohkuma, M. Oishi, Y. Okayasu, S. Sasaki, J. Schimizu, Y. Shimosaki, M. Shoji, M. Takao, Y. Taniuchi, C. Zhang
JASRI/SPring-8, Hyogo-ken, Japan
M. Hasegawa, K. Kajimoto, T. Nakanishi
SES, Hyogo-pref., Japan

In the SPring-8 storage ring there are four magnet-free long straight sections (LSS) of about 30m. Recently we locally modified one of these sections by installing two quadrupole-triplets and divided it into three sub-sections. The vertical beta at the middle of each sub-section was lowered to 2.5m so that small gap in-vacuum undulators with a short period (min. gap: 5.2mm, period: 19mm) can be installed to build a high performance beamline for inelastic X-ray scattering. After modifying the lattice, however, the symmetry of the ring is lowered and, in general, it becomes difficult to keep sufficient dynamic aperture (DA) and momentum acceptance (MA). We solved this problem by combining the betatron phase matching, local chromaticity correction in LSS and cancellation of non-linear kicks due to sextupoles used for this correction. We could then recover DA and MA to almost the same level for the original one. The beam commissioning of the new lattice has successfully been finished, and from September 2011 it is used in user-operation. We will report our method of realizing a storage ring lattice having a very low symmetry and review the operation performance of the modified lattice.

TUPPC017

Orbit and Optics Correction to Realize Designed Machine Performance

optics, emittance, target, closed-orbit

1194

Y. Seimiya, S. Kamada, A. Morita, K. Ohmi, K. Oide
KEK, Ibaraki, Japan

It is difficult for actual accelerators to achieve the designed machine performance without appropriate correction or adjustment of magnet errors. By correction as magnets are aligned to design orbit, we aim to be realized the designed machine performance. However, it is not easy to estimate the design orbit in real accelerators. In KEKB and PF, beam position monitor(BPM) can be calibrated to the center of quadrupole magnet(QM). BPM and QM misalignments (except rotation misalignment) referring to design orbit can be estimated using assumption that these misalignments are coincident. This is, design orbit at BPM and QM can be derived.

TUPPC020

A Scheme for Horizontal-vertical Coupling Correction at SuperKEKB

coupling, simulation, optics, target

1203

H. Sugimoto, H. Koiso, A. Morita, Y. Ohnishi, K. Oide
KEK, Ibaraki, Japan

SuperKEKB is an 7 GeV electron and 4 GeV positron double ring collider project based on the nano beam scheme and is aimed to break the world's luminosity record. A horizontal flat beam is essential to realize the nano beam collisions. One of critical effect that induces unexpected coupling is machine error, such as magnet misalignment and field imperfection. Coupling correction, therefore, plays key role in the actual beam operation. In this study, we numerically explore a possible scheme for coupling correction in the SuperKEKB lattice. Some coupling measurement and correction methods are applied to the model lattice considering magnet misalignments and finite BPM resolution. Based on the results, the attainable smallest coupling in the actual SuperKEKB is discussed.

TUPPC025

Solaris Storage Ring Lattice Optimization with Strong Insertion Devices

optics, undulator, insertion, 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.

TUPPC027

Multi Objective Genetic Optimization for Linac Lattice of PAL XFEL

linac, electron, emittance, quadrupole

1224

C.H. Yi, M.-H. Cho, S.H. Kim, W. Namkung
POSTECH, Pohang, Kyungbuk, Republic of Korea
H.-S. Kang
PAL, Pohang, Kyungbuk, Republic of Korea
K.-J. Kim
ANL, Argonne, USA

Funding: Work supported by MEST and POSTECH Physics BK21 Program.
There are a large number of variables and objectives in design of XFEL linac lattices. Recently, most of accelerator physics field, are applying the multi-objective genetic algorithm (MOGA) for these kinds of problems. MOGA was applied to the PAL XFEL linac lattice design. Longitudinal position of all components was fixed before applying MOGA. RF parameters of RF cavities and bending angles of bunch compressors are selected as variables. Various beam parameters computed by ELEGANT were used as objectives. By using MOGA, new linac lattice designs with 2 and 3 bunch compressors was generated and their beam properties are presented in this paper.

TUPPC037

Update on LHeC Ring-Ring Optics

sextupole, insertion, optics, 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.

TUPPC041

A 3 TeV Muon Collider Lattice Design

quadrupole, emittance, dipole, collider

1254

Y. Alexahin, E. Gianfelice-Wendt
Fermilab, Batavia, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
A new lattice for 3 TeV c.o.m. energy with β^*=5mm was developed which follows the basic concept of the earlier 1.5 TeV design* but uses quad triplets for the final focus in order to keep the maximum magnet strength and aperture about the same as in 1.5 TeV case. Another difference is employment of combined-function magnets with the goal to lower heat deposition in magnet cold mass and to eliminate regions without bending field which produce “hot spots” of neutrino radiation that can be an issue at higher energy. The proposed lattice is shown to satisfy the requirements on luminosity, dynamic aperture and momentum acceptance.
* Y.Alexahin, E.Gianfelice-Wendt, A.Netepenko, Proc. IPAC10, Kyoto, May 2010, p. 1563

TUPPC043

Design of Accumulator and Compressor Rings for the Project-X Based Proton Driver

proton, linac, optics, synchrotron

1260

Y. Alexahin, D.V. Neuffer
Fermilab, Batavia, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
A Muon Collider (MC) and Neutrino Factory (NF), which may be considered as a step towards MC, both require high-power (~4 MW) proton driver providing short (<1m) bunches for muon production. However, the driver repetition rate required for these two machines is different: ~15 Hz for MC and ~60 Hz for NF. This difference necessitates employing two separate rings: one for accumulation of the proton beam from the Project-X linac in a few (e.g., 4) long bunches, the other for bunch compression - one by one for NF or all at a time for MC with simultaneous delivery to the target. The lattice requirements for these two rings are different: the momentum compaction factor in the accumulator ring should be large (and possibly negative) to avoid the microwave instability, while the compressor ring can be nearly isochronous in order to limit the required RF voltage and reduce the dispersion contribution to the beam size. In the present report we consider ring lattice designs which achieve these goals.

TUPPC047

New Storage Ring Lattice for the Duke FEL Wiggler Switchyard System

wiggler, FEL, storage-ring, quadrupole

1272

H. Hao, J.Y. Li, Y.K. Wu
FEL/Duke University, Durham, North Carolina, USA

Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
The Duke storage ring is a dedicated drive for the OK-4 FEL and OK-5 FEL, and for the state-of-the-art Compton gamma-ray source, High Intensity Gamma-Ray Source (HIGS). To produce FEL lasing below 190 nm and gamma-ray beams above 100 MeV, the FEL system needs to be upgraded by adding two helical OK-5 wigglers to increase the FEL gain with four OK5 wigglers for the VUV operation. To simultaneously preserve the linear polarization capability of the gamma-ray beam produced by the planar OK-4 FEL, a wiggler switchyard system is under development which will enable the switch between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight. In this work, we present the new magnetic lattice designed for the operation of the wiggler switchyard system. This new lattice is developed with great flexibility for the operation with different numbers of FEL wigglers, variable betatron tunes, and adjustable electron beam sizes at the collision point for the HIGS. In addition, the new lattice is developed for the operation in a wide range of energies, from 280 MeV to 1.2 GeV, with proper nonlinear dynamics compensations in order to realize a large dynamic aperture.

TUPPC048

Online Physics Model Platform

controls, EPICS, simulation, monitoring

1275

P. Chu, Y. Zhang
FRIB, East Lansing, Michigan, USA
C. Benatti, V. Vuppala
NSCL, East Lansing, Michigan, USA
D. Dohan, G. Shen
BNL, Upton, Long Island, New York, USA
J. Wu
SLAC, Menlo Park, California, USA

Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
For a complex accelerator such as the Facility for Rare Isotope Beams (FRIB), a transfer matrix based online model might not be sufficient for the entire machine. On the other hand, if introducing another modelling tools, physics applications have to be rewritten for all modelling tools. A platform which can host multiple modelling tools would be ideal for such scenario. Furthermore, the model platform along with infrastructure support can be used not only for online applications but also for offline purposes with multi-particle tracking simulation. In order to achieve such a platform, a set of common physics data structures has to be set. XAL's accelerator hierarchy based data structure is a good choice as the common structure for various models. Application Programming Interface (API) for physics applications should also be defined within a model data provider. A preliminary platform design and prototype is discussed.

