IPAC2017 - List of Keywords (focusing)

Paper	Title	Other Keywords	Page
MOPAB041	Quadrupole Scan Measurements in the Beam Transport Line between DESY II and PETRA III	emittance, quadrupole, synchrotron, beam-transport	174
	J. Keil, H. Ehrlichmann, G.K. Sahoo, R. Wanzenberg DESY, Hamburg, Germany
	PETRA III is a 6 GeV third generation synchrotron light source in Hamburg, Germany. The storage ring is operated with a typical beam current of 100 mA and is running in top-up mode. The beam delivered to PETRA III is accelerated by a fast cycling booster synchrotron (DESY II), extracted in a 203 m long beam transport line (E-Weg) and injected afterwards into PETRA III. In the framework of PETRA IV upgrade scenarios the potential for decreasing the extracted emittance from DESY II has been investigated which can be achieved by lowering the extraction energy to 5 GeV and increasing the focusing in DESY II. In addition measuring the emittance of the extracted beam from DESY II and the optics in the beam transport line can help to better understand and improve the injection efficiency of PETRA III. By changing the quadrupole strength and measuring the beam size downstream on a screen monitor in the E-Weg the emittance of DESY II and the Twiss functions at the quadrupole in the E-Weg have been determined. Measurements at different energies and tunes of DESY II will be shown and compared with calculations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB041
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MOPAB049	Development of a Focusing System for the AXSIS Project	linac, solenoid, quadrupole, plasma	203
	T. Vinatier, R.W. Aßmann, U. Dorda, B. Marchetti DESY, Hamburg, Germany
	In this paper, we investigate with ASTRA simulations the achievable performances for several focusing systems considered in the AXSIS project. We focus our attention on the requirements in terms of position of the focal point and bunch transverse size at this point. We show that they cannot be fulfilled with a solenoid resistive electro-magnet, but that it is possible when using a solenoid permanent magnet. The use of a quadrupole doublet proves to be adequate to fulfil the requirement on the position of the focal point and be very close to the one on the bunch transverse size, which could possibly be achieved by a further optimization of the parameters of the doublet. Finally, we also investigate the possibility to use an active plasma lens, showing that it could easily fulfil the requirements but that several points must be carefully studied before considering its implementation.
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MOPAB068	Bunch Shape Monitor Development in J-PARC Linac	vacuum, electron, quadrupole, target	271
	A. Miura, J. Tamura JAEA/J-PARC, Tokai-mura, Japan Y. Liu KEK/JAEA, Ibaraki-Ken, Japan T. Miyao KEK, Ibaraki, Japan
	At Japan accelerator reserch complex (J-PARC), the linac, which serves as the injector for the downstream 3-GeV synchrotron, accelerates a negative-hydrogen-ion beam (H⁻) to obtain a 400-MeV beam energy. We use an accelerating frequency of 324 MHz for the accelerator cavities and of 972 MHz. Both the centroid-phase set point at the frequency jump from 324 MHz to 972 MHz and the phase-width control are key issues for suppressing the excess beam loss. In order to optimize a set point of the tuning cavities, we developed a bunch-shape monitor (BSM) to measure the phase width as well as a tuning strategy to minimize the beam loss. In the development of the BSM, the design developed in the INR, Russia. Because the BSM had first experienced to be used between accelearation cavities, we need to protect the leak-magnetic field from quadrupole magnets and outgas impacts to cavities. We installed a BSM again in the beamline, BSM started to measure the phase width and evaluated its performances with a peak-beam-current dependence. We proposed new strategy to use BSM-measurment data for the tuning cavity. This paper describes the BSM development, its modification, and new strategy.
