IPAC2012 - List of Keywords (optics)

Paper	Title	Other Keywords	Page
MOYCP01	Design and Simulation of IOTA - a Novel Concept of Integrable Optics Test Accelerator	electron, focusing, betatron, simulation	16
	S. Nagaitsev, A. Valishev Fermilab, Batavia, USA V.V. Danilov ORNL, Oak Ridge, Tennessee, USA D.N. Shatilov BINP SB RAS, Novosibirsk, Russia
	The use of nonlinear lattices with large betatron tune spreads can increase instability and space charge thresholds due to improved Landau damping. Unfortunately, the majority of nonlinear accelerator lattices turn out to be nonintegrable, producing chaotic motion and a complex network of stable and unstable resonances. Recent advances in finding the integrable nonlinear accelerator lattices have led to a proposal to construct at Fermilab a test accelerator with strong nonlinear focusing which avoids resonances and chaotic particle motion. This presentation will outline the main challenges, theoretical design solutions and construction status of the Integrable Optics Test Accelerator underway at Fermilab.
	Slides MOYCP01 [2.816 MB]

MOPPC002	Local Chromatic Correction Scheme and Crab-waist Collisions for an Ultra-low β^* at the LHC	sextupole, quadrupole, luminosity, resonance	118
	J.L. Abelleira, S. Russenschuck, R. Tomás, F. Zimmermann CERN, Geneva, Switzerland J.L. Abelleira EPFL, Lausanne, Switzerland C. Milardi, M. Zobov INFN/LNF, Frascati (Roma), Italy K. Ohmi KEK, Ibaraki, Japan D.N. Shatilov BINP SB RAS, Novosibirsk, Russia
	Funding: Work supported by the European Commission under the FP7 Research Infrastructures project Eu- CARD, grant agreement no. 227579. We discuss potential merits and the parameter range of interest for a possible crab-waist collision scheme at the LHC, and report preliminary optics studies of a local chromatic correction scheme with flat beams (β_x^>>β_y^), which could boost the LHC luminosity by about an order of magnitude and would also allow for crab-waist collisions.

MOPPC003	Very Fast LHC Crab Cavity Failures and their Mitigation	luminosity, simulation, betatron, cavity	121
	T. Baer, R. Calaga, R. De Maria, S.D. Fartoukh, E. Jensen, R. Tomás, J. Tückmantel, J. Wenninger, B. Yee-Rendon, F. Zimmermann CERN, Geneva, Switzerland T. Baer University of Hamburg, Hamburg, Germany
	For the high-luminosity LHC upgrade program (HL-LHC), the installation of crab cavities (CCs) is needed to compensate the geometric luminosity loss due to the crossing angle and for luminosity leveling []. The baseline is a local scheme with CCs around the ATLAS and CMS experiments. In a failure case (e.g. a control failure or arcing in the coupler), the voltage and/or phase of a CC can change significantly with a very fast time constant of the order of 1 to 10 LHC turns. This can lead to large, global betatron oscillations of the beam. The impact of CC failures on the beam dynamics is discussed and the results from dedicated simulations are presented. Mitigation strategies to limit the impact of CC failures to an acceptable level are proposed. F. Zimmermann and O. Brüning, “Parameter Space for the LHC High-Luminosity Upgrade”, IPAC'12, MOPPC005, May 2012.

MOPPC005	Parameter Space for the LHC Luminosity Upgrade*	luminosity, target, emittance, brightness	127
	F. Zimmermann, O.S. Brüning CERN, Geneva, Switzerland
	Funding: Work supported by the European Commission under the FP7 Research Infrastructures projects EuCARD, grant agreement no. 227579, and HiLumi LHC, grant agreement no. 284404. We review the parameter space for the high-luminosity upgrade of the LHC (HL-LHC). Starting from the luminosity targets and the primary limitations, e.g., long-range beam-beam effects, event pile up, electron cloud, turnaround time, intrabeam scattering, we determine the range for compatible beam parameters such as the beam intensity, bunch spacing, transverse and longitudinal emittances, bunch length, and IP beta functions required to meet the HL-LHC goals. A selection of a few possible parameter sets is presented for comparison and discussion.

MOPPC006	90m Optics Studies and Operation in the LHC	proton, injection, quadrupole, target	130
	H. Burkhardt, G.J. Müller, S. Redaelli, R. Tomás, G. Vanbavinckhove, J. Wenninger CERN, Geneva, Switzerland S. Cavalier LAL, Orsay, France
	A high β^* = 90 m optics was commissioned and used for first very forward physics operation in the LHC in 2011. The experience gained from working with this optics in 5 studies and operation periods in 2011 was very positive. The target β^* = 90 m was reached by a de-squeeze from the standard 11 m injection and ramp optics on the first attempt and collisions and first physics results obtained in the second study. The optics was measured and corrected with good precision. The running conditions were very clean and allowed for measurements with roman pots very close to the beam.

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

MOPPC008	LHC Optics Determination with Proton Tracks Measured in the Roman Pots Detectors of the TOTEM Experiment	proton, scattering, lattice, 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%.

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

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

MOPPC013	Optics and Lattice Optimizations for the LHC Upgrade Project	luminosity, lattice, 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.

MOPPC016	Combined Ramp and Squeeze at the Large Hadron Collider	injection, quadrupole, collider, dipole	157
	S. Redaelli, M. Lamont, G.J. Müller, R. Tomás, J. Wenninger CERN, Geneva, Switzerland N. Ryckx EPFL, Lausanne, Switzerland
	In the first two years of operation of the CERN Large Hadron Collider (LHC), the betatron squeeze has been carried out at constant flat top energy of 3.5 TeV. Squeeze setting functions are separated from the energy ramp functions. This ensured a maximum flexibility during commissioning because stopping at all intermediate optics for detailed measurements was possible. In order to then improve the efficiency of the operational cycle, combining the ramp and squeeze has been considered. In this paper, the various possibilities for this scheme are reviewed, and proposals of optimized operational cycles with combined ramp and squeeze are presented for different energies. Results of beam tests are also discussed.

MOPPC023	Polarization Transmission at RHIC, Numerical Simulations	polarization, resonance, simulation, proton	178
	F. Méot, M. Bai, C. Liu, M.G. Minty, V.H. Ranjbar BNL, Upton, Long Island, New York, USA
	Ray-tracing methods, using the computer code Zgoubi, have proven efficient for beam and spin dynamics simulations in RHIC (see earlier PAC and IPAC publications). More simulations and results are being produced, including spin code benchmarking and cross-checking, effects of strongest resonances and working point on transport of polarization, polarization with Run 9 and Run 11 measured ramp orbit and optics, polarization profiles, etc. The numerical methods involved are recalled, a status of the work is given.

MOPPC024	Modelling of the AGS Using Zgoubi - Status	simulation, closed-orbit, multipole, coupling	181
	F. Méot, L. A. Ahrens, Y. Dutheil, J.W. Glenn, H. Huang, T. Roser, V. Schoefer, N. Tsoupas BNL, Upton, Long Island, New York, USA
	A computer model, based on the ray-tracing code Zgoubi, is being developed in view of on-line simulation of the RHIC injector AGS, and of beam and spin dynamics simulations and studies in the presence of the cold and warm helical partial snakes. A status of this work is given here.

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

MOPPC045	Scaled Electron Model of a Dogbone Muon RLA with Multi-pass Arcs	linac, electron, quadrupole, dipole	235
	S.A. Bogacz, A. Hutton, G.A. Krafft, V.S. Morozov, Y. Roblin JLAB, Newport News, Virginia, USA K.B. Beard, R.P. Johnson Muons, Inc, Batavia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Supported in part by USDOE STTR Grant DE-FG02-08ER86351. The design of a dogbone RLA with linear-field multi-pass arcs was earlier developed for accelerating muons for a future Neutrino Factory and Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over single pass or pulsed arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme in which a 4.35 MeV/c electron beam is injected in the middle of a 2.9 MeV/pass linac with two double-pass return arcs, and is accelerated to 17.4 MeV/c in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available 1.5 GHz. The footprint of a complete RLA fits in an area of 25 by 7 m. The scheme utilizes only fixed magnetic fields including injection and extraction. The hardware requirements are not very demanding, making it feasible to utilize the existing technologies. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

MOPPC074	Evolution of MAD-X in the Framework of LHC Upgrade Studies	multipole, simulation, luminosity, quadrupole	304
	A. Latina, L. Deniau CERN, Geneva, Switzerland
	The design efforts for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC) will require significant extensions of the MAD-X code widely used for designing and simulating particles accelerators. For this purpose, several new capabilities have been added to the code, namely the possibility to simulate crab cavities for crossing angle compensation, with their imperfections; the selective introduction of thick quadrupole elements for particles tracking, improving the previous implementation entirely based on thin-lenses; and the upgrade of the interface to SixTrack used for distributed tracking with, e.g., LHC@home. These changes are framed into a global redesign of the MAD-X architecture meant to consolidate its structure, improve its performances, and increase its flexibility. Such improvements are described in details in the present paper.

MOPPC083	LinguaFranca - A Graphical User Interface for Accelerator Modeling	simulation, quadrupole, lattice, 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.

MOPPD057	CERN PSB-to-PS Transfer Modifications for the 2 GeV Upgrade	injection, quadrupole, dipole, septum	493
	W. Bartmann, J. Borburgh, S.S. Gilardoni, B. Goddard, A. Newborough, S. Pittet, R. Steerenberg CERN, Geneva, Switzerland C.H. Yu IHEP, Beijing, People's Republic of China
	Within the frame of the CERN PS Booster (PSB) energy upgrade from 1.4 to 2 GeV, the PSB to PS transfer line will be adapted for pulse-to-pulse modulated operation. A modified lattice is presented including a re-design of the switching dipole between ISOLDE and PS and additional collimators to protect the PS injection septum. Optics solutions optimized for small emittance LHC beams as well as for the large emittance high-intensity beams are shown.

MOPPD062	Aperture Measurements in the LHC Interaction Regions	injection, emittance, luminosity, resonance	508
	S. Redaelli, M.C. Alabau Pons, R.W. Assmann, R. Bruce, M. Giovannozzi, G.J. Müller, M. Pojer, J. Wenninger CERN, Geneva, Switzerland
	The aperture of the LHC interaction regions is crucial for the LHC performance because it determines the smaller β^* that can be achieved. The aperture has been measured at a maximum energy of 3.5 TeV and at different β^* values, following optimized procedure to allow safe measurements at high energy. In this paper, the results of these aperture measurements, which are used as a reference for β^* reach and crossing scheme estimates at the LHC interaction points, are presented.

MOPPD071	Error Localization in RHIC by Fitting Difference Orbit	storage-ring, feedback, closed-orbit, dipole	526
	C. Liu, M.G. Minty, V. Ptitsyn 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. Many errors in an accelerator are evidenced as transverse kicks to the beam, which distort the beam trajectory. Therefore, the information of the errors are imprinted in the distorted orbits, which are different from what would be predicted by the optics model. In this paper, we introduce an algorithm for fitting the orbit based on an on-line optics model. We apply the algorithm to localize the location of the elusive source of vertical diurnal variations observed in RHIC, and analyze D0/Dx errors in local coupling measurement.

MOPPD072	A High Energy Collimation System for the European Spallation Source	collimation, target, beam-losses, linac	529
	H.D. Thomsen, A.I.S. Holm, S.P. Møller ISA, Aarhus, Denmark
	At the European Spallation Source (ESS), a ~160 m high energy beam transport (HEBT) system is to guide the high-power (5 MW) proton beam from a superconducting 2.5 GeV linac to a spallation target station. The HEBT could include a single-pass collimation system to protect all downstream accelerator components, including the vital target. The system would be built to withstand both continuous low-power losses (i.e. introduce halo reduction) and infrequent short-term, high-power beam exposure, essentially a fault scenario. Although a collimation system could reduce the uncontrolled beam losses and thus activation levels elsewhere, it takes up precious longitudinal space intended for future beam power upgrades and sets demands for the beam optics, as will be discussed. Possible materials and specifications will also be described.

MOPPD078	Accelerator Physics Study on the Effects from an Asynchronous Beam Dump in the LHC Experimental Region Collimators	proton, simulation, kicker, betatron	547
	L. Lari, R.W. Assmann, V. Boccone, R. Bruce, F. Cerutti, A. Mereghetti, A. Rossi, V. Vlachoudis CERN, Geneva, Switzerland A. Faus-Golfe, L. Lari IFIC, Valencia, Spain
	Funding: This work has been carried out through of the European Coordination for Accelerator Research and Development (EuCARD), co-sponsored by EU 7th Framework Program. Asynchronous beam aborts at the LHC are to be expected once per year. Accelerator physics studies of asynchronous dumps have been performed at different beam energies and beta-stars. The loss patterns are analyzed in order to identify the losses in particular on the Phase 1 Tertiary Collimators (TCT), since their Tungsten jaw insert has a low damage threshold with respect to the loss load expected. Settings for the tilt angle of the TCTs are discussed with the aim of reducing the thermal loads on the TCT themselves.