TUPPC056

Optics Measurements and Corrections at RHIC

optics, quadrupole, proton, luminosity

1299

M. Bai, J.N. Aronson, M. Blaskiewicz, Y. Luo, V.H. Ranjbar, G. Robert-Demolaize, S.M. White
BNL, Upton, Long Island, New York, USA
G. Vanbavinckhove
CERN, Geneva, Switzerland

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The further improvement of RHIC luminosity performance requires more precise understanding of the RHIC modeling. Hence, it is necessary to minimize the beta-beat, deviation of measured beta function from the calculated beta functions based on an model. The correction of beta-beat also opens up the possibility of exploring operating RHIC polarized protons at a working point near integer, a preferred choice for both luminosity as well as beam polarization. The segment-by-segment technique for reducing beta-beat demonstrated in the LHC operation for reducing the beta-beat was first tested in RHIC during its polarized proton operation in 2011. It was then fully implemented during the RHIC polarized proton operation in 2012. This paper reports the commissioning results. Future plan is also presented.

TUPPC058

Beam Energy Variation with Dipole Fault

dipole, sextupole, closed-orbit, simulation

1305

Y. Li, S. Krinsky
BNL, Upton, Long Island, New York, USA

Funding: Supported by Department of Energy Contract No. DE-AC02-98CH10886.
The effect of dipole faults and closed orbit correction on the beam energy is studied both analytically and numerically using the ELEGANT code. Motivated by top-off safety analysis, we consider the case of single dipole faults and study how large an error can be compensated by the closed orbit correction system before the beam is lost.

TUPPC059

Extraction of the Lie Map from Realistic 3D Magnetic Field Map

dipole, quadrupole, extraction, dynamic-aperture

1308

Y. Li
BNL, Upton, Long Island, New York, USA
X. Huang
SLAC, Menlo Park, California, USA

Funding: Supported by Department of Energy Contract No. DE-AC02-98CH10886.
We present a method to extract the Lie map of any arbitrary accelerator magnet from its actual 3D field map. After fitting a Taylor map from multi-particle tracking trajectories through the actual field, we factorize the map into a Lie map using Dragt-Finn's method. This method is validated by comparing with COSY-infinity for a soft-edge quadrupole model. Applications of extracting symplectic maps for the SPEAR and NSLS-II dipoles are shown as examples. A comparison of the map-tracking results against the direct field-integration-based method also is given.

TUPPC070

Alternating Spin Aberration Electrostatic Lattice for EDM Ring

simulation, quadrupole, proton, storage-ring

1332

Y. Senichev, R. Maier, D. Zyuzin
FZJ, Jülich, Germany
M. Berz
MSU, East Lansing, Michigan, USA

The idea of the electric dipole moment search using the storage ring (SrEDM) with polarized beam is realized under condition of the long-time spin coherency of all particles, the time during which the RMS spread of the spin orientation of all particles in the bunch reaches one radian. Following the requirements of the planned EDM experiment, the SCT should be more than 1000 seconds. During this time each particle performs about 10⁹ turns in the storage ring moving on different trajectories through the optics elements. At such conditions the spin-rotation aberrations associated with various types of space and time dependent nonlinearities start to play a crucial role. In this paper we consider a new method based on the alternating spin drift, causing it to rotate alternately, thereby limiting the growth of aberrations at one order of magnitude lower. As a result, using this method we can achieve the SCT of the order of 5000-6000 seconds. The difficulties of these studies are still in the fact that the aberrations growth observed in the scale of a 10⁹ turns. For the study we use an analytical method in composition with a numerical simulation by COSY Infinity.

TUPPC071

Comparison of Different Numerical Modelling Methods for Beam Dynamics in Electrostatic Rings

simulation, quadrupole, optics, proton

1335

D. Zyuzin, R. Maier, Y. Senichev
FZJ, Jülich, Germany
S.N. Andrianov, A.N. Ivanov
St. Petersburg State University, St. Petersburg, Russia
M. Berz
MSU, East Lansing, Michigan, USA

To search the electric dipole moment was proposed to use polarized protons at the so-called "magic" momentum of 0.7 GeV/c in an electric storage ring. For studying beam dynamics in electrostatic rings different computational methods can be used. We used differential algebra methods realized in COSY Infinity and integrating program with symplectic Runge-Kutta methods. These methods were observed and compared for orbital and spin motion.

TUPPC072

Modeling of Matching Channel for Accelerator Complexes

controls, booster, quadrupole, dipole

1338

E.A. Podzyvalov, S.N. Andrianov
St. Petersburg State University, St. Petersburg, Russia
D. Zyuzin
FZJ, Jülich, Germany

Practically modern accelerator facility can be considered as a composite machines. Therefore it is necessary to consider special matching channels to joint all accelerator components together. For such channels advance various requirements, which can be formulated in the form of criteria sets. In this paper considered a global optimization concept allows to find appropriate solutions sets. This approach is demonstrated on the problem of modeling the matching channels for NICA accelerator complex.

TUPPC073

Frequency Map Analysis for SuperB

resonance, dynamic-aperture, emittance, sextupole

1341

S.M. Liuzzo, M.E. Biagini, P. Raimondi
INFN/LNF, Frascati (Roma), Italy
T. Demma
LAL, Orsay, France
Y. Papaphilippou
CERN, Geneva, Switzerland

The frequency map analysis is applied to the SuperB HER and LER lattices including the Final Focus, in order to understand the dynamic aperture limitation and provide insight for a working point optimization. In this respect, frequency and diffusion maps are evaluated applying random magnet misalignments and tilts, before and after correction of orbit, dispersion and coupling using Low Emittance Tuning techniques. The same analysis is performed for on and off momentum particles. The lattice properties are further investigated using working point scans and the correction of non linear resonance driving terms and amplitude detuning.

TUPPC079

Tracking LHC Models with Thick Lens Quadrupoles: Results and Comparisons with the Standard Thin Lens Tracking

quadrupole, simulation, optics, dipole

1356

M. Giovannozzi, H. Burkhardt, T. Risselada
CERN, Geneva, Switzerland

So far, the massive numerical simulation studies of the LHC dynamic aperture were performed using thin lens models of the machine. This approach has the clear advantage of speed, but it has also the disadvantage of requiring re-matching of the optics from the real thick configuration to the thin one. Furthermore, as the figure-of-merit for the re-matching is the agreement between the beta-functions for the two model, while the quadrupole gradients are left free parameters, the effect of the magnetic multipoles might be affected by this approach and in turn the dynamic aperture computation. In this paper the new approach is described and the results for the dynamic aperture are compared with the old approach, including detailed considerations on the CPU-time requirements.

TUPPC080

Investigations of Scaling Laws of Dynamic Aperture with Time for Numerical Simulations including Weak-Strong Beam-Beam Effects

simulation, injection, dynamic-aperture, beam-beam-effects

1359

M. Giovannozzi
CERN, Geneva, Switzerland
E. Laface
ESS, Lund, Sweden

A scaling law describing the time-dependence of the dynamic aperture, i.e., the region of phase space where stable motion occurs, was proposed in previous papers about ten years ago. It was shown that dynamic aperture has a logarithmic dependence on time, which would be suggested by some fundamental theorems of the theory of dynamical systems. So far, such a law was applied to single-particle effects only, i.e., the only source of non-linear effects was the magnetic imperfections. In this paper an attempt is made to extend the scaling law to the case of weak-strong beam-beam effects. The results of numerical simulations performed, including both non-linear magnetic imperfections and weak-strong beam-beam effects, are presented and discussed in detail.

TUPPC090

Beam Physics of Integrable Optics Test Accelerator at Fermilab

simulation, betatron, resonance, optics

1371

A. Valishev, S. Nagaitsev
Fermilab, Batavia, USA
V.V. Danilov
ORNL, Oak Ridge, Tennessee, USA
D.N. Shatilov
BINP SB RAS, Novosibirsk, Russia

Funding: Fermi Research Alliance, LLC operates Fermilab under Contract DE-AC02-07CH11359 with the US Department of Energy.
Fermilab's Integrable Optics Test Accelerator is an electron storage ring designed for testing advanced accelerator physics concepts, including implementation of nonlinear integrable beam optics and experiments on optical stochastic cooling. The machine is currently under construction at the Advanced Superconducting Test Accelerator facility. In this report we present the goals and the current status of the project, and describe the details of machine design. In particular, we concentrate on numerical simulations setting the requirements on the design and supporting the choice of machine parameters.