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MOPAB137	Validation of a Novel Emittance Diagnostic Method for Beams with Significant Space Charge	emittance, space-charge, quadrupole, simulation	451
	R.B. Fiorito, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom M.E. Conde, N.R. Neveu, J.F. Power ANL, Argonne, Illinois, USA O. Mete Apsimon Cockcroft Institute, Lancaster University, Lancaster, United Kingdom A.G. Shkvarunets UMD, College Park, Maryland, USA
	Funding: Work supported by the EU under grant agreement 624890, the STFC Cockcroft Institute Core Grant No. ST/G008248/1. Exact knowledge of beam emittance is of central importance for essentially every accelerator. However, there are only few methods to determine it when the beam has significant space charge. We report on our progress to validate a novel diagnostic method that has been proposed to determine the RMS emittance of an electron beam with space charge. This method uses RMS divergence and beam size data measured at a screen placed in a free drift region for selected values of magnetic focusing strength. A novel algorithm is then used to determine the cross correlation term and consequently the RMS emittance of the beam. Simulations, quadrupole scans, phase space tomography and optical diffraction-dielectric foil radiation interferometry are currently being employed to determine and compare the horizontal (x) and vertical (y) emittances of the 14 MeV witness electron beam at Argonne National Laboratory's Wakefield Accelerator. The results of simulations and current measurements are presented and the advantages of the new technique are discussed.
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MOPIK057	Strategy of Beam Tuning Implementation for the SARAF MEBT and SC Linac	linac, solenoid, quadrupole, simulation	652
	P.A.P. Nghiem, D. Uriot CEA/DSM/IRFU, France B. Dalena, J. Dumas, N. Pichoff CEA/IRFU, Gif-sur-Yvette, France
	Beam dynamics of the MEBT and Superconducting Linac in the SARAF accelerator are being finalized. A strategy for beam tuning implementation is applied to this section, leading to specifying the complete set of error tolerances / beam measurements / correctors. A systematic and precise methodology in several steps is applied, leading to fairly distributing the error budget, from which correction schemes are studied, allowing to determine the necessary beam measurements and correctors.
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MOPIK069	Approximate Matrices for Modeling the Focusing of the Undulator Periods and Undulator End Fields	undulator, betatron, dipole, laser	686
	V. Balandin, N. Golubeva DESY, Hamburg, Germany
	We describe procedure for constructing approximate matrices for modeling the focusing of the undulator periods and undulator end fields and discuss applicability of these matrices to the European XFEL undulators.
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MOPIK122	The Beam Optics of the FFAG Cell of the CBETA ERL Accelerator	quadrupole, electron, optics, dipole	820
	N. Tsoupas, J.S. Berg, S.J. Brooks, G.J. Mahler, F. Méot, V. Ptitsyn, D. Trbojevic BNL, Upton, Long Island, New York, USA J.A. Crittenden Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA S.C. Tygier UMAN, Manchester, United Kingdom
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The CBETA project[] is a prototype electron accelerator for the proposed eRHIC project[]. The electron accelerator is based on the Energy Recovery Linac (ERL) and the Fixed Field Alternating Gradient (FFAG) principles. The FFAG arcs and the straight section of the accelerator are comprised of one focusing and one defocusing quadrupoles which are designed as Halbach-type permanent dipole magnets with quadrupoles component[]. We will present the beam optics of the FFAG cell which is based on 3D field maps derived with the use of the OPERA computer code[*]. We will also present the electromagnetic design of the corrector magnets of the cell. http://arxiv.org/abs/1504.00588 http://arxiv.org/ftp/arxiv/papers/1409/1409.1633.pdf * K. Halbach, Nucl. Instrum. Meth. 169 (1980) pp. 1-10 **** http://www.scientificcomputing.com
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MOPIK124	A New Method to Tune the Nonlinear Lattice Online	lattice, sextupole, betatron, injection	828
	W. Guo, Y. Hidaka, X. Yang BNL, Upton, Long Island, New York, USA
	Most nonlinear lattice tuning methods use only part of the optimization constraints, for example, part of the driving terms, nonlinear detuning, lifetime or injection efficiency. Even though some of the nonlinear properties can be improved, it is not guaranteed the nonlinear lattice is fully optimized. In this paper we propose to optimize the nonlinear lattice by correcting the betatron phase advance and detuning of the off-orbit lattices. It is shown that all the leading order optimization constraints are restored in this approach. One advantage of this new method is that the measurement is independent of BPM calibration errors. We succeed in both simulation and experiment in identifying the intentionally added sextupole errors.