MOPPP016	Feasibility Study of an ERL-based GeV-scale Multi-turn Light Source	linac, brilliance, undulator, cryomodule	604
	Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko HZB, Berlin, Germany
	A new generation of particle accelerators based on an Energy Recovery Linac (ERL) is a promising tool for a number of new applications. These include high brilliance light sources in a wide range of photon energies, electron cooling of ion beam and ERL-based electron-hadron colliders. Helmholtz-Zentrum Berlin started a feasibility study of GeV-scale multi-turn ERL-based light source (LS). This LS will work in diffraction limited regime in X-rays and with a short length of a light pulse in femtosecond region. The average and peak brightness will be at least an order of magnitude higher than synchrotron-based LS. In this work an overview of the future multi-turn light source is given. Modeling of the Beam Break Up instability is presented.

MOPPR090	Progress Report on Development of a High Resolution Transverse Diagnostic based on Fiber Optics	electron, diagnostics, radiation, photon	996
	R. Tikhoplav, R.B. Agustsson, G. Andonian, A.Y. Murokh, S. Wu RadiaBeam, Santa Monica, USA R.K. Li, P. Musumeci, C.M. Scoby UCLA, Los Angeles, California, USA
	A beam profile monitor utilizing the technological advances in fiber optic manufacturing to obtain micron level resolution is under development at RadiaBeam Technologies. This fiber-optic profiling device would provide a low cost, turn-key solution with nominal operational supervision and requires minimal beamline real estate. Preliminary results of Cherenkov light generation in fiber is presented.

TUYA03	Performance and Prospects of BEPCII	luminosity, coupling, feedback, injection	1030
	Q. Qin IHEP, Beijing, People's Republic of China
	BEPCII, the upgrade project of Beijing Electron Positron Collider (BEPC), has been put into operation for both high energy physics experiments as well as synchrotron radiation application since its completion in 2009. The peak luminosity reaches 6.5*10³² cm^-2 s^-1 at 1.89 GeV with e⁺e⁻ collisions of each beam current 700 mA. The collider operates for dedicated synchrotron radiation mode with 250 mA electron beams at 2.5 GeV. The performance of BEPCII should be reported and the measures to upgrade its luminosity described.
	Slides TUYA03 [5.529 MB]

TUPPC001	Quadrupole Shapes	quadrupole, TRIUMF, controls, multipole	1149
	R.A. Baartman TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	Traditionally, quadrupoles are shaped to have a constant vertical cross-section. In other words, the poles are cylindrical segments extended in the beam direction and circular or hyperbolic in cross section. At the ends, the poles are simply truncated or sometimes slightly smoothed with a chamfer. Even very short quadrupoles are often this shape. A new shape is derived analytically, and it is demonstrated that this shape yields dramatically smaller aberrations.

TUPPC004	Study of a Lattice with a Lower Emittance at SOLEIL	emittance, dipole, lattice, 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.

TUPPC013	Optimization of Lower Emittance Optics for the SPring-8 Storage Ring	emittance, photon, lattice, 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	lattice, sextupole, emittance, resonance	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.

TUPPC017	Orbit and Optics Correction to Realize Designed Machine Performance	emittance, lattice, 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.

TUPPC018	Estimation of Orbit and Optics Distortion of SuperKEKB by Tunnel Deformation	emittance, quadrupole, coupling, luminosity	1197
	A. Morita, H. Koiso, Y. Ohnishi, K. Oide, H. Sugimoto KEK, Ibaraki, Japan
	The tunnel which was used for the KEKB B-factory is reused for the accelerator tunnel of the SuperKEKB. The total vertical displacement of the tunnel subsidence reached almost 30mm during 10 years KEKB operation. In order to operate the SuperKEKB which might be more delicate machine than the previous KEKB B-factory, we are evaluating the optics distortion by the tunnel deformation and studying the machine performance after the orbit and optics correction. We report the estimation of the machine performance degradation by the tunnel subsidence and the requirement of the correction.

TUPPC020	A Scheme for Horizontal-vertical Coupling Correction at SuperKEKB	coupling, simulation, lattice, 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	lattice, 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.

TUPPC034	Preparation of SLS for IBS Measurements	emittance, diagnostics, impedance, radiation	1233
	N. Milas, M. Böge, A. Streun PSI, Villigen, Switzerland M. Aiba, A. Lüdeke, A. Saa Hernandez Paul Scherrer Institut, Villigen, Switzerland F. Antoniou, Y. Papaphilippou CERN, Geneva, Switzerland
	It is planned to use the SLS for testing damping ring issues related to linear colliders. One aspect is the study of Intra-Beam Scattering (IBS) effects, which are a limiting factor for ultra-low emittance rings. In this paper we present the setup and characterization of a new mode of operation in which the SLS runs at lower energy (1.57 GeV) with a natural emittance of 2.4 nm rad. This is much smaller than that at the nominal energy (2.41 GeV) and should make IBS effects more easily visible. In order to be able to observe IBS a careful setup is required: Optics measurement and correction as well as measurements of the bunch natural energy spread and the onset of turbulent bunch lengthening. Also, a detailed discussion on the available diagnostics and their limitations are shown and finally some preliminary results of beam emittance measurements, in all three planes, as a function of single bunch current are presented.

TUPPC036	Integration with the LHC of Electron Interaction Region Optics for a Ring-ring LHeC	quadrupole, proton, dipole, electron	1239
	L.N.S. Thompson Cockcroft Institute, Warrington, Cheshire, United Kingdom R. Appleby UMAN, Manchester, United Kingdom N.R. Bernard ETH, Zurich, Switzerland H. Burkhardt, B.J. Holzer CERN, Geneva, Switzerland M. Fitterer KIT, Karlsruhe, Germany M. Klein The University of Liverpool, Liverpool, United Kingdom P. Kostka DESY Zeuthen, Zeuthen, Germany
	The Large Hadron Electron Collider (LHeC) project is a proposal to study e-p and e-A interactions at the LHC. One design uses an electron synchrotron to collide a 60GeV e± beam with the 7TeV proton beam. Designing a new accelerator around the existing LHC machine poses unique challenges, particularly in the interaction region (IR). The electron beam must be quickly separated from the proton beam after the interaction point (IP) to avoid beam-beam effects, while not significantly reducing luminosity or producing large amounts of synchrotron radiation. The proton beam must pass through the electron optics, while the electron beam must avoid the proton optics. The long straight section requires bending in both planes to counteract the IP crossing angle and to displace the beam vertically from the electron machine to the proton IP. An achromatic bending scheme is used in the vertical plane to eliminate dispersion at the IP and provide an optics which is well matched to the LHeC ring lattice. The interaction region and long straight section design is presented and detailed, and the design process and principles discussed.

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

TUPPC038	Interaction Region Optics for the Non-Interacting LHC Proton Beam at the LHeC	proton, electron, quadrupole, synchrotron	1245
	L.N.S. Thompson Cockcroft Institute, Warrington, Cheshire, United Kingdom R. Appleby UMAN, Manchester, United Kingdom O.S. Brüning, B.J. Holzer CERN, Geneva, Switzerland M. Klein The University of Liverpool, Liverpool, United Kingdom P. Kostka DESY Zeuthen, Zeuthen, Germany
	The Large Hadron Electron Collider project is a proposal to study e-p and e-A interactions at the LHC. Two electron accelerator designs are being studied; a linac and a synchrotron. In the synchrotron option, a 60GeV electron beam is collided with one of the LHC proton beams to provide high luminosity TeV-scale interactions. The interaction region for this scheme is complex and introduces a series of challenges due to the integration of the two machines. One of these is the optics of the second non-interacting proton beam. The second proton beam must not interfere with the LHeC experiment, but simultaneous running of the remaining LHC experiments requires that this beam must still circulate relatively undisturbed. This paper discusses methods to solve these challenges for the electron synchrotron design.

TUPPC040	Model Calibration and Optics Correction Using Orbit Response Matrix in the Fermilab Booster	booster, dipole, acceleration, coupling	1251
	M.J. McAteer, S.E. Kopp The University of Texas at Austin, Austin, Texas, USA V.A. Lebedev, E. Prebys Fermilab, Batavia, USA A.V. Petrenko BINP SB RAS, Novosibirsk, Russia
	A beam-based method of optical model calibration using the measured orbit response matrix, known as the LOCO method, was successfully applied to Fermilab's rapid-cycling Booster synchrotron. Orbit responses were measured by individually changing the strength of each dipole corrector throughout the acceleration cycle, and dispersion was measured by changing the beam's radial offset. The model calibration procedure revealed large calibration errors for all elements in the Booster's recently-installed multipole corrector packages and beam position monitors. The resulting model was used to correct coupling and beta beating.

TUPPC043	Design of Accumulator and Compressor Rings for the Project-X Based Proton Driver	lattice, proton, linac, 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.

TUPPC044	Emittance and Phase Space Tomography for the Fermilab Linac	emittance, linac, focusing, quadrupole	1263
	C. Johnstone, F.G.G. Garcia, T. Kobilarcik, G.M. Koizumi, C.D. Moore, D.L. Newhart Fermilab, Batavia, USA
	Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Dept. of Energy. The Fermilab Linac delivers a variable intensity, 400-MeV beam to the The MuCool Test Area experimental hall via a beam line specifically designed to facilitate measurements of the Linac beam emittance and properties. A 10 m, dispersion-free and magnet-free straight utilizes an upstream quadrupole focusing triplet in combination with the necessary in-straight beam diagnostics to fully characterize the transverse beam properties. Since the Linac does not produce a strictly elliptical phase space, tomography must be performed on the profile data to retrieve the actual particle distribution in phase space. This is achieved by rotating the phase space distribution using different waist focusing conditions of the upstream triplet and performing a de-convolution of the profile data. Preliminary measurements using this diagnostic section are reported here.

TUPPC046	Further Analysis of Real Beam Line Optics from a Synthetic Beam	coupling, linac, closed-orbit, electron	1269
	R.M. Bodenstein UVa, Charlottesville, Virginia, USA Y. Roblin, M.G. Tiefenback JLAB, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a license to publish or reproduce this manuscript for U.S. Government purposes. Standard closed-orbit techniques for Twiss parameter measurement are not applicable to the open-ended Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. The evolution of selected sets of real orbits in the accelerator models the behavior of a “synthetic” beam. This process will be validated against beam profile-based Twiss parameter measurements and should provide the distributed optical information needed to optimize beamline tuning for an open-ended system. This work will discuss the current and future states of this technique, as well as an example of its use in the CEBAF machine.

TUPPC053	Longitudinal Tuning of the SNS Superconducting Linac	cavity, linac, acceleration, controls	1290
	T.V. Gorlov ORNL, Oak Ridge, Tennessee, USA
	Funding: This work was supported by SNS through UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 for the U.S. Department of Energy. The SNS superconducting linac delivers proton beam with about 1 GeV of energy driven by self-consistent RF cavities. Here, we present an experience of the longitudinal tune-up of the SNS superconducting linac where a new application for quick RF phase setup and cavity fault adaptation was created. The routine of superconducting linac tune-up, longitudinal beam manipulation, and radio frequency cavity phase scaling for beam state recovery is presented. The application has direct value for beam optics study and will serve as the basis for longitudinal beam-size manipulation for a laser stripping project.

TUPPC056	Optics Measurements and Corrections at RHIC	quadrupole, proton, luminosity, lattice	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.

TUPPC060	Beam Optics and the pp2pp Setup of the STAR Experiment at RHIC	quadrupole, proton, simulation, scattering	1311
	P.H. Pile, W. Guryn, J.H. Lee, S. Tepikian, K. Yip 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. The newly installed forward detector system at the STAR experiment at RHIC measures small angle elastic and inelastic scattering of polarized protons on polarized protons. The detector system makes use of a pair of Roman Pot (RP) detectors, instrumented with silicon detectors, and located on either side of the STAR intersection region downstream of the DX and D0 dipoles and quadrupole triplets. The parallel to point optics is designed so that scattering angles are determined from position measurements at the RP's with small error. The RP setup allows measurement of position and angle for a subset of the scattered protons. These measured position/angle correlations at the RP's can be compared with optics model predictions to get a measure of the accuracy of the quadrupole triplet current settings. The current in each quadrupole in the triplets is comprised of sums and differences of up to six power supplies and an overall 1% error in the triplet field strengths results in a 4% error in four-momentum transfer squared. This technique is also useful to check the polarity of the skew elements located in each quadrupole triplet. Results of the analysis will be presented.

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

TUPPC063	The AGS Synchrotron with Four Helical Magnets	injection, resonance, betatron, quadrupole	1320
	N. Tsoupas, H. Huang, W.W. MacKay, T. Roser, D. Trbojevic BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the US Department of Energy. The idea of using two partial helical magnets was applied successfully to the AGS synchrotron, to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. This modification provides many advantages over the present setup of the AGS that uses two partial helical magnets. First, the symmetric placement of the four helical magnets allows for a better control of the AGS optics with reduced values of the beta functions especially near beam injection, second, the vertical spin direction during beam injection and extraction is closer to vertical, and third, it provides a larger “spin tune gap” for the placement of both the vertical and horizontal tunes of the AGS during acceleration, second. Although the same spin gap can be obtained with two partial helices of equal strength, the required strength of the two helices makes it impractical. In this paper we will provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and comparison of these results with the present setup of the AGS that uses two partial helical magnets. T. Roser et al., Proc. EPAC04, p. 1577 (2004). H. Huang et al., PRL 99, 154801(2007). * N. Tsoupas et. al., these proceedings.

TUPPC071	Comparison of Different Numerical Modelling Methods for Beam Dynamics in Electrostatic Rings	simulation, lattice, quadrupole, 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.