TUPPC100

On Quantum Integrable Systems

plasma, synchrotron, focusing, betatron

1392

V.V. Danilov
ORNL, Oak Ridge, Tennessee, USA
S. Nagaitsev
Fermilab, Batavia, USA

Funding: This research is sponsored by Oak Ridge National Lab, under Contract No. DE-AC05-00OR22725, and Fermi National Lab, under Contract No. DE-AC02-07CH11359.
Many quantum integrable systems are obtained using an accelerator physics technique known as Ermakov (or normalized variables) transformation. This technique was used to create classical nonlinear integrable lattices for accelerators and nonlinear integrable plasma traps. Now, all classical results are carried over to a nonrelativistic quantum case.

TUPPC102

Simulation Study of Beam-beam Effects in Ion Beams with Large Space Charge Tuneshift

space-charge, simulation, synchrotron, collider

1398

C. Montag
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.
During low-energy operations with gold-gold collisions at 3.85 GeV beam energy, significant beam lifetime reductions have been observed due to the beam-beam interaction in the presence of large space charge tuneshifts. These beam-beam tuneshift parameters were about an order of magnitude smaller than during regular high energy operations. To get a better understanding of this effect, simulations have been performed. Recent results are presented.

TUPPD003

Optimisation of Cooling Lattice Based on Bucked Coils for the Neutrino Factory

factory, emittance, simulation, cavity

1407

A. Alekou, J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

The ionisation cooling technique will be used at the Neutrino Factory to reduce the transverse phase space of the muon beam. For efficient cooling, high average RF gradient and strong focusing are required to be applied in the cooling channel. However, high magnetic field at the position of the RF cavities induces electric field breakdown and therefore, a novel configuration, the Bucked Coils lattice, has been proposed to mitigate this problem. The Bucked Coils lattice has significantly lower magnetic field in the RF cavities by using coils of different radius and opposite polarity. This paper presents the optimisation of this lattice, its cooling performance, together with the preliminary conceptual engineering design.

TUPPP002

GLASS Study of the Canadian Light Source Storage Ring Lattice

dynamic-aperture, emittance, quadrupole, sextupole

1602

W.A. Wurtz, L.O. Dallin
CLS, Saskatoon, Saskatchewan, Canada

GLASS is a technique for finding all potential operating points of a storage ring lattice by examining all possible configurations of the linear lattice. The Canadian Light Source (CLS) storage ring uses three quadrupole families, making it computationally efficient to use GLASS to study the lattice with unbroken symmetry. CLS does not employ harmonic sextupoles and has only two families of chromatic sextupoles. We can exhaust the sextupole degrees of freedom by requiring the horizontal and vertical chromaticities to be both zero. With no remaining free parameters in our lattice, it is possible to calculate dynamic aperture and momentum acceptance for select regions of interest uncovered by the GLASS scan. We find two regions with reasonable dynamic aperture and momentum acceptance: the region where we presently operate and a region that can be accessed by reversing the polarity of one quadrupole family.

TUPPP013

Effects of Multipoles in Dynamic Aperture of the ILSF Storage Ring

multipole, dynamic-aperture, sextupole, quadrupole

1632

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

Dynamic aperture of a synchrotron light source shrinks to small value due to the multipole errors caused by magnet design. In the ILSF storage ring, the tolerance of magnets has been taken into account in the simulation and sextupole magnets reoptimized to improve the dynamic aperture. This paper yields the evaluated dynamic aperture include of multipole errors.

TUPPP014

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

emittance, quadrupole, insertion, 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.

TUPPP015

Status and Recent Progress of SPring-8

coupling, emittance, storage-ring, optics

1638

H. Ohkuma
JASRI/SPring-8, Hyogo-ken, Japan

The SPring-8 is an 8 GeV synchrotron radiation facility that has been in operation since 1997. The SPring-8 has been operated well and total user time has reached more than 53,700 hours, 75% of the total operation time. The average user time per year is about 4,000 hours. The average availability is about 98% in the past 15 years. The operational status and recent progress overview of SPring-8 is presented: the local lattice modification of 30-m long straight section for installing small gap (min. gap is 5.2 mm) in-vacuum undulators, the emittance coupling correction for the vertical beam size reduction, the test operation of low energy operation for the energy saving, and the study of lower emittance optics for the present SPring-8 storage ring. An outline of a future upgrade with a full-scale major lattice modification is also presented. We also present a little about recent progress of SPring-8 injecting accelerators.

TUPPP017

Lattice Design of the SSRF Storage Ring with Superbend

emittance, photon, dipole, optics

1644

S.Q. Tian, B.C. Jiang, H.H. Li, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

The SSRF storage ring is being investigated by upgrading with normal conducting superbend of 3 T. The bending magnets are shortened, and thus some additional straight sections with the length of about 2 m are created in the center of the arc cell. They can be used to install more insertion devices. The lattice adjustment and the optics design are presented in this paper, where much efforts are made to maintain the effective emittance along the ring with respect to the nominal optics.

TUPPP018

Design and Commissioning of the Very Low Emittance Optics in the SSRF Storage Ring

emittance, optics, injection, storage-ring

1647

S.Q. Tian, J. Chen, B.C. Jiang, Y.B. Leng, H.H. Li, L.Y. Yu, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

In synchrotron radiation light sources, there are continuous efforts to lower the storage ring emittance and thus increase its photon beam brightness. The lowest effective emittance of SSRF is found by a systematic method. Results of design and commissioning of this kind of optics are presented, of which the beam emittance is smaller than the nominal one by 1 nm.rad. The measured beam parameters agree well with the design ones.

TUPPP022

Beam Optics Measurements during ALBA Commissioning

quadrupole, optics, emittance, storage-ring

1656

M. Muñoz, G. Benedetti, J. Campmany, D. Einfeld, 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. This paper reviews the results of the modeling of the lattice and the agreement with the LOCO measurement of the machine; the performance of the beta beating correction (critical in the ALBA case due to the large gradient in the bending magnet and the low number of quadrupole families), including effect of insertion devices; the lifetime measurement; tune scans; tune shift with horizontal amplitude; and the general agreement of the machine to the model using during the design. A brief summary of the modeling of the injector chain is included.

TUPPP024

Recent Progress on the MAX IV 1.5 GeV Storage Ring Lattice and Optics

storage-ring, dipole, vacuum, sextupole

1662

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

Construction of the MAX IV facility started in 2010 and commissioning is expected to begin in 2014. Once completed, 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 lattice and optics of the 1.5 GeV storage ring have been modified as a result of detailed magnet and vacuum system design. This paper discusses the lattice and optics changes as well as their effects.

TUPPP027

Subpicosecond Laser Slicing X-Ray Source for Time-resolved Research at TPS

wiggler, laser, emittance, photon

1671

W.K. Lau, M.C. Chou, C.-S. Hwang, A.P. Lee, Y.-C. Liu, G.-H. Luo
NSRRC, Hsinchu, Taiwan
N.Y. Huang
NTHU, Hsinchu, Taiwan

The 3 GeV Taiwan Photon Source (TPS) under construction at NSRRC should be ready for user run in 2014. X-ray users in many research areas will then be benefited. However, there has been a growing interest in ultrafast time-resolved research in the island. The feasibility of using ultrafast laser for electron-beam slicing at TPS to produce sub-picosecond x-ray pulses is being investigated recently. The design and layout of a laser slicing scheme with W250 wiggler as the energy modulator in a 7 m medium straight section and EPU48 and IU22 radiators in other straight sections will be presented. It will offer the unique opportunity to gain experience in experimental techniques needed for FEL science.