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TUXB1	Non-destructive Beam Profile Monitors	ion, electron, photon, vacuum	1234
	C.P. Welsch The University of Liverpool, Liverpool, United Kingdom C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	This paper will present an overview and comparison between beam induced fluorescence, residual gas ionization and gas jet based beam profile monitors, based on recent experimental and theoretical results at different labs. The achievable image/profile quality and resolution limits will be discussed, along with design consideration for different particle species and primary beam energies. Details may be provided about different classic and novel approaches to gas jet shaping, including nozzle-skimmer and Freznel Zone Plate configurations. Finally, particular challenges such as those arising from monitoring multiple beams in parallel (e.g. proton and electron beam in HLLHC) and solutions for targeting the energy limit within the HLLHC project will be presented.
	Slides TUXB1 [12.557 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUXB1
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TUPAB047	Design of a Low Emittance High Current Photocathode RF Gun for the IPM Linear Accelerator	cavity, gun, emittance, simulation	1431
	M. Dayyani Kelisani, H. Shaker CERN, Geneva, Switzerland H. Shaker IPM, Tehran, Iran
	The IPM accelerator project is developing a 50 MeV linear accelerator as an injector for a terahertz source or an IR FEL. The design specifications require a laser driven photocathode located in one end of a high gradient RF cavity operated at 3 GHz frequency and a solenoid channel for the beam transport. In this work, we report on the RF design of an special photocathode RF gun and its associated focusing channel for the emittance compensation process along the whole injector.
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TUPAB093	Race-Track Microtron with Pulse-to-Pulse Beam Energy Switch	electron, linac, microtron, extraction	1530
	Yu.A. Kubyshin UPC, Barcelona, Spain V.I. Shvedunov, I.Yu. Vladimirov LEA MSU, Moscow, Russia V.I. Shvedunov SINP MSU, Moscow, Russia
	A race-track microtron with a few beam orbits can be an alternative to a standard electron linear accelerator in a number of applications in which high beam power is not needed, like radiation therapy, industrial radiography or cargo inspection. In these cases the advantages of race-track microtrons are low RF power consumption, and consequently low cost of the RF system, and a possibility of beam energy switch in a wide range by extracting the beam from different orbits. In the present work we describe the concept of a race-track microtron with pulse-to-pulse beam energy switch in the range from 3 MeV to 9 MeV. Special attention is given to the optimization of the end magnets of a new type which provide both the accelerating structure bypass and vertical beam focusing.
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TUPVA043	A Code for Optimising Triplet Layout	quadrupole, collider, shielding, proton	2163
	L. van Riesen-Haupt, J.L. Abelleira, E. Cruz Alaniz, A. Seryi JAI, Oxford, United Kingdom
	Funding: EuroCirCol One of the main challenges when designing final focus systems of particle accelerators is maximising the beam stay clear in the strong quadrupole magnets of the inner triplet. Moreover it is desirable to keep the quadrupoles in the inner triplet as short as possible for space and costs reasons but also to reduce chromaticity and simplify corrections schemes. An algorithm that explores the triplet parameter space to optimise both these aspects was written. It uses thin lenses as a first approximation for a broad parameter scan and MADX for more precise calculations. The thin lens algorithm is significantly faster than a full scan using MADX and relatively precise at indicating the approximate area where the optimum solution lies.
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TUPVA089	Preliminary Design of a High-intensity Continuous-wave Deuteron RFQ	rfq, emittance, simulation, linac	2287
	X. Liu RIKEN, Saitama, Japan O. Kamigaito, N. Sakamoto, K. Yamada RIKEN Nishina Center, Wako, Japan
	Funding: This work has been funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan) A high-intensity deuteron linear accelerator is currently beding studied as a promising candidate to treat high-level radioactive wastes through the nuclear transmutation process. This paper presents the study on a design of a 75.5 MHz, 400 mA, continuous-wave deuteron radio-frequency quadrupole (RFQ), which is proposed as the front-end of such a linear accelerator. The results of the beam dynamics simulation suggest that the designed RFQ can accelerate a 400-mA deuteron beam from 100 keV to 2.5 MeV with a transmission rate of 92 ~ 93.3%, depending on the assumed input transverse emittance.