TUPPC079	Tracking LHC Models with Thick Lens Quadrupoles: Results and Comparisons with the Standard Thin Lens Tracking	quadrupole, lattice, simulation, 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.

TUPPC090	Beam Physics of Integrable Optics Test Accelerator at Fermilab	simulation, betatron, resonance, lattice	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.

TUPPC096	Optimization of the Dynamic Aperture for SPEAR3 Low-emittance Upgrade	sextupole, emittance, resonance, dynamic-aperture	1380
	L. Wang, X. Huang, Y. Nosochkov, J.A. Safranek SLAC, Menlo Park, California, USA M. Borland ANL, Argonne, USA
	A low emittance upgrade is planned for SPEAR3. As the first phase, the emittance is reduced from 10nm to 7nm without addition magnets. A further upgrade with even lower emittance will require a damping wiggler. There is a smaller dynamic aperture for the lower emittance optics due to the stronger nonlinearity. A Multi-Objective Genetic Optimization (MOGA) code is used to maximize the dynamic aperture. Both the dynamic aperture and beam lifetime are optimized simultaneously. Various configurations of the sextupole magnets have been studied in order to find the best configuration. The betatron tune also can be optimized to minimize resonance effects. The optimized dynamic aperture increases 15% from the normal case and the life time increases from 15 hours to 17 hours. It is important that the increase of the dynamic aperture is mainly in the beam injection direction. Therefore the injection efficiency will benefit from this improvement.

TUPPD016	Collection Optics with the Horn Type Focusing Element made with Separate Conductors	focusing, positron, secondary-beams, scattering	1443
	A.A. Mikhailichenko CLASSE, Ithaca, New York, USA
	We describe the device for focusing of charged particles by the system of separated conductors which follow the parabolic profile. Basically this is a horn-type focuser, but with the individual conductors instead of continuous surface. This device allows substantial reduction of fabrication cost with the same focusing properties as the continuous parabolic surface. We recommend this “bird-cage” type system for focusing pions/muons in the projects under discussion in many Laboratories around the World.

TUPPD031	Novel Techniques for Isotope Harvesting at FRIB	simulation, ion, target, resonance	1470
	M.A.C. Cummings Muons, Inc, Batavia, USA L.L. Bandura FRIB, East Lansing, Michigan, USA
	Exotic isotopes have applications in medicine, industry, and national security. Historically, the U.S. has relied on foreign sources for these isotopes. FRIB will be a domestic source of these isotopes. While FRIB is mainly focused on producing exotic isotopes for basic nuclear physics experiments, it also offers an opportunity to harvest unused isotopes for other applications. It is critical that isotope harvesting take place in a synergistic manner that does not adversely affect experiments that will be simultaneously taking place at the facility. Beam optics schemes will be calculated to determine the best locations and methods of separation. These calculations will use COSY Monte Carlo and G4beamline in conjunction with other state of the art ion optical codes that simulate isotope dynamics in magnetic fields and in matter. The results of these simulations will be used to determine the best beam-target combinations to produce the isotopes that are most in-demand and calculate purities of these isotopes in multiple locations in the fragment separators. Trapping and extraction schemes will also be described to maximally recover pure isotope samples.

TUPPP001	Beam Based Measurements with Superconducting Wigglers at the Canadian Light Source with Applications to Nonlinear Beam Dynamics	wiggler, injection, dynamic-aperture, multipole	1599
	W.A. Wurtz, L.O. Dallin, M.J. Sigrist CLS, Saskatoon, Saskatchewan, Canada
	The Canadian Light Source (CLS) employs two superconducting wigglers for the production of hard x-rays. These wigglers cause a large decrease in injection efficiency. While such a decrease is not unexpected due to the large distortion to the linear optics, a correction to the linear optics does not restore injection efficiency. This inability to restore injection is not predicted by a kickmap model of the wiggler. We performed beam based measurements to construct a phenomenological, nonlinear model of the wiggler. Particle tracking with this wiggler model shows that the reduction in dynamic aperture is due to the amplitude dependent tune shift crossing a resonance, even with the linear optics corrected. Moving the tunes allows us to avoid this resonance and measurements at these tunes show that injection efficiency is not greatly affected by the wigglers.

TUPPP004	Low-alpha Operation for the SOLEIL Storage Ring	injection, coupling, radiation, photon	1608
	M.-A. Tordeux, J. Barros, A. Bence, P. Brunelle, N. Hubert, M. Labat, P. Lebasque, A. Nadji, L.S. Nadolski, J.-P. Pollina SOLEIL, Gif-sur-Yvette, France C. Evain PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France
	The low momentum compaction factor (alpha) operation has been recently established on the SOLEIL Storage Ring. Both time resolved X-ray and THz radiation user communities are taking benefit from a hybrid filling pattern with a 4.7 ps RMS bunch length. At a value of 1.7 10^-5 (nominal alpha /25) and a current per bunch of 65 μA, stable THz radiation is produced in the range of 8 - 20 cm^-1 (measurements and comparison with Coherent Synchrotron Radiation (CSR) modeling are reported elsewhere, ). Several low-alpha optics have been investigated and the optics presented at IPAC’11 has been selected for the operation. This paper presents the comprehensive experimental characterization of this optics. Specificities of the low-alpha operation, driven by the very demanding user experiments, are reviewed: closed orbit stability issues, extremely tight injected current step when refilling which implies a specific Linac tuning, low current diagnostics optimization, short bunch measurements, insertion devices effect on the CSR characteristics and radiation safety aspects justified by beam losses at injection. C. Evain, A. Loulergue et al., this conference. ** E. Roussel et al., this conference.

TUPPP007	Modifications to the Machine Optics of BESSY II Necessitated by the EMIL Project	undulator, cryogenics, dipole, storage-ring	1614
	P.O. Schmid, J. Bahrdt, T. Birke, R. Follath, P. Kuske, D. Simmering, G. Wüstefeld HZB, Berlin, Germany
	The Helmholtz Zentrum Berlin and the Max Planck Society are going to build a new dedicated X-ray beam line at the synchrotron source light source BESSY II which will be used for analyzing materials for renewable energy generation. The new large scale project has been dubbed EMIL. In this document we present the modifications to the machine optics and to what extent these changes affect the performance of BESSY II.

TUPPP010	Spectral and Temporal Observations of CSR at ANKA	radiation, synchrotron, storage-ring, synchrotron-radiation	1623
	V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schuh, M. Schwarz, N.J. Smale, M. Streichert KIT, Karlsruhe, Germany M.J. Nasse Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. ANKA is a synchrotron light source situated at the Karlsruhe Institute of Technology. Using dedicated low-α-optics at ANKA we can reduce the bunch length and generate Coherent Synchrotron Radiation (CSR). Studies of the coherent emission in the time domain allow us to gain an insight into the longitudinal bunch dynamics. These as well as the systematic investigations of the THz spectrum range can be used for benchmarking of theoretical predictions. In this paper we report about the recent progress in CSR observation using fast THz detectors and a Martin-Puplett spectrometer at the ANKA storage ring.

TUPPP011	Simulations of Fringe Fields and Multipoles for the ANKA Storage Ring Bending Magnets	multipole, simulation, sextupole, storage-ring	1626
	M. Streichert, M.J. Nasse Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany V. Afonso Rodriguez, A. Bernhard, N. Hiller, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schwarz, N.J. Smale KIT, Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. ANKA is the synchrotron light source of the Karlsruhe Institute of Technology (KIT). With a maximum particle energy of 2.5 GeV, the storage ring lattice consists of 16 bending magnets with a nominal magnetic flux density of 1.5 T. For the beam dynamics simulations the consideration of the fringe fields and multipoles is essential. A reference measurement of the longitudinal magnetic flux density profile of a bending magnet exists for a current of 650 A, corresponding to a particle energy of 2.46 GeV. For lower beam energies where the magnets are no longer close to saturation, however, the exact density profiles may vary significantly. In order to derive fringe fields and multipole components for different beam energies, simulations of the magnetic flux density for different beam energies were conducted using a finite element method (FEM). We present the results of the simulations and demonstrate the improvements of the beam dynamics simulations in AT (Accelerator Toolbox).

TUPPP015	Status and Recent Progress of SPring-8	coupling, emittance, lattice, storage-ring	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	lattice, emittance, photon, dipole	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, injection, storage-ring, lattice	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, lattice, 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.

TUPPP034	BPM Gains and Beta Function Measurement Using MIA and FPGA BPMs at the APS	betatron, lattice, 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.

TUPPP065	Progress Report on the SwissFEL Injector Test Facility	emittance, quadrupole, laser, dipole	1747
	T. Schietinger, M. Aiba, S. Bettoni, B. Beutner, M. Csatari, K. Doshekenov, Y.-C. Du, M.W. Guetg, C.P. Hauri, R. Ischebeck, F. Le Pimpec, N. Milas, G.L. Orlandi, M. Pedrozzi, P. Peier, E. Prat, S. Reiche, B. Smit, A. Trisorio, C. Vicario Paul Scherrer Institut, Villigen, Switzerland
	The SwissFEL injector test facility at the Paul Scherrer Institute is the principal test bed and demonstration plant for the SwissFEL project, which aims at realizing a hard-X-ray Free Electron Laser by 2017. The RF photoinjector facility has been in operation since 2010 and has recently reached its design energy of 250 MeV. A newly installed movable magnetic chicane allows longitudinal bunch compression studies. We report on the first experience with the bunch compressor and present the latest results of projected and slice emittance measurements.
	Poster TUPPP065 [1.801 MB]

TUPPR029	Performance of Linear Collider Beam-Based Alignment Algorithms at FACET	linac, alignment, simulation, emittance	1879
	A. Latina, J. Pfingstner, D. Schulte CERN, Geneva, Switzerland E. Adli University of Oslo, Oslo, Norway
	The performance of future linear colliders will depend critically on beam-based alignment (BBA) and feedback systems, which will play a crucial role both in the linear and in the non-linear systems of such machines, e.g., the linac and the final-focus. Due to its characteristics, FACET is an ideal test-bench for BBA algorithms and linear collider beam-dynamics in general. We present the results of extensive computer simulations and their experimental verification.

TUPPR035	A Comparative Study for the CLIC Drive Beam Decelerator Optics	quadrupole, injection, alignment, lattice	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.

TUPPR043	New Baseline Design of the ILC RTML System	positron, electron, linac, damping	1915
	N. Solyak, V.V. Kapin, A. Vivoli Fermilab, Batavia, USA S. Seletskiy BNL, Upton, Long Island, New York, USA
	The new ILC baseline was proposed in 2009 (Strawman baseline - SB2009) to minimize cost of the machine and accommodate many changes made in the design of the accelerator systems. The biggest changes are made in the central area, where BDS, RTML, DR, electron and positron sources are sharing the tunnels. A new layout of the compact DR and re-location of the electron and positron sources to the main tunnel requires a new lattice design for all beamlines in this area. The lattice design was coordinated between accelerator systems and Convention Facility and Siting (CFS) group to eliminate conflicts between beamlines and satisfy construction requirements. In this paper we present a new design of the RTML electron and positron lattices in the central area and other modifications made in the RTML line to accommodate changes to the beamline layouts.

TUPPR056	Parametric Study of the CLIC Damping Rings Delay Ring for Reaching Isochronicity Conditions	dipole, sextupole, damping, quadrupole	1948
	P. Zisopoulos, F. Antoniou, Y. Papaphilippou CERN, Geneva, Switzerland
	A delay ring in the CLIC damping rings complex is necessary for recombining the two trains to one with the nominal bunch separation of 0.5ns. The preservation of the longitudinal bunch distribution demands an optics design, which eliminates momentum compaction factor up to high order, allowing the delay ring to function under isochronous conditions. Taking into account thin lens approximation, a qualitative estimation of parameters of the cell that will be used in the delay ring, is given, so as to obtain isochronicity conditions. Considerations on the possibility of tuning the cell under those requirements are finally presented.

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

TUPPR077	Simulation Studies for the LHC Long-Range Beam-Beam Compensators	simulation, resonance, collider, betatron	2002
	T.L. Rijoff, R.J. Steinhagen, F. Zimmermann CERN, Geneva, Switzerland
	The LHC performance and the minimum crossing angle are limited by long-range beam-beam collisions. Wire compensators can mitigate part of the long-range effects and may allow for smaller crossing angles, smaller β^*, or higher beam intensity. A prototype long-range wire compensator should be installed in the LHC by 2014/15. We report simulation studies examining and comparing the efficiency of the wire compensation, in terms of tune footprint or dynamic aperture, at various candidate locations, with different wire shapes, and for varying transverse distance from the beam.