TUPPP034

BPM Gains and Beta Function Measurement Using MIA and FPGA BPMs at the APS

betatron, optics, quadrupole, feedback

1686

C.-X. Wang, G. Decker, H. Shang, C. Yao
ANL, Argonne, USA
D. Ji
IHEP, Beijing, People's Republic of China

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The broadband BPM system at the Advanced Photon Source (APS) is being upgraded with FPGA-based beam history modules, which fix problems in the old history modules and increase functionality. Using these new turn-by-turn BPMs and the newly developed real-time feedback system, measurement of BPM gains, beta function and other optics functions are being developed based on model-independent analysis of turn-by-turn data and model fitting, aiming at quasi-real-time and high-accuracy optics measurement. We will discuss our effort, especially experience with strong nonlinearity and wakefields typical of 3rd-generation light sources.

TUPPP037

Status of the ALS Brightness Upgrade

brightness, insertion, 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.

TUPPP039

Vertical Dispersion Bump Design for Femto-second Slicing Beamline at the ALS

coupling, quadrupole, emittance, radiation

1698

C. Sun, C. Steier, W. Wan
LBNL, Berkeley, California, USA

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Femto-second (fs) slicing beamline has been brought to the operation at the Advanced Light Source (ALS) since 2002. It employs the resonant interaction of an electron bunch with a fs laser beam in a wiggler to energy-modulate a short section of the bunch. The induced energy modulation is then converted to a transverse displacement using a vertical dispersion bump downstream of the wiggler. Thus, the radiation from the fs pulse can be separated from the main bunch radiation. The current dispersion bump design has proved to be an effective and reliable one. However, the ALS storage ring lattice is under an upgrade to improve its brightness. After the completion of the upgrade, a new low emittance will be implemented, and the current dispersion bump design needs to be modified to provide the adequate vertical displacement, while minimizing the vertical emittance and spurious dispersion. In this paper, we present the new design of a vertical dispersion bump using Multi-Objective Genetic Algorithm (MOGA) for the ALS upgrade lattice.

TUPPP062

Start to End Simulation of Three Bunch Compressor Lattice for PAL XFEL

FEL, emittance, linac, simulation

1738

H.-S. Kang, M.-H. Cho, J.H. Han, T.-H. Kang, I.S. Ko
PAL, Pohang, Kyungbuk, Republic of Korea
C.H. Yi
POSTECH, Pohang, Kyungbuk, Republic of Korea

The PAL XFEL is a 0.1-nm hard X-ray FEL project starting from 2011 to finish in 2014, which aims at achieving higher photon flux than 10¹² photons/pulse at 0.1 nm using a 10 GeV electron linac. The PAL XFEL is designed to have a hard x-ray undulator line at the end of linac and a branch line at 2.65 GeV point for soft X-ray undulator line. The three bunch compressor lattice (3-BC) is chosen to minimize emitance growth due to CSR and minimize correlated energy spread. The 3-BC lattice makes it possible to operate soft X-ray FEL undulator line simultaneously and independently from hard X-ray FEL undulator line.

TUPPP069

A Compact, Modular Electron Beam Delay Line for Use in Novel Free-Electron Laser Schemes

undulator, quadrupole, FEL, electron

1759

J.K. Jones, J.A. Clarke, N. Thompson
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Two Free-Electron Laser (FEL) schemes have been proposed, for the generation of attosecond pulse trains* and for the improvement of the longitudinal coherence of SASE FELs**, in which repeated electron delays are implemented within the undulator lattice. To obtain the maximum performance and flexibility from these schemes it is advantageous to use an electron delay line that satisfies the isochronicity conditions, as well as being compact, modular and, ideally, variable. In this paper we present initial designs for such a system, along with simulations of its performance. We investigate both in-undulator and out-of-undulator designs, and compare the applicability of each for various aspects of the FEL design, as well as commenting on the mechanical and magnetic implications of the schemes.
* N.R. Thompson and B.W.J. McNeil. Phys. Rev. Lett. 100, 203901 (2008).
** N.R. Thompson, D.J. Dunning and B.W.J. McNeil, IPAC2010, TUPE050, p. 2257 (2010).

TUPPR003

The Design of Spin-Rotator with a Possibility of Helicity Switching for Polarized Positron at the ILC

positron, solenoid, damping, polarization

1813

L.I. Malysheva, O.S. Adeyemi, V.S. Kovalenko, G.A. Moortgat-Pick, A. Ushakov
University of Hamburg, Hamburg, Germany
A.F. Hartin, B. List, N.J. Walker
DESY, Hamburg, Germany
S. Riemann, F. Staufenbiel
DESY Zeuthen, Zeuthen, Germany

Funding: Work supported by German Federal Ministry of education and research. Joint Research project R&D Accelerator Spin Management, contract N 05H10CUE
At the ILC, positrons are produced with longitudinal polarization at the source. In order to preserve the polarization, the spin must be rotated into the vertical direction prior to injection into the damping rings. A new design of the spin rotator is presented that allows to randomly switch between the two vertical orientations between successive bunch trains. After rotating the spin back to longitudinal polarization, this corresponds to a choice between the two possible helicity states at the interaction point. The fast flipping is achieved by inserting two parallel spin rotation sections with opposite polarities, with a fast magnet that allows to choose between the sections.

TUPPR008

One 233 km Tunnel for Three Rings: e⁺e^-, p-pbar, and μ⁺+μ⁻

collider, dipole, emittance, luminosity

1828

G.T. Lyons, L.M. Cremaldi, A. Datta, M. Duraisamy, T.H. Luo, D.J. Summers
UMiss, University, Mississippi, USA

Funding: Supported by DE-FG05-91ER40622
In 2001, a cost analysis was conducted to build a 233 km circumference tunnel in northern Illinois for a Very Large Hadron Collider (VLHC). Here we outline the implementations of e⁺e⁻, proton anti-proton, and μ⁺+ μ⁻ collider rings in such a tunnel using recent technological innovations. The 500 GeV e⁺e⁻ collider employs a Crab Waist Crossing, ultra low emittance damped bunches, a vertical IP focal length of 0.06 cm, 12 GV of superconducting RF, and 0.026 Tesla low coercivity, grain oriented silicon steel/concrete dipoles. The 40 TeV proton anti-proton collider uses the high intensity Fermilab anti-proton source, exploits high cross sections for proton anti-proton production of high mass states, and uses 2 Tesla 0.005% ultra low carbon steel/YBCO superconductor magnets run with liquid neon. The 40 TeV muon ring ramps the 2 Tesla superconducting magnets at 8 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 2 to 20 TeV in 72 orbits with 72% survival, and mitigates neutrino radiation with a phase shifting, roller coaster FODO lattice.*
* G. T. Lyons, http://arxiv.org/pdf/1112.1105

TUPPR013

Design Integration and Vision Sharing for the ILC

linear-collider, linac, collider, damping

1837

B. List, L. Hagge, S. Sühl, N.J. Walker, N. Welle
DESY, Hamburg, Germany

The Global Design Effort for the International Linear Collider is currently preparing the Technical Design Report, which will be released in early 2013. The starting point of a consistent and correct design is the accelerator lattice, which defines the layout of the machine. Integrating the lattice geometrically and optically provides the basis for civil engineering and conventional facilities planning and finally the cost estimate. Tools that provide three-dimensional visualization of the lattice and tunnel help to perform the design integration and allow sharing a common vision of the final accelerator. We will present the process that was established to arrive at such an integrated design and the tools that were developed to support that process by analyzing and visualizing lattice files.

TUPPR022

Traditional Final Focus System for CLIC

luminosity, collider, linear-collider, quadrupole

1858

H. Garcia, A. Latina, R. Tomás
CERN, Geneva, Switzerland
H. Garcia
UPC, Barcelona, Spain

Next generation linear colliders needs a very strong focalisation to reach nanometer beam size at the Interaction Point. This task and the chromatic correction generated by the strong lenses is done by the Final Focus System. A traditional Final Focus System based on dedicated chromaticity correction sections is presented as an alternative for CLIC Final Focus. The scheme of the lattice is shown and some tolerances in the Final Doublet are calculated. A systematic tuning using Simplex algorithm and sextupole knobs is performed. The complete comparison to the Local Chromaticity correction scheme is presented.