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WEPAB105	Design of the ALS-U Storage Ring Lattice	lattice, emittance, quadrupole, storage-ring	2827
	C. Sun, J.-Y. Jung, H. Nishimura, D. Robin, F. Sannibale, C. Steier, C.A. Swenson, M. Venturini, W. Wan LBNL, Berkeley, California, USA
	Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory is proposing the upgrade of its synchrotron light source to reach soft x-ray diffraction limits within the present ALS footprint. The storage ring lattice design and optimization of this light source is one of the challenging aspects for this proposed upgrade. The candidate upgrade lattice needs not only to fulfill the physics design requirements such as brightness, injection efficiency and beam lifetime, but also to meet engineering constraints such as space limitations, maximum magnet strength as well as beamline port locations. In this paper, we will present the lattice design goals and choices and discuss the optimization approaches for the proposed ALS upgrade.
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WEPIK085	Beam Shaping with 4N-order Multipole Magnets	octupole, multipole, electron, quadrupole	3124
	B.T. Folsom, E. Laface ESS, Lund, Sweden
	A uniformly irradiating beam is beneficial in spallation for preventing irregular wear on the target. For octupoles (n = 4) and higher-order (n = 4N) magnets, passing charged-particle bunches undergo symmetric shaping effects along the x and y axes. Using a Lie-mapping formalism, we illustrate how well Gaussian distributions can be flattened symmetrically in 2D with single, dual-pulse, and RF magnets of 4N order. Incidental shaping effects are also discussed.
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WEPVA017	Efficiency Enhancement Induced by a Precursor Electron Bunch in Quasi-Phase Matched Direct Laser Acceleration	plasma, electron, ion, laser	3289
	C.-Y. Hsieh, S.-H. Chen NCU, Chung Li, Taiwan I. Jovanovic NERS-UM, Ann Arbor, Michigan, USA M.W. Lin National Tsing-Hua University (NTHU), Hsinchu, Taiwan
	Funding: This work is supported by the Ministry of Science and Technology in Taiwan by Grant MOST 104-2112-M-008-013-MY3 and the United States Defense Threat Reduction Agency through contract HDTRA1-11-1-0009 Direct laser acceleration (DLA) of an electron bunch can be achieved by utilizing the axial field of a well-guided, radially polarized laser pulse in a density-modulated plasma waveguide. However, the ponderomotive force of a TW-class laser pulse excites a plasma wave that can generate a defocusing electrostatic field, which significantly deteriorates the transverse properties of the injected electron witness bunch. To improve the quality of the accelerated witness bunch, an additional leading electron bunch, termed as a precursor, is introduced to generate ion-focusing force to effectively confine the trailing witness bunch. We conducted three-dimensional particle-in-cell simulations to investigate the effect of bunch charge, transverse size of the precursor, and the axial separation between the precursor and the witness bunch on the efficacy of DLA. Results indicate that the transverse properties of the witness bunch can be maintained and the overall DLA efficiency can be improved, when a favorable ion-focusing force is provided by the precursor. A. G. York, et al., Phys. Rev. Lett. 100, 195001 (2008). ** M. -W. Lin et al., Phys. Plasmas 21, 093109 (2014).
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THPAB078	Beam Dynamics Studies of the Transverse Gradient Undulator and Its Application to Suppression of Microbunching Instability	FEL, electron, undulator, laser	3895
	T. Liu, Y. Ding, Z. Huang, W. Qin SLAC, Menlo Park, California, USA T. Liu University of Chinese Academy of Sciences, Beijing, People's Republic of China T. Liu, D. Wang SINAP, Shanghai, People's Republic of China
	A transverse gradient undulator (TGU) which was initially proposed for high gain free electron lasers (FELs) driven by electron beams with relatively large energy spread, can be extended to the application of beam dynamics, such as phase-merging enhanced harmonic generation FEL and suppression of microbunching instability. In this contribution we present beam dynamics studies of the TGU, analyze the resulting focusing and dispersion, and discuss the effects of an additional corrector on the TGU. As an application to beam dynamics, we show a feasible transport system based on the TGU as a reversible electron beam heater to suppress the microbunching instability of the electron beam.