TUPPR080	Integration of Detector into Interaction Region at MEIC	ion, dipole, solenoid, electron	2011
	V.S. Morozov, R. Ent, P. Nadel-Turonski JLAB, Newport News, Virginia, USA C. Hyde Old Dominion University, Norfolk, Virginia, USA
	Funding: Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation facility for the study of strong interaction (QCD). Accessing the relevant physics requires a full-acceptance detector with a dedicated small-angle high-resolution detection system capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the original ion beam. We present a design of such a detection system integrated into the collider's interaction region, in which full acceptance is attained by letting small-angle collision products pass through the nearest elements of the machine final-focusing system for further detection. The proposed design is consistent with the current collider optics and demonstrates an excellent performance in terms of detector acceptance and resolution. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

TUPPR089	Design Study of Beam Injection for SuperKEKB Main Ring	injection, septum, synchrotron, emittance	2035
	T. Mori, N. Iida, M. Kikuchi, T. Mimashi, Y. Sakamoto, H. Sugimoto, S. Takasaki, M. Tawada KEK, Ibaraki, Japan
	The SuperKEKB project is in progress toward the initial physics run in the year 2015. It assumes the nano-beam scheme, in which the emittance of the colliding beams is ε=4.6 nm. The emittance of the injected beam is ε=1.46 nm. To achieve such a low emittance, it is vitally important to preserve the emittance during the transport of the beam from the linac to the main ring. One of the most difficult parts is the injection system. We are considering the synchrotron injection for the electron-line to avoid a beam blowup in the ring after injection, which is caused by a beam-beam interaction with the stored beam. The optics study for electron injection and the current R&D status for the septum magnet will be reported in this paper.

WEEPPB014	The Magnetic Model of the LHC during the 3.5 TeV Run	quadrupole, injection, dipole, controls	2194
	E. Todesco, N. Aquilina, M. Giovannozzi, M. Lamont, F. Schmidt, R.J. Steinhagen, M. Strzelczyk, R. Tomás CERN, Geneva, Switzerland N.J. Sammut University of Malta, Information and Communication Technology, Msida, Malta
	The magnetic model of the LHC is based on a fit of the magnetic measurements through equations that model the field components (geometric, saturation, persistent) at different currents. In this paper we will review the main results related to the magnetic model during the run of the LHC in 2010-2011: with a top energy of 3.5 TeV, all components of the model but the saturation are visible. We first give an estimate of the reproducibility of the main components and multipolar errors as they can be deduced from beam measurements, i.e. orbit, tune, chromaticity, beta beating and coupling. We then review the main results relative to the decay at injection plateau, dependence on powering history, and snapback at the beginning of the ramp for both tune and chromaticity. We discuss the precision obtained in tracking the magnets during the ramp, where the persistent current components gradually disappear. We conclude by presenting the behaviour of the quadrupoles model during the squeeze. A list of the major changes implemented during the operation together with what are considered as the main open issues is given.

WEPPD049	Characterization of the Engineered Photodiode-based Fiber Link Stabilization Scheme for Optical Synchronization Systems	laser, LLRF, FEL, controls	2627
	T. Lamb, M.K. Bock, M. Felber, F. Ludwig, H. Schlarb, S. Schulz DESY, Hamburg, Germany S. Jabłoński Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	Pulsed optical synchronization systems are used in modern FELs like FLASH and will be used in the upcoming European XFEL. Their purpose is to distribute synchronization signals with femtosecond stability throughout the machine. Optical fibers are used to transport the pulses carrying the timing information to their end-stations. These fibers have to be continuously delay stabilized in order to achieve the desired precision. In this paper, a photodiode-based detector to measure the drifts of the fiber delay and allows their active correction is presented. Promising results from a first prototype setup of a photodiode-stabilized optical fiber link were the starting point for an engineering of this concept. An enclosure with free-space optics, fiber optics and integrated electronics for the detector, operating at 9.75 GHz, was designed. This unit includes all required parts to stabilize four fiber links. It allows to investigate the temperature sensitivity of the detector. Furthermore, results from drift measurements carried out with a two channel engineered detector are presented in this paper.

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

WEPPP060	A Robust Transverse Feedback System	feedback, kicker, status, pick-up	2843
	M. Alhumaidi, A.M. Zoubir TU Darmstadt, Darmstadt, Germany
	Transverse feedback systems use pickups signals to measure the beam instabilities and kickers to correct the beam. The correction signal is calculated according to the transfer matrices between the pickups and the kickers. However, errors due to magnetic field imperfections and magnets misalignments lead to deviations in the transfer matrices from their nominal values, which affects the feedback quality in a negative manner. In this work we address a new concept for robust feedback system against optics errors or uncertainties. A kicker and multiple pickups are used for each transversal direction. We introduce perturbation terms to the transfer matrices between the kicker and the pickups. Consequently, the Extended Kalman Filter is used to estimate the feedback signal and the perturbation terms by means of the measurements from the pickups. Finally results for the heavy ions synchrotron SIS 18 at the GSI are shown.

WEPPR072	Increasing Instability Thresholds in the SPS by Lowering Transition Energy	emittance, injection, extraction, coupling	3096
	H. Bartosik, G. Arduini, T. Argyropoulos, T. Bohl, S. Cettour-Cave, K. Cornelis, J. Esteban Muller, W. Höfle, Y. Papaphilippou, G. Rumolo, B. Salvant, E.N. Shaposhnikova CERN, Geneva, Switzerland
	A new optics for the SPS with lower transition energy was tested experimentally during 2010-2011, showing a significant increase of the single bunch instability thresholds at injection, due to the 3-fold increase of the slip factor. This paper summarizes the series of performed machine studies for different LHC bunch structures and intensities. In particular, the search of the TMCI threshold in the new optics is presented. Observations on the longitudinal multi-bunch stability are compared between the nominal and the low-transition optics. Finally, optics variants with higher vertical tunes are discussed, which can allow to further increase the TMCI and vertical instability thresholds by reducing the vertical beta function.

WEPPR079	Observations of Microbunching Instabilities from a THz Port at Diamond Light Source	radiation, storage-ring, synchrotron, electron	3114
	W. Shields, G.E. Boorman, V. Karataev, A. Lyapin JAI, Egham, Surrey, United Kingdom R. Bartolini, A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom
	Diamond Light source is a third generation synchrotron facility dedicated to producing radiation of outstanding brightness. Above a threshold current, the electron bunches are susceptible to the phenomenon known as the microbunching instability. This instability is characterised by the onset of radiation bursts, the wavelength of which is around one order of magnitude shorter than the bunch length. Near threshold, the bursting occurs quasi-‐periodically, however at higher currents, the bursting appears randomly. The high frequencies involved in these emissions make detection and analysis challenging. A port specifically for the investigation of mm wave emissions has recently been built at Diamond. Ultra fast Schottky Barrier Diode detectors have been installed to obtain data for only a small fraction of the bunch revolution time in an updated data acquisition system. The threshold current and subsequent evolution of the instability have been investigated.

THPPD023	Solenoid Field Calculation of the SuperKEKB Interaction Region	solenoid, quadrupole, interaction-region, superconducting-magnet	3548
	N. Ohuchi, Y. Arimoto, M. Iwasaki, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, M. Tawada, K. Tsuchiya, H. Yamaoka KEK, Ibaraki, Japan
	The SuperKEKB is the electron-positron collider, and the target luminosity is 8×10³⁵ cm^-2s⁻¹, which is 40 times larger than the attained luminosity of KEKB. The beam final focus system consists of many types of superconducting magnets as 8 quadrupoles, 40 correctors and 4 compensation solenoids. These focusing magnets and correctors are designed to be operated inside the particle detector, Belle, and under the solenoid field of 1.5 T. From the analysis of beam optics, the solenoid field profile has serious impact on the beam vertical emittance. We designs the solenoid field profile along the Belle axis in a 2-dimensional model as the first step, and now we developed this model to the 3-dimensional calculation in detail. The solenoid field profiles along the both beam lines are generated with the combine solenoid field by the Belle solenoid and the compensation solenoids, and the magnetic components of the magnets and the magnetic shields on the beam lines. The model is very complicate. From the calculation results, we will discuss the influence on the beam optics and the final focusing magnet system.

THPPP030	Near Integer Tune for Polarization Preservation in the AGS	polarization, acceleration, injection, resonance	3797
	N. Tsoupas, L. A. Ahrens, M. Bai, K.A. Brown, J.W. Glenn, H. Huang, W.W. MacKay, T. Roser, V. Schoefer, K. Zeno BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the US Department of Energy. The high energy (T=250 GeV) polarized proton beam experiments performed in RHIC, require high polarization of the beam. In order to preserve the polarization of the proton beam, during the acceleration in the AGS, which is the pre-injector to RHIC, two partial helical magnets have been installed in AGS. In order to minimize the loss of the beam polarization due to the various intrinsic spin resonances occurring during the proton acceleration, we constrain the value of the vertical tune to be higher than 8.97. With the AGS running at near integer tune the perturbations caused by the partial helical magnets is large resulting in large beta and dispersion waves. To mitigate the adverse effect of the partial helices on the optics of the AGS, we have introduced compensation quads** in AGS. In this paper we present the beam optics of the AGS which ameliorates this effect of the partial helices. * H. Huang, et al., Proc. EPAC06, p. 273, (2006). ** N. Tsoupas et al., Proc. PAC07, p. 3723 (2007).

THPPR001	Setting Generation for FAIR	controls, synchrotron, storage-ring, proton	3963
	D. Ondreka, J. Fitzek, H. Liebermann, R. Müller GSI, Darmstadt, Germany
	The experimental program envisaged for the Facility for Antiproton and Ion Research (FAIR) requires complex operation schemes of its accelerators and beamlines including parallel operation of several experiments. Thus, there is a strong need to develop an appropriate setting generation system, which shall supply consistent settings for all devices across the facility to support the planned parallel operation modes. This system should also provide standard tools for modifying and accessing the settings. These requirements will be met by using LSA, a generic accelerator modeling framework developed at CERN, as basis for the setting generation system. We will report on the status of the setting generation system for FAIR, covering both the implementation of the physics model as well as the extensions to the LSA framework realized within a collaboration with CERN. Results of the first test runs with the existing GSI synchrotron SIS18 will be presented.

THPPR014	FRIB High-level Software Architecture	controls, EPICS, monitoring, feedback	3996
	P. Chu, T.D. Brown, R. Gaul, S. Peng FRIB, East Lansing, Michigan, USA E.T. Berryman, V. Vuppala NSCL, East Lansing, Michigan, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 The Facility for Rare Isotope Beams (FRIB) is setting up its high-level application software architecture. The architecture is based on Service Oriented Architecture, and consists of back-end data storage, client/service infrastructure, control system connectivity, supporting libraries and front-end Graphical User Interface (GUI). The architecture provides online models of FRIB as a service and allows for storage of both structured and non-structured data. The model for structured data is implemented using the Integrated Relational Model of Installed Systems (IRMIS). The GUI is based on Control System Studio (CSS) framework. Libraries, service, data access and GUI tools will be available as Application Programming Interface (API) or plug-ins. The infrastructure and technologies chosen here will utilize the robustness and performance for applications, as well as support quick prototyping for physicists. This paper describes FRIB’s high-level application software architecture and some of the current prototypes.

THPPR047	Design of Superconducting Rotating-gantry for Heavy-ion Therapy	superconducting-magnet, simulation, ion, heavy-ion	4080
	Y. Iwata, T. Furukawa, A. I. Itano, K. Mizushima, S. Mori, K. Noda, T. Shirai NIRS, Chiba-shi, Japan N. Amemiya Kyoto University, Kyoto, Japan T. Fujimoto AEC, Chiba, Japan T.F. Fujita National Institute of Radiological Sciences, Chiba, Japan T. Obana NIFS, Gifu, Japan T. Ogitsu KEK, Ibaraki, Japan T. Orikasa, S.T. Takami, S. Takayama, I. Watanabe Toshiba, Yokohama, Japan
	We designed a superconducting rotating-gantry for heavy-ion therapy. This isocentric rotating-gantry can transport heavy ions having 430 MeV/u to the isocenter with irradiation angles between 0-360 degrees, and further has the capability of our fast raster-scanning irradiation, as employed in the existing fixed-irradiation-ports. For the magnets, combined-function superconducting-magnets will be employed. The use of these superconducting magnets allowed us to design the compact gantry, while keeping a sufficient scan size at the isocenter; the length and radius of the gantry would be approximately 13m and 5.5m, respectively, which are comparable to those of the existing proton gantries. Superconducting coils were designed by using the 3D field solver, so as to obtain uniform field distributions. The two superconducting magnets are being constructed. We will present the design of the superconducting gantry as well as details of the superconducting magnets.

THPPR052	The MedAustron Proton Gantry	dipole, quadrupole, proton, synchrotron	4091
	A. Koschik PSI, Villigen, Switzerland U. Dorda, A. Koschik EBG MedAustron, Wr. Neustadt, Austria D. Meer, E.S. Pedroni Paul Scherrer Institut, Villigen, Switzerland
	The MedAustron project realizes a synchrotron based accelerator facility in Austria for cancer treatment with protons and carbon ions, currently in the construction phase. In order to allow full patient treatment flexibility, one of the four treatment rooms will be equipped with a proton gantry. While its hardware design is a copy of the PSI Gantry 2, different constraints on the beam optics must be accounted for as MedAustron uses a synchrotron as particle accelerator and a rotator to match the beam into the rotated frame, as compared to the cyclotron of the PSI PROSCAN facility. This paper presents the current status of the hardware design and procurement and a review of the design characteristics of the PSI Gantry 2 for the MedAustron case. In particular the stability of the beam parameters during beam scanning over the treatment scan area is investigated in detail. To achieve utmost parallel active scanning performance, the magnet design parameters (edge angles, corrector quadrupole, tapered dipole) have been optimized for PSI Gantry 2. Equivalent studies are undertaken for the MedAustron requirements and constraints in this paper.