TUPPR031

Experimental Verification of the CLIC Decelerator with theTest Beam Line in the CLIC Test Facility 3

extraction, quadrupole, alignment, linac

1885

R.L. Lillestøl, S. Döbert, M. Olvegård, A. Rabiller, G. Sterbini
CERN, Geneva, Switzerland
E. Adli
University of Oslo, Oslo, Norway

The Test Beam Line in the CLIC Test Facility 3 is the first prototype of the CLIC drive beam decelerator. The main purpose of the experiment is to demonstrate efficient 12 GHz rf power production and stable transport of an electron drive beam during deceleration. The Test Beam Line consists of a FODO structure with high precision BPMs and quadrupoles mounted on mechanical movers for precise beam alignment. Nine out of the planned 16 Power Extraction and Transfer Structures have currently been installed and commissioned. We correlate rf power production measurements with the drive beam deceleration measurements, and compare the two measurements to the theoretical predictions. We also discuss the impact of the drive beam bunch length and bunch combination on the measurements.

TUPPR035

A Comparative Study for the CLIC Drive Beam Decelerator Optics

optics, quadrupole, injection, alignment

1897

G. Sterbini, D. Schulte
CERN, Geneva, Switzerland
E. Adli
University of Oslo, Oslo, Norway

The baseline for the CLIC drive beam decelerators optics consists of a 2-m-long FODO cell. This solution was adopted to have strong focusing in order to mitigate the effect of the PETS wakefields and to minimize the drive beam envelope. Taking into account the most recent PETS design, we compare the performance of the baseline FODO cell with a proposal that consider twice longer FODO cell. Despite of the expected cost in term of performance, the reduction of the complexity of the system due to the halving of the number of quadrupoles can be beneficial for the overall optimization of the decelerator design.

TUPPR041

Update on ILC Positron Source Start-to-End Simulation

positron, electron, undulator, linac

1909

W. Liu, W. Gai
ANL, Argonne, USA

As a result of the changes in the new ILC base line, there are many changes in the positron source beamline layouts and thus a new lattice design is required. According to the changes in the ILC baseline, a new lattice design for the ILC positron source has been developed at ANL. In this paper, both the new ILC positron source beamline lattice and the corresponding start to end simulation results are presented.

TUPPR060

Detection of Ground Motion Effects on the Beam Trajectory at ATF2

ground-motion, quadrupole, extraction, linear-collider

1954

Y. Renier, J. Pfingstner, D. Schulte, R. Tomás
CERN, Geneva, Switzerland

The ATF2 experiment is currently demonstrating the feasibility of the beam delivery system for the future linear collider. The tunning is very critical to obtain the nanometer vertical beam size at the interaction point and in the case of CLIC, ground motion effects on the beam must be corrected. In this respect, as a proof of principle of a ground motion feed forward, the ground motion effects on the beam trajectory are extracted from the beam position monitor readings.

TUPPR063

Investigation into Electron Cloud Effects in the ILC Damping Ring Design

photon, vacuum, wiggler, electron

1963

J.A. Crittenden, J.V. Conway, G. Dugan, M.A. Palmer, D. L. Rubin
CLASSE, Ithaca, New York, USA
L.E. Boon, K.C. Harkay
ANL, Argonne, USA
M.A. Furman
LBNL, Berkeley, California, USA
S. Guiducci
INFN/LNF, Frascati (Roma), Italy
M.T.F. Pivi, L. Wang
SLAC, Menlo Park, California, USA

Funding: Work supported by the U.S. Department of Energy DE-SC0006506
We report modeling results for electron cloud buildup in the ILC damping ring lattice design. Updated optics, wiggler magnet, and vacuum chamber designs have recently been developed for the 5-GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effect of photon scattering on the interior of the vacuum chamber. Operational implications of the resulting electron cloud buildup will be discussed.

TUPPR065

Wiggler Magnet Design Development for the ILC Damping Rings

wiggler, damping, vacuum, linear-collider

1969

J.A. Crittenden, M.A. Palmer, D. L. Rubin
CLASSE, Ithaca, New York, USA

Funding: Work supported by the U.S. Department of Energy DE-SC0006506.
The baseline damping ring lattice design for the International Linear Collider employs nearly 60 2.2-m-long superconducting wiggler magnets to provide the damping necessary to achieve the specified horizontal emittance. We describe the OPERA-based finite-element model developed for the 14-pole, 30-cm period, 7.62-cm gap superferric design which meets the 2.1 T peak field requirement. Transfer functions and field uniformity results are discussed. We present results for the accuracy of the optimized analytic model needed for symplectic tracking algorithms, as well as implications for the updated engineering design.

TUPPR066

Characterization of Single Particle Dynamics for the International Linear Collider Damping Ring Lattice

damping, emittance, wiggler, multipole

1972

J.P. Shanks, J.A. Crittenden, M.A. Palmer
CLASSE, Ithaca, New York, USA
D.L. Rubin
Cornell University, Ithaca, New York, USA

Funding: DOE Award DE-SC0006506
The baseline design for the International Linear Collider damping rings is a 3.2 km circumference racetrack, with 5 GeV beam energy. The transverse damping time is 26 ms and the normalized horizontal emittance 5 mm-mrad. Nearly 60 2.2-m-long superconducting wigglers per ring increase the radiation damping rate by an order of magnitude and reduce horizontal emittance by a factor of 5. We characterize the sensitivity to magnet misalignments and field errors, and establish the minimum numbers of corrector magnets and beam position monitors required for tuning vertical emittance to less than 20 nm-rad. We validate the specified tolerable guide field multipole errors consistent with adequate dynamic aperture. Tune scans are used to identify stable working points. In tracking studies we use a wiggler model based on fits to 3-dimensional field maps.

TUPPR070

High-Gradient Photonic Band-gap (PBG) Structure Breakdown Testing at Ku-Band

diagnostics, HOM, damping, coupling

1984

B.J. Munroe, A.M. Cook, M.A. Shapiro, R.J. Temkin
MIT/PSFC, Cambridge, Massachusetts, USA

Photonic Band-gap (PBG) structures continue to be a promising area of research forfuture accelerator structures. Previous experiments at X-Band have demonstrated that PBG structures can operate at high gradient and low breakdown probability, provided that pulsed heating is controlled. Two single-cell standing-wave structures have been constructed at MIT to investigate breakdown performance of PBG structures. A metallic structure with small rods will be used to test performance with very high surface temperature rise, while an over-moded structure with dielectric rods will investigate alternative solutions to the issue of surface temperature rise. Both structures are expected to reach gradients of at least 100 MV/m and will utilize novel diagnostics, including fast camera imaging and optical spectroscopy of breakdowns.

TUPPR071

Experimental High-Gradient Testing of an Elliptical-Rod Photonic Band-Gap (PBG) Structure at X-Band

damping, wakefield, klystron, HOM

1987

B.J. Munroe, M.A. Shapiro, R.J. Temkin
MIT/PSFC, Cambridge, Massachusetts, USA
V.A. Dolgashev, S.G. Tantawi, A.D. Yeremian
SLAC, Menlo Park, California, USA
R.A. Marsh
LLNL, Livermore, California, USA

An 11.4 GHz Photonic Band-gap (PBG) structure where the rods in the inner row have an elliptical cross-section has been designed at MIT and tested at high power and high repetition rate at SLAC. This structure exhibits lower surface magnetic fields on the rods relative to previous round-rod PBG structures tested at SLAC, which reduces the ohmic heating of the rod surface in an effort to reduce pulsed heating damage. This improved PBG structure was tested experimentally such as to avoid excessively high breakdown rates and surface temperature rise. The structure demonstrated performance comparable to disc-loaded waveguide (DLWG) structures with the same iris geometry, achieving greater than 100 MV/m gradient at a breakdown probability of less than 10-3 per pulse per m for 150 ns pulses. This level of performance demonstrates that elliptical-rod PBG structures could be candidates for future accelerator applications.

TUPPR085

Recycler Chromaticities and End Shims for NOvA at Fermilab

sextupole, quadrupole, dynamic-aperture, dipole

2023

M. Xiao
Fermilab, Batavia, USA

In era of NOvA operation, it is planned to slip-stack six on six Booster proton batches in the Recycler ring for a total intensity of 5×10¹³ protons/cycle. During the slip-stacking, the chromaticities are required to be jumped from (-2,-2) to (-20,-20). However, they can only be adjusted to (-12,-12) from (-2,-2) using existing 2 families of powered sextupoles. On the other hand, the presently designed Recycler lattice for Nova replaces the 30 straight section with 8 “D-D half FODO cells”. We use 3 quads in a half-cell to obtain the working point under the limit of the feasible quad strength, and the maximum beta-function in this section cannot be less than 80 m. In this paper, we re-designed the end shims of the permanent magnets in the ring lattice with appropriate quadrupole and sextupole components to meet both chromaticity and tune requirements. We are able to use 2 quads in a half cell in RR30 straight section within feasible quad strength. The maximum beta-functions are also lowered to around 55 m. The dynamic aperture tracking has been done using MAD to simulate the scenario of beam injection into the Recycler ring for Nova.

WEPPD020

Vacuum System for TPS Booster

vacuum, booster, ion, electron

2540

C.M. Cheng, C.K. Chan, C.L. Chen, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh
NSRRC, Hsinchu, Taiwan

The TPS booster is designed for lower beam emittance and 3GeV full energy injection ramped up from 150MeV. It is a synchrotron accelerator of 496.8m in circumference and located concentric with the electron storage ring in the same tunnel. The vacuum system for the booster is divided into six super periods and each has nine bending magnet chambers. The beam duct is made of thin stainless steel tube extruded to the elliptical cross section with inner diameters of 35 mm×20 mm and thickness of 0.7 mm. All the chambers will be supported on the inner wall of the tunnel. The straightness of the extruded thin chambers is controlled within 2.5 mm in 4 m length. The bending chamber is made by mechanical bending from the straight tube. All the beam ducts will be chemical cleaned prior to welding, with flanges or BPM chambers, to form the long chambers in the clean room before installation. The arrangement of vacuum pumps are distributed to fulfill an average pressure of ＜1×10^-6 Pa. The detailed design and the construction status will be described in the paper.

WEPPD066

Design of a Stripline Kicker for Tune Measurement in CSNS RCS

kicker, impedance, cyclotron, wakefield

2675

X.Y. Yang, S. Fu, T.G. Xu
IHEP, Beijing, People's Republic of China

For CSNS RCS tune measurement, tune value is measured by exciting the bunch with strip-line kicker fed with white noise and using FFT algorithm to the turn-by-turn position of the bunch in the BPM. This article simulates the strip-line kicker in RCS and the efficiency of the kicker is discussed in the MATLAB environment. The parameters of the kicker with arc electrode structure such as wake impedance, thermal state and VSWR are analyzed based on the advantage of this design.

WEPPP026

Dielectric-plate-implanted Higher Order Mode (HOM) Waveguide for High Intensity Multi-beam Device Application

HOM, simulation, wakefield, electron

2781

Y.-M. Shin
Fermilab, Batavia, USA

A mode-selective oversized RF-beam channel has been investigated for high intensity multi-beam devices. Implanting the equi-spaced dielectric plates at the transverse positions where longitudinal electric fields of a HOM are minimal in the micro-metallic structure strongly suppresses all lower energy modes and other wakefield modes. The dielectric lattice captures only a single HOM of the wavelengths that correspond to the plate spacing. Electromagnetic simulations have shown that the lower energy modes, TE10 and TE20 modes, are suppressed down to < ~ -60 dB by two plate loads, while TE310-mode prominently propagates through the 2 mm long waveguide only with 4 dB (= -2dB/mm) at 1 THz. The numerical calculation indicated that the TE30 mode has ~ a few times higher Q than the lower energy modes. The strong single mode selectivity has been extensively looked into with a more highly overmoded structure. Feasibility analysis of the HOM structure for multi-beam device application is under investigation. Particle-in-cell (PIC) simulation has shown coherent beam bunching and energy gain from THz driving signal.

WEPPP027

PBG-slab Embedded Traveling Wave Structure for Planar Beam Accelerator Application

electron, HOM, acceleration, photon

2784

Y.-M. Shin
Fermilab, Batavia, USA

The oversized traveling wave (TE10-mode) channel integrated with the photonic-band-gap (PBG) slab arrays have been investigated for planar beam accelerator application. Simulation analysis showed that the slab arrays allow only the PBG-modes (5-6 GHz) to propagate with ~ 2 dB of insertion loss, corresponding to ~ 1.14 dB/cm attenuation, which thereby effectively suppresses trapped non-PBG modes down to ~ -14.3 dB/cm. It will enable monochromatic propagation of fundamental acceleration modes along the heavily over-moded planar waveguide without anomalous excitation of unstable trapped HOMs. The saturated maximum field gradients of the accelerating structure have been analyzed with respect to operational frequency bands corresponding to structural sizes. The field gradient of the guided PBG-mode has been investigated with finite-integral-method (FIM) simulations at W-band. This mode-filter could be utilized for HOM dampers in high aspect ratio (HAR) planar beam accelerators. An experimental test is currently under consideration.

WEPPR004

Effect of Beam-beam Interactions on Stability of Coherent Oscillations in a Muon Collider

collider, luminosity, resonance, quadrupole

2940

K. Ohmi
KEK, Ibaraki, Japan
Y. Alexahin
Fermilab, Batavia, USA

In order to achieve the peak luminosity of a muon collider in the 10³⁵ cm^-2 s^-1 range the number of muons per bunch should be of the order of a few units of 10¹² rendering the beam-beam parameter as high as 0.1 per IP. Such strong beam-beam interaction can be a source of instability if the working point is chosen close to a coherent beam-beam resonance. On the other hand, the beam-beam tune spread can provide a mechanism of suppression of the beam-wall driven instabilities. In this report the coherent instabilities driven by beam-beam and beam-wall interactions are studied with the help of BBSS code for the case of 1.5 TeV c.o.m muon collider.

WEPPR012

Simulating High-Intensity Proton Beams in Nonlinear Lattices with PyORBIT

space-charge, resonance, simulation, proton

2961

S.D. Webb, D.T. Abell, D.L. Bruhwiler, J.R. Cary
Tech-X, Boulder, Colorado, USA
V.V. Danilov, A.P. Shishlo
ORNL, Oak Ridge, Tennessee, USA
S. Nagaitsev, A. Valishev
Fermilab, Batavia, USA

High-intensity proton linacs and storage rings are essential for a) state-of-the-art neutron source user facilities, b) extending the high-energy physics intensity frontier, c) as a driver to generate pions for a future neutrino factory or muon collider, and d) for transmutation of radioactive waste and associated energy production. For example, Project X at Fermilab will deliver MW proton beams at energies ranging from 3 to 120 GeV. Nonlinear magnetic lattices with large tune spreads and with integrable*, nearly integrable** and chaotic* dynamics have been proposed to maximize dynamic aperture and minimize particle loss. We present PyORBIT*** simulations of proton dynamics in such lattices, including the effects of transverse space charge.
* V. Danilov and S. Nagaitsev, PR ST-AB 13 084002 (2010)
** K. Sonnad and J. Cary, Phys. Rev. E 69 056501 (2004)
*** A. Shishlo, J. Holmes and T. Gorlov, From Proceedings of IPAC '09 351-354

WEPPR013

Design of an Electrostatic Extraction Section for the University of Maryland Electron Ring

extraction, simulation, emittance, electron

2964

K.J. Ruisard
Rutgers University, The State University of New Jersey, Piscataway, New Jersey, USA
B.L. Beaudoin, I. Haber, R.A. Kishek, T.W. Koeth
UMD, College Park, Maryland, USA

Funding: This work is supported by the US Dept. of Energy Office of High Energy Physics.
The University of Maryland Electron Ring (UMER) is a 11.5 meter circumference, 10 keV, electron storage ring dedicated to the study of the physics space-charge-dominated beams transported over long path lengths. The intensity of the space charge in UMER can be varied by aperturing the injected beam current from 0.6 mA to 100 mA. Recently, the electron beam has been transported over one thousand turns. To fully characterize the transverse and longitudinal evolution of the beam on a turn-by-turn basis, extraction and transport to a diagnostic station is required. We present the design of a pulsed electric extraction system that satisfies the challenging constraint of fitting the hardware within the dense magnet lattice. The extraction system must universally accommodate the range beam intensities and minimize any disruption to the circulating beam

WEPPR015

Intrabeam Scattering Studies at CesrTA

emittance, scattering, electron, positron

2970

M. P. Ehrlichman
Cornell University, Ithaca, New York, USA
F. Antoniou, Y. Papaphilippou
CERN, Geneva, Switzerland
W. Hartung, M.A. Palmer, D.P. Peterson, N.T. Rider, D. L. Rubin, J.P. Shanks, C.R. Strohman, S. Wang
CLASSE, Ithaca, New York, USA
R. Holtzapple
CalPoly, San Luis Obispo, California, USA

Funding: NSF Award (PHY-0734867) NSF Award (PHY-1002467) Japan/US Cooperation Program Education and lifelong learning, co-financed by Greece and the European Union
Intrabeam scattering dilutes the emittance of low energy, low emittance rings. Because CesrTA can be operated at low energies with low transverse emittances and high bunch intensity, it is an ideal laboratory for the study of IBS effects. Furthermore, CesrTA is instrumented for accurate beam size measurements in all three dimensions, providing the possibility of a complete determination of the intensity dependence of emittances. Models based on classical IBS theories and multi-particle simulations are used to estimate the effect of IBS at CesrTA at different beam emittances, intensities and energies. The first measurements from machine studies at CesrTA are presented.