Paper

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MOYCP01

Design and Simulation of IOTA - a Novel Concept of Integrable Optics Test Accelerator

electron, focusing, betatron, simulation

16

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

The use of nonlinear lattices with large betatron tune spreads can increase instability and space charge thresholds due to improved Landau damping. Unfortunately, the majority of nonlinear accelerator lattices turn out to be nonintegrable, producing chaotic motion and a complex network of stable and unstable resonances. Recent advances in finding the integrable nonlinear accelerator lattices have led to a proposal to construct at Fermilab a test accelerator with strong nonlinear focusing which avoids resonances and chaotic particle motion. This presentation will outline the main challenges, theoretical design solutions and construction status of the Integrable Optics Test Accelerator underway at Fermilab.

Slides MOYCP01 [2.816 MB]

MOPPC002

Local Chromatic Correction Scheme and Crab-waist Collisions for an Ultra-low β^* at the LHC

sextupole, quadrupole, luminosity, resonance

118

J.L. Abelleira, S. Russenschuck, R. Tomás, F. Zimmermann
CERN, Geneva, Switzerland
J.L. Abelleira
EPFL, Lausanne, Switzerland
C. Milardi, M. Zobov
INFN/LNF, Frascati (Roma), Italy
K. Ohmi
KEK, Ibaraki, Japan
D.N. Shatilov
BINP SB RAS, Novosibirsk, Russia

Funding: Work supported by the European Commission under the FP7 Research Infrastructures project Eu- CARD, grant agreement no. 227579.
We discuss potential merits and the parameter range of interest for a possible crab-waist collision scheme at the LHC, and report preliminary optics studies of a local chromatic correction scheme with flat beams (β_x^*>>β_y^*), which could boost the LHC luminosity by about an order of magnitude and would also allow for crab-waist collisions.

MOPPC003

Very Fast LHC Crab Cavity Failures and their Mitigation

luminosity, simulation, betatron, cavity

121

T. Baer, R. Calaga, R. De Maria, S.D. Fartoukh, E. Jensen, R. Tomás, J. Tückmantel, J. Wenninger, B. Yee-Rendon, F. Zimmermann
CERN, Geneva, Switzerland
T. Baer
University of Hamburg, Hamburg, Germany

For the high-luminosity LHC upgrade program (HL-LHC), the installation of crab cavities (CCs) is needed to compensate the geometric luminosity loss due to the crossing angle and for luminosity leveling [*]. The baseline is a local scheme with CCs around the ATLAS and CMS experiments. In a failure case (e.g. a control failure or arcing in the coupler), the voltage and/or phase of a CC can change significantly with a very fast time constant of the order of 1 to 10 LHC turns. This can lead to large, global betatron oscillations of the beam. The impact of CC failures on the beam dynamics is discussed and the results from dedicated simulations are presented. Mitigation strategies to limit the impact of CC failures to an acceptable level are proposed.
* F. Zimmermann and O. Brüning, “Parameter Space for the LHC High-Luminosity Upgrade”, IPAC'12, MOPPC005, May 2012.

MOPPC005

Parameter Space for the LHC Luminosity Upgrade*

luminosity, target, emittance, brightness

127

F. Zimmermann, O.S. Brüning
CERN, Geneva, Switzerland

Funding: Work supported by the European Commission under the FP7 Research Infrastructures projects EuCARD, grant agreement no. 227579, and HiLumi LHC, grant agreement no. 284404.
We review the parameter space for the high-luminosity upgrade of the LHC (HL-LHC). Starting from the luminosity targets and the primary limitations, e.g., long-range beam-beam effects, event pile up, electron cloud, turnaround time, intrabeam scattering, we determine the range for compatible beam parameters such as the beam intensity, bunch spacing, transverse and longitudinal emittances, bunch length, and IP beta functions required to meet the HL-LHC goals. A selection of a few possible parameter sets is presented for comparison and discussion.

MOPPC006

90m Optics Studies and Operation in the LHC

proton, injection, quadrupole, target

130

H. Burkhardt, G.J. Müller, S. Redaelli, R. Tomás, G. Vanbavinckhove, J. Wenninger
CERN, Geneva, Switzerland
S. Cavalier
LAL, Orsay, France

A high β^* = 90 m optics was commissioned and used for first very forward physics operation in the LHC in 2011. The experience gained from working with this optics in 5 studies and operation periods in 2011 was very positive. The target β^* = 90 m was reached by a de-squeeze from the standard 11 m injection and ramp optics on the first attempt and collisions and first physics results obtained in the second study. The optics was measured and corrected with good precision. The running conditions were very clean and allowed for measurements with roman pots very close to the beam.

MOPPC007

Plans for High Beta Optics in the LHC

quadrupole, emittance, insertion, scattering

133

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

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

MOPPC008

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

proton, scattering, lattice, 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%.

MOPPC010

Parametric Study of Optics Options for the HL-LHC Project

quadrupole, luminosity, insertion, sextupole

142

R. De Maria
CERN, Geneva, Switzerland

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

MOPPC011

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

quadrupole, dynamic-aperture, insertion, injection

145

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

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

MOPPC013

Optics and Lattice Optimizations for the LHC Upgrade Project

luminosity, lattice, 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.

MOPPC016

Combined Ramp and Squeeze at the Large Hadron Collider

injection, quadrupole, collider, dipole

157

S. Redaelli, M. Lamont, G.J. Müller, R. Tomás, J. Wenninger
CERN, Geneva, Switzerland
N. Ryckx
EPFL, Lausanne, Switzerland

In the first two years of operation of the CERN Large Hadron Collider (LHC), the betatron squeeze has been carried out at constant flat top energy of 3.5 TeV. Squeeze setting functions are separated from the energy ramp functions. This ensured a maximum flexibility during commissioning because stopping at all intermediate optics for detailed measurements was possible. In order to then improve the efficiency of the operational cycle, combining the ramp and squeeze has been considered. In this paper, the various possibilities for this scheme are reviewed, and proposals of optimized operational cycles with combined ramp and squeeze are presented for different energies. Results of beam tests are also discussed.

MOPPC023

Polarization Transmission at RHIC, Numerical Simulations

polarization, resonance, simulation, proton

178

F. Méot, M. Bai, C. Liu, M.G. Minty, V.H. Ranjbar
BNL, Upton, Long Island, New York, USA

Ray-tracing methods, using the computer code Zgoubi, have proven efficient for beam and spin dynamics simulations in RHIC (see earlier PAC and IPAC publications). More simulations and results are being produced, including spin code benchmarking and cross-checking, effects of strongest resonances and working point on transport of polarization, polarization with Run 9 and Run 11 measured ramp orbit and optics, polarization profiles, etc. The numerical methods involved are recalled, a status of the work is given.

MOPPC024

Modelling of the AGS Using Zgoubi - Status

simulation, closed-orbit, multipole, coupling

181

F. Méot, L. A. Ahrens, Y. Dutheil, J.W. Glenn, H. Huang, T. Roser, V. Schoefer, N. Tsoupas
BNL, Upton, Long Island, New York, USA

A computer model, based on the ray-tracing code Zgoubi, is being developed in view of on-line simulation of the RHIC injector AGS, and of beam and spin dynamics simulations and studies in the presence of the cold and warm helical partial snakes. A status of this work is given here.

MOPPC030

Status of the Decay Ring Design for the IDS Neutrino Factory

injection, kicker, lattice, insertion

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)

MOPPC045

Scaled Electron Model of a Dogbone Muon RLA with Multi-pass Arcs

linac, electron, quadrupole, dipole

235

S.A. Bogacz, A. Hutton, G.A. Krafft, V.S. Morozov, Y. Roblin
JLAB, Newport News, Virginia, USA
K.B. Beard, R.P. Johnson
Muons, Inc, Batavia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Supported in part by USDOE STTR Grant DE-FG02-08ER86351.
The design of a dogbone RLA with linear-field multi-pass arcs was earlier developed for accelerating muons for a future Neutrino Factory and Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over single pass or pulsed arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme in which a 4.35 MeV/c electron beam is injected in the middle of a 2.9 MeV/pass linac with two double-pass return arcs, and is accelerated to 17.4 MeV/c in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available 1.5 GHz. The footprint of a complete RLA fits in an area of 25 by 7 m. The scheme utilizes only fixed magnetic fields including injection and extraction. The hardware requirements are not very demanding, making it feasible to utilize the existing technologies.
The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

MOPPC074

Evolution of MAD-X in the Framework of LHC Upgrade Studies

multipole, simulation, luminosity, quadrupole

304

A. Latina, L. Deniau
CERN, Geneva, Switzerland

The design efforts for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC) will require significant extensions of the MAD-X code widely used for designing and simulating particles accelerators. For this purpose, several new capabilities have been added to the code, namely the possibility to simulate crab cavities for crossing angle compensation, with their imperfections; the selective introduction of thick quadrupole elements for particles tracking, improving the previous implementation entirely based on thin-lenses; and the upgrade of the interface to SixTrack used for distributed tracking with, e.g., LHC@home. These changes are framed into a global redesign of the MAD-X architecture meant to consolidate its structure, improve its performances, and increase its flexibility. Such improvements are described in details in the present paper.

MOPPC083

LinguaFranca - A Graphical User Interface for Accelerator Modeling

simulation, quadrupole, lattice, 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.

MOPPD057

CERN PSB-to-PS Transfer Modifications for the 2 GeV Upgrade

injection, quadrupole, dipole, septum

493

W. Bartmann, J. Borburgh, S.S. Gilardoni, B. Goddard, A. Newborough, S. Pittet, R. Steerenberg
CERN, Geneva, Switzerland
C.H. Yu
IHEP, Beijing, People's Republic of China

Within the frame of the CERN PS Booster (PSB) energy upgrade from 1.4 to 2 GeV, the PSB to PS transfer line will be adapted for pulse-to-pulse modulated operation. A modified lattice is presented including a re-design of the switching dipole between ISOLDE and PS and additional collimators to protect the PS injection septum. Optics solutions optimized for small emittance LHC beams as well as for the large emittance high-intensity beams are shown.

MOPPD062

Aperture Measurements in the LHC Interaction Regions

injection, emittance, luminosity, resonance

508

S. Redaelli, M.C. Alabau Pons, R.W. Assmann, R. Bruce, M. Giovannozzi, G.J. Müller, M. Pojer, J. Wenninger
CERN, Geneva, Switzerland

The aperture of the LHC interaction regions is crucial for the LHC performance because it determines the smaller β^* that can be achieved. The aperture has been measured at a maximum energy of 3.5 TeV and at different β^* values, following optimized procedure to allow safe measurements at high energy. In this paper, the results of these aperture measurements, which are used as a reference for β^* reach and crossing scheme estimates at the LHC interaction points, are presented.

MOPPD071

Error Localization in RHIC by Fitting Difference Orbit

storage-ring, feedback, closed-orbit, dipole

526

C. Liu, M.G. Minty, V. Ptitsyn
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.
Many errors in an accelerator are evidenced as transverse kicks to the beam, which distort the beam trajectory. Therefore, the information of the errors are imprinted in the distorted orbits, which are different from what would be predicted by the optics model. In this paper, we introduce an algorithm for fitting the orbit based on an on-line optics model. We apply the algorithm to localize the location of the elusive source of vertical diurnal variations observed in RHIC, and analyze D0/Dx errors in local coupling measurement.

MOPPD072

A High Energy Collimation System for the European Spallation Source

collimation, target, beam-losses, linac

529

H.D. Thomsen, A.I.S. Holm, S.P. Møller
ISA, Aarhus, Denmark

At the European Spallation Source (ESS), a ~160 m high energy beam transport (HEBT) system is to guide the high-power (5 MW) proton beam from a superconducting 2.5 GeV linac to a spallation target station. The HEBT could include a single-pass collimation system to protect all downstream accelerator components, including the vital target. The system would be built to withstand both continuous low-power losses (i.e. introduce halo reduction) and infrequent short-term, high-power beam exposure, essentially a fault scenario. Although a collimation system could reduce the uncontrolled beam losses and thus activation levels elsewhere, it takes up precious longitudinal space intended for future beam power upgrades and sets demands for the beam optics, as will be discussed. Possible materials and specifications will also be described.

MOPPD078

Accelerator Physics Study on the Effects from an Asynchronous Beam Dump in the LHC Experimental Region Collimators

proton, simulation, kicker, betatron

547

L. Lari, R.W. Assmann, V. Boccone, R. Bruce, F. Cerutti, A. Mereghetti, A. Rossi, V. Vlachoudis
CERN, Geneva, Switzerland
A. Faus-Golfe, L. Lari
IFIC, Valencia, Spain

Funding: This work has been carried out through of the European Coordination for Accelerator Research and Development (EuCARD), co-sponsored by EU 7th Framework Program.
Asynchronous beam aborts at the LHC are to be expected once per year. Accelerator physics studies of asynchronous dumps have been performed at different beam energies and beta-stars. The loss patterns are analyzed in order to identify the losses in particular on the Phase 1 Tertiary Collimators (TCT), since their Tungsten jaw insert has a low damage threshold with respect to the loss load expected. Settings for the tilt angle of the TCTs are discussed with the aim of reducing the thermal loads on the TCT themselves.