WEPPR039

Nonlinear Lattice for Space-Charge Dominated Beam Transport with Suppressed Emittance Growth

quadrupole, focusing, space-charge, emittance

3021

Y.K. Batygin, A. Scheinker
LANL, Los Alamos, New Mexico, USA

We present a feasible design for the implementation of a beam emittance growth suppressing lattice for space-charge dominated beams. Our analysis is based on original derivations developed in *. We present a FODO focusing channel with quadrupole and duodecapole components which on average create the ﬁeld required to match the high-brightness beam with the structure. Matched beam exhibits smaller emittance growth than that in regular quadrupole focusing channel. Numerical results demonstrate the lattice’s performance in preventing halo formation of a nonuniform space charge dominated beam.
* Y. Batygin, Phys. Rev. E, 57, 5, p. 6020 (1998).

WEPPR092

Beam Ion Instability in ILC Damping Ring with Multi-gas Species

ion, vacuum, damping, simulation

3150

L. Wang, M.T.F. Pivi
SLAC, Menlo Park, California, USA

Ion induced beam instability is one critical issue for the electron damping ring of the International Linear Collider (ILC) due to its ultra small emittance of 2 pm. The beam ion instability with various beam filling patterns for the latest lattice DTC02 is studied using code IONCLOUD. The code has been benchmarked with SPEAR3 experimental data and there is a good agreement between the simulation and observations. It uses the optics from MAD and can handle arbitrary beam filling pattern and vacuum. Different from previous studies, multi-gas species have been used simultaneously in the simulation. This feature makes it more accurate.

THXB03

Beam and Spin Dynamics in an Electric Proton EDM Ring

proton, dipole, storage-ring, quadrupole

3203

R.M. Talman
CLASSE, Ithaca, New York, USA
J. Talman
BNL, Upton, Long Island, New York, USA

Electric dipole moment (EDM) measurements may help to answer the question ‘‘Why is there more matter than anti-matter in the present universe?'' For a charged baryon like the proton such a measurement is thinkable only in a ring in which a bunch of protons is stored for more than a few minutes, with polarization ‘‘frozen'' (relative to the beam velocity) and with polarization not attenuated by decoherence. Beam and spin dynamics in an all-electric lattice with these characteristics is described. Rings for other charged baryons, such as deuterons or helium-3 nuclei, are also possible but, requiring both electric and magnetic fields, they are more complicated.

Slides THXB03 [0.155 MB]

THPPC039

Study of RF Breakdown in Normal Conducting Cryogenic Structure

cryogenics, impedance, klystron, accelerating-gradient

3368

V.A. Dolgashev, J.R. Lewandowski, D.W. Martin, S.G. Tantawi, S.P. Weathersby, A.D. Yeremian
SLAC, Menlo Park, California, USA

Funding: *Work supported by DoE, Contract No. DE-AC02-76SF00515.
RF Breakdown experiments on short accelerating structures at SLAC have shown that properties of rf breakdown probability are reproducible for structures of the same geometry. At a given rf power and pulse shape, the rf breakdown triggers continuously and independently at a constant average rate. Hypotheses describing the properties of the rf breakdown probabilities involve defects of metal crystal lattices that move under forces caused by rf electric and magnetic fields. The dynamics of the crystal defects depend on the temperature of the structure. To study the dependence we designed and built an experimental setup that includes a cryogenically cooled single-cell, standing-wave accelerating structure. This cavity will be high power tested at the SLAC Accelerator Structure Test Area (ASTA).

THPPD010

Design, Assembly and First Measurements of a Short Model for CLIC Final Focus Hybrid Quadrupole QD0

quadrupole, multipole, magnet-design, permanent-magnet

3515

M. Modena, O. Dunkel, J.G. Perez, C. Petrone, P.A. Thonet, D. Tommasini
CERN, Geneva, Switzerland
E. Solodko, A.S. Vorozhtsov
JINR, Dubna, Moscow Region, Russia

In the framework of the Compact Linear Collider (CLIC) R&D, a tunable hybrid magnet design has been proposed for the final focus QD0 quadrupole. A short model of the magnet has been realized in order to validate the novel design and its expected performances. In order to achieve extremely high quadrupole gradients (>500 T/m), the magnet design combines: a core structure made in magnetic CoFe alloy “Permendur”, permanent magnet blocks, and air-cooled electromagnetic coils. Relevant aspects of this design are the wide tunability of the gradient range, the compactness and the absence of any vibrations. In this paper a reminder of the magnet design concept is given; then, the procurement and assembly main aspects are presented, followed by the results of the magnetic measurements. Finally, some manufacturing considerations relative to a full size magnet procurement are discussed.

THPPD036

High-Field Combined-Function Magnets for a 1.5×1.5 TeV Muon Collider Storage Ring

dipole, quadrupole, collider, magnet-design

3587

V. Kashikhin, Y. Alexahin, N.V. Mokhov, A.V. Zlobin
Fermilab, Batavia, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
A new storage ring lattice based on combined function high-field magnets and conceptual designs of superconducting magnets with dipole and quadrupole coils for a muon collider with a c.o.m. energy of 3 TeV and an average luminosity of 4x10³⁴ cm^-2 s^-1 are presented. Magnets are designed to provide the required focusing field gradient and bending field in the aperture with the appropriate operation margin. Magnets have large apertures to provide an adequate space for internal absorbers, vacuum insulation, beam pipe, and helium channel. Coil cross-sections were optimized to achieve the best possible field quality in the magnet aperture occupied with beams. Magnet parameters are reported and compared with the requirements. Energy deposition calculations with the MARS code have allowed to optimize parameters of inner absorbers and collimators in interconnect regions, thus reducing peak power density and dynamic loads to the tolerable levels.

THPPD054

Low Current Bipolar Magnet Power Supply System at the PLS-II Storage Ring

dipole, quadrupole, EPICS, power-supply

3635

S.-C. Kim, J.Y. Huang, K.R. Kim, S.H. Nam, S. Shin, Y.G. Son, C.W. Sung
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: * This work is supported by the Ministry of Education, Science and Technology, Korea.
Lattice of the Storage Ring (SR) is changed from TDB to DBA, and beam energy is enhanced from 2.5 GeV to 3.0 GeV at the Pohang Light Source upgrade (PLS-II). At the PLS-II, Magnet Power Supplies (MPS) were newly designed according to magnet specification of the PLS-II. All MPSs are adopted switching type power conversion technology. Low current bipolar MPSs for vertical corrector(VC), horizontal corrector(HC), fast corrector(FC), aux.-quadrupole(AQ), skew(SK) and dipole trim coil(TR) magnets are H-bridge type. All MPSs are performed less than ± 10 ppm output current stability and adopted full digital controller. Except vertical corrector MPSs, all unipolar and bipolar MPSs are developed as embedded EPICS IOC. In this paper, we report on the development and characteristics of the bipolar MPS for the PLS-II Storage Ring.

THPPD055

High Current Unipolar Magnet Power Supply System at the PLS-II Storage Ring

power-supply, quadrupole, sextupole, septum

3638

S.-C. Kim, J.Y. Huang, K.R. Kim, S.H. Nam, S. Shin, Y.G. Son, C.W. Sung
PAL, Pohang, Kyungbuk, Republic of Korea

Funding: This work is supported by the Ministry of Education, Science and Technology, Korea.
Lattice of the Storage Ring (SR) is changed from TDB to DBA, and beam energy is enhanced from 2.5 GeV to 3.0 GeV at the Pohang Light Source upgrade (PLS-II). At the PLS-II, Magnet Power Supplies (MPS) were newly designed according to magnet specification of the PLS-II. All MPSs are adopted switching type power conversion technology. High current unipolar MPSs for bending(BD), main-quadrupole(MQ), sextupole(ST) and septum(SP) magnet are parallel operation type of unit stack buck type power supply. Unit stack of unipolar MPS has capability maximum 250A and operation 10kHz. BD and MQ MPS are adopted four stack as each stack 90degree phase shift switching, and have capability maximum 1000 A. ST MPS is adopted two stack as each stack 180degree phase shift switching, and have capability maximum 500 A. SP MPS is adopted single, and have capability maximum 250 A. All unipolar MPSs are developed as full digital controller, embedded EPICS IOC and operated less than ± 10ppm current stability. In this paper, we report on the development and characteristics of the high current unipolar MPS for the PLS-II SR.

THPPP005

Space Charge Effect in the Presence of x-y Coupling in J-PARC MR

coupling, space-charge, emittance, simulation

3731

K. Ohmi
KEK, Ibaraki, Japan
S. Hatakeyama
JAEA/J-PARC, Tokai-mura, Japan

It is crucial issue to suppress beam loss due to space charge force in J-PARC MR. We focus x-y coupling as a source of the beam loss. x-y coupling is measured by turn-by-turn beam position monitors in J-PARC MR. A space charge simulation under the measured x-y coupling evaluates the beam loss. Tolerance of x-y coupling and how to improve the beam loss are discussed.

THPPP024

Alignment and Aperture Scan at the Fermilab Booster

booster, injection, alignment, proton

3785

K. Seiya, J.R. Lackey, W.L. Marsh, W. Pellico, D.A. Still, A.K. Triplett, A.M. Waller
Fermilab, Batavia, USA

The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour, which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be the source of issues. The booster accelerates beam from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the beam is lost within 3 msec after the injection. The aperture at injection energy was measured and compared with the survey data. The magnets are going to be realigned in March 2012 in order to increase the aperture. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves will be discussed in this paper.

THPPP056

Beam Loss Due to Misalignments, RF Jitter and Mismatch in the Fermilab Project-X 3GeV CW Linac

linac, solenoid, quadrupole, beam-losses

3868

J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, J.-F. Ostiguy, A. Saini, B.G. Shteynas, N. Solyak
Fermilab, Batavia, USA

This paper presents an analysis of beam losses along the current design of the FNAL 3 GeV superconducting cw linac. Simulations from the RFQ exit up to the end of the linac (~430 meters) are performed on the FermiGrid using the beam dynamics code TRACK. The impact of beam mismatch, element misalignments, and RF jitter on the beam dynamics is discussed and corresponding beam loss patterns are presented. A correction scheme to compensate for misalignments is described.

THPPP091

Status of the Project-X CW Linac Design

linac, cryomodule, emittance, rfq

3948

J.-F. Ostiguy, P. Berrutti, J.-P. Carneiro, V.A. Lebedev, S. Nagaitsev, A. Saini, B.G. Shteynas, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Superconducting CW linac was proposed for Project X to accelerate H⁻ beam from 2.1 MeV to 3 GeV with nominal peak and average currents of respectively 5 mA and 1 mA. Linac built of 5 different families of resonators: half-wave, spoke (2), and elliptical (2) working at 162.5 MHz 325 MHz and 650 MHz to cover all energy range. Cavities and focusing elements are assembled in cryomodules. In baseline design all cryomodules are separated by short warm sections. It makes machine more reliable and maintainable and provide space for beam diagnostics and collimation. A long (~10m) gap between cryomodules at1 GeV is also being considered to provide space for beam extraction for nuclear experimental program. In paper we present the latest lattice of the linac baseline design and results of beam studies for this lattice. We briefly compare performance of the baseline design with alternative one without half-wave resonator section.

THPPR013

Beam Transport in Alternative Lattices at the University of Maryland Electron Ring (UMER)

quadrupole, injection, focusing, betatron

3993

S. Bernal, B.L. Beaudoin, M. Cornacchia, R.A. Kishek, D.F. Sutter
UMD, College Park, Maryland, USA

Funding: This work is funded by the US Dept. of Energy Offices of High Energy Physics and High Energy Density Physics, and by the US Dept. of Defense Office of Naval Research and Joint Technology Office.
We discuss the motivation, general procedure and results of first experiments of beam transport with two alternative focusing schemes at UMER, a low-energy (10 keV), high-current (1-100 mA) electron storage ring. The new ring optics simplifies injection and RMS envelope matching, and gives us a larger number of beam position monitors (BPMs) per (un-depressed) betatron wavelength, all of which are desirable conditions for better orbit control. Furthermore, one of the new optics schemes is more symmetrical than the standard one, facilitating e.g. the implementation of quadrupole scans for betatron resonance studies. The alternative lattices also allow us to expand significantly on the tune parameter space available for the study of space-charge dominated beam transport.

THPPR018

Development Progress of NSLS-II Accelerator Physics High Level Applications

controls, linac, alignment, EPICS

4005

L. Yang, J. Choi, Y. Hidaka, G. Shen, G.M. Wang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the Department of Energy.
The High Level Applications (HLA) for NSLS-II commissioning is a development in progress. It is in a client-server framework and uses Python programming language for scripting and graphical user interface application development. This new development provides both scripting and graphical user interface (GUI) controls. The services developed in controls group provide name server, archiving, machine snapshot etc. The clients are developed mainly in the physics group and have measurement, analysis and modeling capabilities.

THPPR053

A CW FFAG for Proton Computed Tomography

cyclotron, proton, extraction, acceleration

4094

C. Johnstone, D.V. Neuffer
Fermilab, Batavia, USA
H.L. Owen
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
P. Snopok
IIT, Chicago, Illinois, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
An advantage of the cyclotron in proton therapy is the continuous (CW) beam output which reduces complexity and response time in the dosimetry requirements and beam controls. A CW accelerator requires isochronous particle orbits at all energies through the acceleration cycle and present compact isochronous cyclotrons for proton therapy reach only 250 MeV (kinetic energy) which is required for patient treatment, but low for full Proton Computed Tomography (PCT) capability. PCT specifications need 300-330 MeV in order for protons to transit the human body. Recent innovations in nonscaling FFAG design have achieved isochronous performance in a compact (~3 m radius) design at these higher energies. Preliminary isochronous designs are presented here. Lower energy beams can be efficiently extracted for patient treatment without changes to the acceleration cycle and magnet currents.

THPPR063

1 GeV CW Nonscaling FFAG for ADS, and Magnet Parameters

extraction, cyclotron, simulation, proton

4118

F. Méot, W.-T. Weng
BNL, Upton, Long Island, New York, USA
C. Johnstone
Fermilab, Batavia, USA
P. Snopok
Illinois Institute of Technology, Chicago, IL, USA

Multi-MW proton driver capability remains a challenging, critical technology for many core HEP programs, particularly the neutrino ones such as the Muon Collider and Neutrino factory, and for next generation energy applications such as Accelerator Driven Subcritical Reactors (ADS) and Accelerator Transmutation of Waste for nuclear power and waste management. Work is focused almost exclusively on an SRF linac, as, to date, no re-circulating accelerator can attain the 10^-20 MW capability necessary for the nuclear applications. Recently, the concept of isochronous orbits has been explored and developed for nonscaling FFAGs using powerful new methodologies in FFAG accelerator design. The FFAG can remain isochronous beyond the energy reach of cyclotrons and with fixed magnetic fields and strong focusing coupled to recent advances in tune stability, dynamic aperture, and footprint, serious study is underway on a potential application to the ADS problem. Work is progressing on a stable, high intensity, 0.25-1GeV isochronous FFAG. Development and studies of novel magnets with the nonlinear radial fields required to support isochronous operation are reported here.