MOPPP016

Feasibility Study of an ERL-based GeV-scale Multi-turn Light Source

linac, brilliance, undulator, cryomodule

604

Y. Petenev, T. Atkinson, A.V. Bondarenko, A.N. Matveenko
HZB, Berlin, Germany

A new generation of particle accelerators based on an Energy Recovery Linac (ERL) is a promising tool for a number of new applications. These include high brilliance light sources in a wide range of photon energies, electron cooling of ion beam and ERL-based electron-hadron colliders. Helmholtz-Zentrum Berlin started a feasibility study of GeV-scale multi-turn ERL-based light source (LS). This LS will work in diffraction limited regime in X-rays and with a short length of a light pulse in femtosecond region. The average and peak brightness will be at least an order of magnitude higher than synchrotron-based LS. In this work an overview of the future multi-turn light source is given. Modeling of the Beam Break Up instability is presented.

MOPPR090

Progress Report on Development of a High Resolution Transverse Diagnostic based on Fiber Optics

electron, diagnostics, radiation, photon

996

R. Tikhoplav, R.B. Agustsson, G. Andonian, A.Y. Murokh, S. Wu
RadiaBeam, Santa Monica, USA
R.K. Li, P. Musumeci, C.M. Scoby
UCLA, Los Angeles, California, USA

A beam profile monitor utilizing the technological advances in fiber optic manufacturing to obtain micron level resolution is under development at RadiaBeam Technologies. This fiber-optic profiling device would provide a low cost, turn-key solution with nominal operational supervision and requires minimal beamline real estate. Preliminary results of Cherenkov light generation in fiber is presented.

TUYA03

Performance and Prospects of BEPCII

luminosity, coupling, feedback, injection

1030

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

BEPCII, the upgrade project of Beijing Electron Positron Collider (BEPC), has been put into operation for both high energy physics experiments as well as synchrotron radiation application since its completion in 2009. The peak luminosity reaches 6.5*10³² cm^-2 s^-1 at 1.89 GeV with e⁺e⁻ collisions of each beam current 700 mA. The collider operates for dedicated synchrotron radiation mode with 250 mA electron beams at 2.5 GeV. The performance of BEPCII should be reported and the measures to upgrade its luminosity described.

Slides TUYA03 [5.529 MB]

TUPPC001

Quadrupole Shapes

quadrupole, TRIUMF, controls, multipole

1149

R.A. Baartman
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

Traditionally, quadrupoles are shaped to have a constant vertical cross-section. In other words, the poles are cylindrical segments extended in the beam direction and circular or hyperbolic in cross section. At the ends, the poles are simply truncated or sometimes slightly smoothed with a chamfer. Even very short quadrupoles are often this shape. A new shape is derived analytically, and it is demonstrated that this shape yields dramatically smaller aberrations.

TUPPC004

Study of a Lattice with a Lower Emittance at SOLEIL

emittance, dipole, lattice, 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.

TUPPC013

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

emittance, photon, lattice, 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

lattice, sextupole, emittance, resonance

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.

TUPPC017

Orbit and Optics Correction to Realize Designed Machine Performance

emittance, lattice, 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.

TUPPC018

Estimation of Orbit and Optics Distortion of SuperKEKB by Tunnel Deformation

emittance, quadrupole, coupling, luminosity

1197

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

The tunnel which was used for the KEKB B-factory is reused for the accelerator tunnel of the SuperKEKB. The total vertical displacement of the tunnel subsidence reached almost 30mm during 10 years KEKB operation. In order to operate the SuperKEKB which might be more delicate machine than the previous KEKB B-factory, we are evaluating the optics distortion by the tunnel deformation and studying the machine performance after the orbit and optics correction. We report the estimation of the machine performance degradation by the tunnel subsidence and the requirement of the correction.

TUPPC020

A Scheme for Horizontal-vertical Coupling Correction at SuperKEKB

coupling, simulation, lattice, 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

lattice, 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.

TUPPC034

Preparation of SLS for IBS Measurements

emittance, diagnostics, impedance, radiation

1233

N. Milas, M. Böge, A. Streun
PSI, Villigen, Switzerland
M. Aiba, A. Lüdeke, A. Saa Hernandez
Paul Scherrer Institut, Villigen, Switzerland
F. Antoniou, Y. Papaphilippou
CERN, Geneva, Switzerland

It is planned to use the SLS for testing damping ring issues related to linear colliders. One aspect is the study of Intra-Beam Scattering (IBS) effects, which are a limiting factor for ultra-low emittance rings. In this paper we present the setup and characterization of a new mode of operation in which the SLS runs at lower energy (1.57 GeV) with a natural emittance of 2.4 nm rad. This is much smaller than that at the nominal energy (2.41 GeV) and should make IBS effects more easily visible. In order to be able to observe IBS a careful setup is required: Optics measurement and correction as well as measurements of the bunch natural energy spread and the onset of turbulent bunch lengthening. Also, a detailed discussion on the available diagnostics and their limitations are shown and finally some preliminary results of beam emittance measurements, in all three planes, as a function of single bunch current are presented.

TUPPC036

Integration with the LHC of Electron Interaction Region Optics for a Ring-ring LHeC

quadrupole, proton, dipole, electron

1239

L.N.S. Thompson
Cockcroft Institute, Warrington, Cheshire, United Kingdom
R. Appleby
UMAN, Manchester, United Kingdom
N.R. Bernard
ETH, Zurich, Switzerland
H. Burkhardt, B.J. Holzer
CERN, Geneva, Switzerland
M. Fitterer
KIT, Karlsruhe, Germany
M. Klein
The University of Liverpool, Liverpool, United Kingdom
P. Kostka
DESY Zeuthen, Zeuthen, Germany

The Large Hadron Electron Collider (LHeC) project is a proposal to study e-p and e-A interactions at the LHC. One design uses an electron synchrotron to collide a 60GeV e± beam with the 7TeV proton beam. Designing a new accelerator around the existing LHC machine poses unique challenges, particularly in the interaction region (IR). The electron beam must be quickly separated from the proton beam after the interaction point (IP) to avoid beam-beam effects, while not significantly reducing luminosity or producing large amounts of synchrotron radiation. The proton beam must pass through the electron optics, while the electron beam must avoid the proton optics. The long straight section requires bending in both planes to counteract the IP crossing angle and to displace the beam vertically from the electron machine to the proton IP. An achromatic bending scheme is used in the vertical plane to eliminate dispersion at the IP and provide an optics which is well matched to the LHeC ring lattice. The interaction region and long straight section design is presented and detailed, and the design process and principles discussed.

TUPPC037

Update on LHeC Ring-Ring Optics

sextupole, insertion, lattice, resonance

1242

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

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

TUPPC038

Interaction Region Optics for the Non-Interacting LHC Proton Beam at the LHeC

proton, electron, quadrupole, synchrotron

1245

L.N.S. Thompson
Cockcroft Institute, Warrington, Cheshire, United Kingdom
R. Appleby
UMAN, Manchester, United Kingdom
O.S. Brüning, B.J. Holzer
CERN, Geneva, Switzerland
M. Klein
The University of Liverpool, Liverpool, United Kingdom
P. Kostka
DESY Zeuthen, Zeuthen, Germany

The Large Hadron Electron Collider project is a proposal to study e-p and e-A interactions at the LHC. Two electron accelerator designs are being studied; a linac and a synchrotron. In the synchrotron option, a 60GeV electron beam is collided with one of the LHC proton beams to provide high luminosity TeV-scale interactions. The interaction region for this scheme is complex and introduces a series of challenges due to the integration of the two machines. One of these is the optics of the second non-interacting proton beam. The second proton beam must not interfere with the LHeC experiment, but simultaneous running of the remaining LHC experiments requires that this beam must still circulate relatively undisturbed. This paper discusses methods to solve these challenges for the electron synchrotron design.

TUPPC040

Model Calibration and Optics Correction Using Orbit Response Matrix in the Fermilab Booster

booster, dipole, acceleration, coupling

1251

M.J. McAteer, S.E. Kopp
The University of Texas at Austin, Austin, Texas, USA
V.A. Lebedev, E. Prebys
Fermilab, Batavia, USA
A.V. Petrenko
BINP SB RAS, Novosibirsk, Russia

A beam-based method of optical model calibration using the measured orbit response matrix, known as the LOCO method, was successfully applied to Fermilab's rapid-cycling Booster synchrotron. Orbit responses were measured by individually changing the strength of each dipole corrector throughout the acceleration cycle, and dispersion was measured by changing the beam's radial offset. The model calibration procedure revealed large calibration errors for all elements in the Booster's recently-installed multipole corrector packages and beam position monitors. The resulting model was used to correct coupling and beta beating.

TUPPC043

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

lattice, proton, linac, 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.

TUPPC044

Emittance and Phase Space Tomography for the Fermilab Linac

emittance, linac, focusing, quadrupole

1263

C. Johnstone, F.G.G. Garcia, T. Kobilarcik, G.M. Koizumi, C.D. Moore, D.L. Newhart
Fermilab, Batavia, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Dept. of Energy.
The Fermilab Linac delivers a variable intensity, 400-MeV beam to the The MuCool Test Area experimental hall via a beam line specifically designed to facilitate measurements of the Linac beam emittance and properties. A 10 m, dispersion-free and magnet-free straight utilizes an upstream quadrupole focusing triplet in combination with the necessary in-straight beam diagnostics to fully characterize the transverse beam properties. Since the Linac does not produce a strictly elliptical phase space, tomography must be performed on the profile data to retrieve the actual particle distribution in phase space. This is achieved by rotating the phase space distribution using different waist focusing conditions of the upstream triplet and performing a de-convolution of the profile data. Preliminary measurements using this diagnostic section are reported here.

TUPPC046

Further Analysis of Real Beam Line Optics from a Synthetic Beam

coupling, linac, closed-orbit, electron

1269

R.M. Bodenstein
UVa, Charlottesville, Virginia, USA
Y. Roblin, M.G. Tiefenback
JLAB, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a license to publish or reproduce this manuscript for U.S. Government purposes.
Standard closed-orbit techniques for Twiss parameter measurement are not applicable to the open-ended Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. The evolution of selected sets of real orbits in the accelerator models the behavior of a “synthetic” beam. This process will be validated against beam profile-based Twiss parameter measurements and should provide the distributed optical information needed to optimize beamline tuning for an open-ended system. This work will discuss the current and future states of this technique, as well as an example of its use in the CEBAF machine.

TUPPC053

Longitudinal Tuning of the SNS Superconducting Linac

cavity, linac, acceleration, controls

1290

T.V. Gorlov
ORNL, Oak Ridge, Tennessee, USA

Funding: This work was supported by SNS through UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 for the U.S. Department of Energy.
The SNS superconducting linac delivers proton beam with about 1 GeV of energy driven by self-consistent RF cavities. Here, we present an experience of the longitudinal tune-up of the SNS superconducting linac where a new application for quick RF phase setup and cavity fault adaptation was created. The routine of superconducting linac tune-up, longitudinal beam manipulation, and radio frequency cavity phase scaling for beam state recovery is presented. The application has direct value for beam optics study and will serve as the basis for longitudinal beam-size manipulation for a laser stripping project.

TUPPC056

Optics Measurements and Corrections at RHIC

quadrupole, proton, luminosity, lattice

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.

TUPPC060

Beam Optics and the pp2pp Setup of the STAR Experiment at RHIC

quadrupole, proton, simulation, scattering

1311

P.H. Pile, W. Guryn, J.H. Lee, S. Tepikian, K. Yip
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.
The newly installed forward detector system at the STAR experiment at RHIC measures small angle elastic and inelastic scattering of polarized protons on polarized protons. The detector system makes use of a pair of Roman Pot (RP) detectors, instrumented with silicon detectors, and located on either side of the STAR intersection region downstream of the DX and D0 dipoles and quadrupole triplets. The parallel to point optics is designed so that scattering angles are determined from position measurements at the RP's with small error. The RP setup allows measurement of position and angle for a subset of the scattered protons. These measured position/angle correlations at the RP's can be compared with optics model predictions to get a measure of the accuracy of the quadrupole triplet current settings. The current in each quadrupole in the triplets is comprised of sums and differences of up to six power supplies and an overall 1% error in the triplet field strengths results in a 4% error in four-momentum transfer squared. This technique is also useful to check the polarity of the skew elements located in each quadrupole triplet. Results of the analysis will be presented.

TUPPC061

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

luminosity, quadrupole, feedback, insertion

1314

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

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

TUPPC063

The AGS Synchrotron with Four Helical Magnets

injection, resonance, betatron, quadrupole

1320

N. Tsoupas, H. Huang, W.W. MacKay, T. Roser, D. Trbojevic
BNL, Upton, Long Island, New York, USA

Funding: *Work supported by the US Department of Energy.
The idea* of using two partial helical magnets was applied successfully to the AGS synchrotron**, to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. This modification provides many advantages over the present setup of the AGS that uses two partial helical magnets. First, the symmetric placement of the four helical magnets allows for a better control of the AGS optics with reduced values of the beta functions especially near beam injection, second, the vertical spin direction during beam injection and extraction is closer to vertical, and third, it provides a larger “spin tune gap” for the placement of both the vertical and horizontal tunes of the AGS during acceleration, second. Although the same spin gap can be obtained with two partial helices of equal strength, the required strength of the two helices makes it impractical. In this paper we will provide results on the spin tune and on the optics of the AGS with four partial helical magnets, and comparison of these results with the present setup of the AGS that uses two partial helical magnets***.
* T. Roser et al., Proc. EPAC04, p. 1577 (2004).
** H. Huang et al., PRL 99, 154801(2007).
*** N. Tsoupas et. al., these proceedings.

TUPPC071

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

simulation, lattice, quadrupole, 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.

TUPPC079

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

quadrupole, lattice, simulation, 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.

TUPPC090

Beam Physics of Integrable Optics Test Accelerator at Fermilab

simulation, betatron, resonance, lattice

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.

TUPPC096

Optimization of the Dynamic Aperture for SPEAR3 Low-emittance Upgrade

sextupole, emittance, resonance, dynamic-aperture

1380

L. Wang, X. Huang, Y. Nosochkov, J.A. Safranek
SLAC, Menlo Park, California, USA
M. Borland
ANL, Argonne, USA

A low emittance upgrade is planned for SPEAR3. As the first phase, the emittance is reduced from 10nm to 7nm without addition magnets. A further upgrade with even lower emittance will require a damping wiggler. There is a smaller dynamic aperture for the lower emittance optics due to the stronger nonlinearity. A Multi-Objective Genetic Optimization (MOGA) code is used to maximize the dynamic aperture. Both the dynamic aperture and beam lifetime are optimized simultaneously. Various configurations of the sextupole magnets have been studied in order to find the best configuration. The betatron tune also can be optimized to minimize resonance effects. The optimized dynamic aperture increases 15% from the normal case and the life time increases from 15 hours to 17 hours. It is important that the increase of the dynamic aperture is mainly in the beam injection direction. Therefore the injection efficiency will benefit from this improvement.

TUPPD016

Collection Optics with the Horn Type Focusing Element made with Separate Conductors

focusing, positron, secondary-beams, scattering

1443

A.A. Mikhailichenko
CLASSE, Ithaca, New York, USA

We describe the device for focusing of charged particles by the system of separated conductors which follow the parabolic profile. Basically this is a horn-type focuser, but with the individual conductors instead of continuous surface. This device allows substantial reduction of fabrication cost with the same focusing properties as the continuous parabolic surface. We recommend this “bird-cage” type system for focusing pions/muons in the projects under discussion in many Laboratories around the World.

TUPPD031

Novel Techniques for Isotope Harvesting at FRIB

simulation, ion, target, resonance

1470

M.A.C. Cummings
Muons, Inc, Batavia, USA
L.L. Bandura
FRIB, East Lansing, Michigan, USA

Exotic isotopes have applications in medicine, industry, and national security. Historically, the U.S. has relied on foreign sources for these isotopes. FRIB will be a domestic source of these isotopes. While FRIB is mainly focused on producing exotic isotopes for basic nuclear physics experiments, it also offers an opportunity to harvest unused isotopes for other applications. It is critical that isotope harvesting take place in a synergistic manner that does not adversely affect experiments that will be simultaneously taking place at the facility. Beam optics schemes will be calculated to determine the best locations and methods of separation. These calculations will use COSY Monte Carlo and G4beamline in conjunction with other state of the art ion optical codes that simulate isotope dynamics in magnetic fields and in matter. The results of these simulations will be used to determine the best beam-target combinations to produce the isotopes that are most in-demand and calculate purities of these isotopes in multiple locations in the fragment separators. Trapping and extraction schemes will also be described to maximally recover pure isotope samples.

TUPPP001

Beam Based Measurements with Superconducting Wigglers at the Canadian Light Source with Applications to Nonlinear Beam Dynamics

wiggler, injection, dynamic-aperture, multipole

1599

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

The Canadian Light Source (CLS) employs two superconducting wigglers for the production of hard x-rays. These wigglers cause a large decrease in injection efficiency. While such a decrease is not unexpected due to the large distortion to the linear optics, a correction to the linear optics does not restore injection efficiency. This inability to restore injection is not predicted by a kickmap model of the wiggler. We performed beam based measurements to construct a phenomenological, nonlinear model of the wiggler. Particle tracking with this wiggler model shows that the reduction in dynamic aperture is due to the amplitude dependent tune shift crossing a resonance, even with the linear optics corrected. Moving the tunes allows us to avoid this resonance and measurements at these tunes show that injection efficiency is not greatly affected by the wigglers.

TUPPP004

Low-alpha Operation for the SOLEIL Storage Ring

injection, coupling, radiation, photon

1608

M.-A. Tordeux, J. Barros, A. Bence, P. Brunelle, N. Hubert, M. Labat, P. Lebasque, A. Nadji, L.S. Nadolski, J.-P. Pollina
SOLEIL, Gif-sur-Yvette, France
C. Evain
PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France

The low momentum compaction factor (alpha) operation has been recently established on the SOLEIL Storage Ring. Both time resolved X-ray and THz radiation user communities are taking benefit from a hybrid filling pattern with a 4.7 ps RMS bunch length. At a value of 1.7 10^-5 (nominal alpha /25) and a current per bunch of 65 μA, stable THz radiation is produced in the range of 8 - 20 cm^-1 (measurements and comparison with Coherent Synchrotron Radiation (CSR) modeling are reported elsewhere*, **). Several low-alpha optics have been investigated and the optics presented at IPAC’11 has been selected for the operation. This paper presents the comprehensive experimental characterization of this optics. Specificities of the low-alpha operation, driven by the very demanding user experiments, are reviewed: closed orbit stability issues, extremely tight injected current step when refilling which implies a specific Linac tuning, low current diagnostics optimization, short bunch measurements, insertion devices effect on the CSR characteristics and radiation safety aspects justified by beam losses at injection.
* C. Evain, A. Loulergue et al., this conference.
** E. Roussel et al., this conference.

TUPPP007

Modifications to the Machine Optics of BESSY II Necessitated by the EMIL Project

undulator, cryogenics, dipole, storage-ring

1614

P.O. Schmid, J. Bahrdt, T. Birke, R. Follath, P. Kuske, D. Simmering, G. Wüstefeld
HZB, Berlin, Germany

The Helmholtz Zentrum Berlin and the Max Planck Society are going to build a new dedicated X-ray beam line at the synchrotron source light source BESSY II which will be used for analyzing materials for renewable energy generation. The new large scale project has been dubbed EMIL. In this document we present the modifications to the machine optics and to what extent these changes affect the performance of BESSY II.

TUPPP010

Spectral and Temporal Observations of CSR at ANKA

radiation, synchrotron, storage-ring, synchrotron-radiation

1623

V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schuh, M. Schwarz, N.J. Smale, M. Streichert
KIT, Karlsruhe, Germany
M.J. Nasse
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
ANKA is a synchrotron light source situated at the Karlsruhe Institute of Technology. Using dedicated low-α-optics at ANKA we can reduce the bunch length and generate Coherent Synchrotron Radiation (CSR). Studies of the coherent emission in the time domain allow us to gain an insight into the longitudinal bunch dynamics. These as well as the systematic investigations of the THz spectrum range can be used for benchmarking of theoretical predictions. In this paper we report about the recent progress in CSR observation using fast THz detectors and a Martin-Puplett spectrometer at the ANKA storage ring.

TUPPP011

Simulations of Fringe Fields and Multipoles for the ANKA Storage Ring Bending Magnets

multipole, simulation, sextupole, storage-ring

1626

M. Streichert, M.J. Nasse
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
V. Afonso Rodriguez, A. Bernhard, N. Hiller, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schwarz, N.J. Smale
KIT, Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
ANKA is the synchrotron light source of the Karlsruhe Institute of Technology (KIT). With a maximum particle energy of 2.5 GeV, the storage ring lattice consists of 16 bending magnets with a nominal magnetic flux density of 1.5 T. For the beam dynamics simulations the consideration of the fringe fields and multipoles is essential. A reference measurement of the longitudinal magnetic flux density profile of a bending magnet exists for a current of 650 A, corresponding to a particle energy of 2.46 GeV. For lower beam energies where the magnets are no longer close to saturation, however, the exact density profiles may vary significantly. In order to derive fringe fields and multipole components for different beam energies, simulations of the magnetic flux density for different beam energies were conducted using a finite element method (FEM). We present the results of the simulations and demonstrate the improvements of the beam dynamics simulations in AT (Accelerator Toolbox).

TUPPP015

Status and Recent Progress of SPring-8

coupling, emittance, lattice, storage-ring

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

lattice, emittance, photon, dipole

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, injection, storage-ring, lattice

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, lattice, 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.

TUPPP034

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

betatron, lattice, 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.

TUPPP065

Progress Report on the SwissFEL Injector Test Facility

emittance, quadrupole, laser, dipole

1747

T. Schietinger, M. Aiba, S. Bettoni, B. Beutner, M. Csatari, K. Doshekenov, Y.-C. Du, M.W. Guetg, C.P. Hauri, R. Ischebeck, F. Le Pimpec, N. Milas, G.L. Orlandi, M. Pedrozzi, P. Peier, E. Prat, S. Reiche, B. Smit, A. Trisorio, C. Vicario
Paul Scherrer Institut, Villigen, Switzerland

The SwissFEL injector test facility at the Paul Scherrer Institute is the principal test bed and demonstration plant for the SwissFEL project, which aims at realizing a hard-X-ray Free Electron Laser by 2017. The RF photoinjector facility has been in operation since 2010 and has recently reached its design energy of 250 MeV. A newly installed movable magnetic chicane allows longitudinal bunch compression studies. We report on the first experience with the bunch compressor and present the latest results of projected and slice emittance measurements.

Poster TUPPP065 [1.801 MB]

TUPPR029

Performance of Linear Collider Beam-Based Alignment Algorithms at FACET

linac, alignment, simulation, emittance

1879

A. Latina, J. Pfingstner, D. Schulte
CERN, Geneva, Switzerland
E. Adli
University of Oslo, Oslo, Norway

The performance of future linear colliders will depend critically on beam-based alignment (BBA) and feedback systems, which will play a crucial role both in the linear and in the non-linear systems of such machines, e.g., the linac and the final-focus. Due to its characteristics, FACET is an ideal test-bench for BBA algorithms and linear collider beam-dynamics in general. We present the results of extensive computer simulations and their experimental verification.

TUPPR035

A Comparative Study for the CLIC Drive Beam Decelerator Optics

quadrupole, injection, alignment, lattice

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.

TUPPR043

New Baseline Design of the ILC RTML System

positron, electron, linac, damping

1915

N. Solyak, V.V. Kapin, A. Vivoli
Fermilab, Batavia, USA
S. Seletskiy
BNL, Upton, Long Island, New York, USA

The new ILC baseline was proposed in 2009 (Strawman baseline - SB2009) to minimize cost of the machine and accommodate many changes made in the design of the accelerator systems. The biggest changes are made in the central area, where BDS, RTML, DR, electron and positron sources are sharing the tunnels. A new layout of the compact DR and re-location of the electron and positron sources to the main tunnel requires a new lattice design for all beamlines in this area. The lattice design was coordinated between accelerator systems and Convention Facility and Siting (CFS) group to eliminate conflicts between beamlines and satisfy construction requirements. In this paper we present a new design of the RTML electron and positron lattices in the central area and other modifications made in the RTML line to accommodate changes to the beamline layouts.

TUPPR056

Parametric Study of the CLIC Damping Rings Delay Ring for Reaching Isochronicity Conditions

dipole, sextupole, damping, quadrupole

1948

P. Zisopoulos, F. Antoniou, Y. Papaphilippou
CERN, Geneva, Switzerland

A delay ring in the CLIC damping rings complex is necessary for recombining the two trains to one with the nominal bunch separation of 0.5ns. The preservation of the longitudinal bunch distribution demands an optics design, which eliminates momentum compaction factor up to high order, allowing the delay ring to function under isochronous conditions. Taking into account thin lens approximation, a qualitative estimation of parameters of the cell that will be used in the delay ring, is given, so as to obtain isochronicity conditions. Considerations on the possibility of tuning the cell under those requirements are finally presented.

TUPPR068

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

sextupole, injection, insertion, quadrupole

1978

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

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

TUPPR077

Simulation Studies for the LHC Long-Range Beam-Beam Compensators

simulation, resonance, collider, betatron

2002

T.L. Rijoff, R.J. Steinhagen, F. Zimmermann
CERN, Geneva, Switzerland

The LHC performance and the minimum crossing angle are limited by long-range beam-beam collisions. Wire compensators can mitigate part of the long-range effects and may allow for smaller crossing angles, smaller β^*, or higher beam intensity. A prototype long-range wire compensator should be installed in the LHC by 2014/15. We report simulation studies examining and comparing the efficiency of the wire compensation, in terms of tune footprint or dynamic aperture, at various candidate locations, with different wire shapes, and for varying transverse distance from the beam.

TUPPR080

Integration of Detector into Interaction Region at MEIC

ion, dipole, solenoid, electron

2011

V.S. Morozov, R. Ent, P. Nadel-Turonski
JLAB, Newport News, Virginia, USA
C. Hyde
Old Dominion University, Norfolk, Virginia, USA

Funding: Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
The Jefferson Lab's Medium-energy Electron Ion Collider (MEIC) is proposed as a next-generation facility for the study of strong interaction (QCD). Accessing the relevant physics requires a full-acceptance detector with a dedicated small-angle high-resolution detection system capable of covering a wide range of momenta (and charge-to-mass ratios) with respect to the original ion beam. We present a design of such a detection system integrated into the collider's interaction region, in which full acceptance is attained by letting small-angle collision products pass through the nearest elements of the machine final-focusing system for further detection. The proposed design is consistent with the current collider optics and demonstrates an excellent performance in terms of detector acceptance and resolution.
The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

TUPPR089

Design Study of Beam Injection for SuperKEKB Main Ring

injection, septum, synchrotron, emittance

2035

T. Mori, N. Iida, M. Kikuchi, T. Mimashi, Y. Sakamoto, H. Sugimoto, S. Takasaki, M. Tawada
KEK, Ibaraki, Japan

The SuperKEKB project is in progress toward the initial physics run in the year 2015. It assumes the nano-beam scheme, in which the emittance of the colliding beams is ε=4.6 nm. The emittance of the injected beam is ε=1.46 nm. To achieve such a low emittance, it is vitally important to preserve the emittance during the transport of the beam from the linac to the main ring. One of the most difficult parts is the injection system. We are considering the synchrotron injection for the electron-line to avoid a beam blowup in the ring after injection, which is caused by a beam-beam interaction with the stored beam. The optics study for electron injection and the current R&D status for the septum magnet will be reported in this paper.

WEEPPB014

The Magnetic Model of the LHC during the 3.5 TeV Run

quadrupole, injection, dipole, controls

2194

E. Todesco, N. Aquilina, M. Giovannozzi, M. Lamont, F. Schmidt, R.J. Steinhagen, M. Strzelczyk, R. Tomás
CERN, Geneva, Switzerland
N.J. Sammut
University of Malta, Information and Communication Technology, Msida, Malta

The magnetic model of the LHC is based on a fit of the magnetic measurements through equations that model the field components (geometric, saturation, persistent) at different currents. In this paper we will review the main results related to the magnetic model during the run of the LHC in 2010-2011: with a top energy of 3.5 TeV, all components of the model but the saturation are visible. We first give an estimate of the reproducibility of the main components and multipolar errors as they can be deduced from beam measurements, i.e. orbit, tune, chromaticity, beta beating and coupling. We then review the main results relative to the decay at injection plateau, dependence on powering history, and snapback at the beginning of the ramp for both tune and chromaticity. We discuss the precision obtained in tracking the magnets during the ramp, where the persistent current components gradually disappear. We conclude by presenting the behaviour of the quadrupoles model during the squeeze. A list of the major changes implemented during the operation together with what are considered as the main open issues is given.

WEPPD049

Characterization of the Engineered Photodiode-based Fiber Link Stabilization Scheme for Optical Synchronization Systems

laser, LLRF, FEL, controls

2627

T. Lamb, M.K. Bock, M. Felber, F. Ludwig, H. Schlarb, S. Schulz
DESY, Hamburg, Germany
S. Jabłoński
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

Pulsed optical synchronization systems are used in modern FELs like FLASH and will be used in the upcoming European XFEL. Their purpose is to distribute synchronization signals with femtosecond stability throughout the machine. Optical fibers are used to transport the pulses carrying the timing information to their end-stations. These fibers have to be continuously delay stabilized in order to achieve the desired precision. In this paper, a photodiode-based detector to measure the drifts of the fiber delay and allows their active correction is presented. Promising results from a first prototype setup of a photodiode-stabilized optical fiber link were the starting point for an engineering of this concept. An enclosure with free-space optics, fiber optics and integrated electronics for the detector, operating at 9.75 GHz, was designed. This unit includes all required parts to stabilize four fiber links. It allows to investigate the temperature sensitivity of the detector. Furthermore, results from drift measurements carried out with a two channel engineered detector are presented in this paper.

WEPPD071

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

simulation, injection, insertion, proton

2687

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

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

WEPPP060

A Robust Transverse Feedback System

feedback, kicker, status, pick-up

2843

M. Alhumaidi, A.M. Zoubir
TU Darmstadt, Darmstadt, Germany

Transverse feedback systems use pickups signals to measure the beam instabilities and kickers to correct the beam. The correction signal is calculated according to the transfer matrices between the pickups and the kickers. However, errors due to magnetic field imperfections and magnets misalignments lead to deviations in the transfer matrices from their nominal values, which affects the feedback quality in a negative manner. In this work we address a new concept for robust feedback system against optics errors or uncertainties. A kicker and multiple pickups are used for each transversal direction. We introduce perturbation terms to the transfer matrices between the kicker and the pickups. Consequently, the Extended Kalman Filter is used to estimate the feedback signal and the perturbation terms by means of the measurements from the pickups. Finally results for the heavy ions synchrotron SIS 18 at the GSI are shown.

WEPPR072

Increasing Instability Thresholds in the SPS by Lowering Transition Energy

emittance, injection, extraction, coupling

3096

H. Bartosik, G. Arduini, T. Argyropoulos, T. Bohl, S. Cettour-Cave, K. Cornelis, J. Esteban Muller, W. Höfle, Y. Papaphilippou, G. Rumolo, B. Salvant, E.N. Shaposhnikova
CERN, Geneva, Switzerland

A new optics for the SPS with lower transition energy was tested experimentally during 2010-2011, showing a significant increase of the single bunch instability thresholds at injection, due to the 3-fold increase of the slip factor. This paper summarizes the series of performed machine studies for different LHC bunch structures and intensities. In particular, the search of the TMCI threshold in the new optics is presented. Observations on the longitudinal multi-bunch stability are compared between the nominal and the low-transition optics. Finally, optics variants with higher vertical tunes are discussed, which can allow to further increase the TMCI and vertical instability thresholds by reducing the vertical beta function.

WEPPR079

Observations of Microbunching Instabilities from a THz Port at Diamond Light Source

radiation, storage-ring, synchrotron, electron

3114

W. Shields, G.E. Boorman, V. Karataev, A. Lyapin
JAI, Egham, Surrey, United Kingdom
R. Bartolini, A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom

Diamond Light source is a third generation synchrotron facility dedicated to producing radiation of outstanding brightness. Above a threshold current, the electron bunches are susceptible to the phenomenon known as the microbunching instability. This instability is characterised by the onset of radiation bursts, the wavelength of which is around one order of magnitude shorter than the bunch length. Near threshold, the bursting occurs quasi-‐periodically, however at higher currents, the bursting appears randomly. The high frequencies involved in these emissions make detection and analysis challenging. A port specifically for the investigation of mm wave emissions has recently been built at Diamond. Ultra fast Schottky Barrier Diode detectors have been installed to obtain data for only a small fraction of the bunch revolution time in an updated data acquisition system. The threshold current and subsequent evolution of the instability have been investigated.

THPPD023

Solenoid Field Calculation of the SuperKEKB Interaction Region

solenoid, quadrupole, interaction-region, superconducting-magnet

3548

N. Ohuchi, Y. Arimoto, M. Iwasaki, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, M. Tawada, K. Tsuchiya, H. Yamaoka
KEK, Ibaraki, Japan

The SuperKEKB is the electron-positron collider, and the target luminosity is 8×10³⁵ cm^-2s⁻¹, which is 40 times larger than the attained luminosity of KEKB. The beam final focus system consists of many types of superconducting magnets as 8 quadrupoles, 40 correctors and 4 compensation solenoids. These focusing magnets and correctors are designed to be operated inside the particle detector, Belle, and under the solenoid field of 1.5 T. From the analysis of beam optics, the solenoid field profile has serious impact on the beam vertical emittance. We designs the solenoid field profile along the Belle axis in a 2-dimensional model as the first step, and now we developed this model to the 3-dimensional calculation in detail. The solenoid field profiles along the both beam lines are generated with the combine solenoid field by the Belle solenoid and the compensation solenoids, and the magnetic components of the magnets and the magnetic shields on the beam lines. The model is very complicate. From the calculation results, we will discuss the influence on the beam optics and the final focusing magnet system.

THPPP030

Near Integer Tune for Polarization Preservation in the AGS

polarization, acceleration, injection, resonance

3797

N. Tsoupas, L. A. Ahrens, M. Bai, K.A. Brown, J.W. Glenn, H. Huang, W.W. MacKay, T. Roser, V. Schoefer, K. Zeno
BNL, Upton, Long Island, New York, USA

Funding: *Work supported by the US Department of Energy.
The high energy (T=250 GeV) polarized proton beam experiments performed in RHIC, require high polarization of the beam. In order to preserve the polarization of the proton beam, during the acceleration in the AGS, which is the pre-injector to RHIC, two partial helical magnets* have been installed in AGS. In order to minimize the loss of the beam polarization due to the various intrinsic spin resonances occurring during the proton acceleration, we constrain the value of the vertical tune to be higher than 8.97. With the AGS running at near integer tune the perturbations caused by the partial helical magnets is large resulting in large beta and dispersion waves. To mitigate the adverse effect of the partial helices on the optics of the AGS, we have introduced compensation quads** in AGS. In this paper we present the beam optics of the AGS which ameliorates this effect of the partial helices.
* H. Huang, et al., Proc. EPAC06, p. 273, (2006).
** N. Tsoupas et al., Proc. PAC07, p. 3723 (2007).

THPPR001

Setting Generation for FAIR

controls, synchrotron, storage-ring, proton

3963

D. Ondreka, J. Fitzek, H. Liebermann, R. Müller
GSI, Darmstadt, Germany

The experimental program envisaged for the Facility for Antiproton and Ion Research (FAIR) requires complex operation schemes of its accelerators and beamlines including parallel operation of several experiments. Thus, there is a strong need to develop an appropriate setting generation system, which shall supply consistent settings for all devices across the facility to support the planned parallel operation modes. This system should also provide standard tools for modifying and accessing the settings. These requirements will be met by using LSA, a generic accelerator modeling framework developed at CERN, as basis for the setting generation system. We will report on the status of the setting generation system for FAIR, covering both the implementation of the physics model as well as the extensions to the LSA framework realized within a collaboration with CERN. Results of the first test runs with the existing GSI synchrotron SIS18 will be presented.

THPPR014

FRIB High-level Software Architecture

controls, EPICS, monitoring, feedback

3996

P. Chu, T.D. Brown, R. Gaul, S. Peng
FRIB, East Lansing, Michigan, USA
E.T. Berryman, V. Vuppala
NSCL, East Lansing, Michigan, USA

Funding: This material is based upon work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The Facility for Rare Isotope Beams (FRIB) is setting up its high-level application software architecture. The architecture is based on Service Oriented Architecture, and consists of back-end data storage, client/service infrastructure, control system connectivity, supporting libraries and front-end Graphical User Interface (GUI). The architecture provides online models of FRIB as a service and allows for storage of both structured and non-structured data. The model for structured data is implemented using the Integrated Relational Model of Installed Systems (IRMIS). The GUI is based on Control System Studio (CSS) framework. Libraries, service, data access and GUI tools will be available as Application Programming Interface (API) or plug-ins. The infrastructure and technologies chosen here will utilize the robustness and performance for applications, as well as support quick prototyping for physicists. This paper describes FRIB’s high-level application software architecture and some of the current prototypes.

THPPR047

Design of Superconducting Rotating-gantry for Heavy-ion Therapy

superconducting-magnet, simulation, ion, heavy-ion

4080

Y. Iwata, T. Furukawa, A. I. Itano, K. Mizushima, S. Mori, K. Noda, T. Shirai
NIRS, Chiba-shi, Japan
N. Amemiya
Kyoto University, Kyoto, Japan
T. Fujimoto
AEC, Chiba, Japan
T.F. Fujita
National Institute of Radiological Sciences, Chiba, Japan
T. Obana
NIFS, Gifu, Japan
T. Ogitsu
KEK, Ibaraki, Japan
T. Orikasa, S.T. Takami, S. Takayama, I. Watanabe
Toshiba, Yokohama, Japan

We designed a superconducting rotating-gantry for heavy-ion therapy. This isocentric rotating-gantry can transport heavy ions having 430 MeV/u to the isocenter with irradiation angles between 0-360 degrees, and further has the capability of our fast raster-scanning irradiation, as employed in the existing fixed-irradiation-ports. For the magnets, combined-function superconducting-magnets will be employed. The use of these superconducting magnets allowed us to design the compact gantry, while keeping a sufficient scan size at the isocenter; the length and radius of the gantry would be approximately 13m and 5.5m, respectively, which are comparable to those of the existing proton gantries. Superconducting coils were designed by using the 3D field solver, so as to obtain uniform field distributions. The two superconducting magnets are being constructed. We will present the design of the superconducting gantry as well as details of the superconducting magnets.

THPPR052

The MedAustron Proton Gantry

dipole, quadrupole, proton, synchrotron

4091

A. Koschik
PSI, Villigen, Switzerland
U. Dorda, A. Koschik
EBG MedAustron, Wr. Neustadt, Austria
D. Meer, E.S. Pedroni
Paul Scherrer Institut, Villigen, Switzerland

The MedAustron project realizes a synchrotron based accelerator facility in Austria for cancer treatment with protons and carbon ions, currently in the construction phase. In order to allow full patient treatment flexibility, one of the four treatment rooms will be equipped with a proton gantry. While its hardware design is a copy of the PSI Gantry 2, different constraints on the beam optics must be accounted for as MedAustron uses a synchrotron as particle accelerator and a rotator to match the beam into the rotated frame, as compared to the cyclotron of the PSI PROSCAN facility. This paper presents the current status of the hardware design and procurement and a review of the design characteristics of the PSI Gantry 2 for the MedAustron case. In particular the stability of the beam parameters during beam scanning over the treatment scan area is investigated in detail. To achieve utmost parallel active scanning performance, the magnet design parameters (edge angles, corrector quadrupole, tapered dipole) have been optimized for PSI Gantry 2. Equivalent studies are undertaken for the MedAustron requirements and constraints in this paper.