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THPIK008	Beam Dynamics for the ThomX Linac	emittance, electron, gun, solenoid	4121
	L. Garolfi, C. Bruni, M. El Khaldi, C. Vallerand LAL, Orsay, France
	We report the results of a recent beam dynamics study that has led to promising working points for the split ThomX photoinjector. ThomX is a back-scattering Thomson light source that will use S-band electron Linac with an energy of 50 MeV to produce 45 keV high X-rays flux (10¹¹ - 10¹³ ph/s), by means of collision between electron bunches and laser pulses, in the energy range from 45 keV to 90 keV. Since Thomx has been conceived to maximise the average X-rays flux in a fixed bandwidth, the high rate electron-photon collisions impose a linear accelerator combined with a storage ring. The high performances of the accelerator are largely affected by the high quality of the electron beam at the interaction point in the ring. Beam specifications should be achieved at the interaction point to the extent that 1 nC, 50 nA average current per bunch with normalised rms transverse emittance less than 5 mm and around 0.3% energy spread, at the end of the linac. The beam dynamics along the linac has been studied to demonstrate the capability of the accelerator to meet the requirements for the high brightness electron beam using an RF photoinjector configuration.
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THPIK098	Bz Calculation of TPS Linac Focusing Coils and a Toolkit for Bz Optimization	toolkit, linac, electron, operation	4321
	H.H. Chen, H.-P. Chang, C.L. Chen, C.-S. Fann, K.-K. Lin, Y.K. Lin, K.L. Tsai NSRRC, Hsinchu, Taiwan
	A set of focusing coils is installed along TPS linac beam centerline at low energy region (< 10 MeV) in order to confine the beam radius within 5 mm. The longitudinal magnetic field calculation along the beam centerline has been carried out in this study. The estimated Bz is obtained based on Biot-Savart law calculation. Then, it is verified by field measurement using Gauss meter at specific centerline locations. Calibration process is performed by comparing the calculated and measured Bz fields at selected operation settings. The comparison result is presented in this report. The linac operation experience indicates that tuning of the coil settings is critical concerning beam property optimization. Consequently, a Bz calculation toolkit is developed to cope with the multi-knobs optimization process while tuning of numerous focusing coils installed in the system at various locations. The applications of the Bz calculation toolkit is briefly described.
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THPVA007	Matching Space-charge Dominated Electron Bunches into the Plasma Accelerator at SINBAD	emittance, electron, plasma, simulation	4429
	J. Zhu, R.W. Aßmann, U. Dorda, B. Marchetti DESY, Hamburg, Germany
	The SINBAD facility (Short and INnovative Bunches and Accelerators at DESY) is foreseen to provide sub-fs to tens of fs electron bunches for Laser Wake-Field Acceleration (LWFA) experiments. In order to avoid emittance growth in plasma cells with ultra-high accelerating gradients the injection and transport of electron bunches with beta functions of mm-size or even smaller are required. This kind of bunch is usually space-charged dominated since the energy is low (< 200 MeV) while the peak current is high for allowing the electron bunches to be used for Free Electron-Laser (FEL) generation. We present the beamline design and explore the possible beam parameters at the SINBAD linac by start-to-end simulations.
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THPVA009	Transverse Beam Dynamics of an 8 MeV Electron Linac	emittance, solenoid, linac, electron	4432
	S. Sanaye Hajari, M. Dayyani Kelisani, H. Shaker IPM, Tehran, Iran S. Haghtalab Shahid Beheshti University, Tehran, Iran
	The IPM Electron Linac is an 8 MeV (upgradable to 11 MeV) electron linear accelerator under development at the Institute for Research in Fundamental Science (IPM), Tehran, Iran. The linac is mainly regarded as a research project providing hands-on experience in the accelerator science and technology. However, it could serve as an x-ray source or play the injector role for a larger facility. The linac consists of a thermionic gun followed by a travelling wave buncher joined to two accelerating tubes. The transverse focusing is provided by the solenoid mag-nets over the buncher and the accelerating structures. Using the code ASTRA, the transverse beam dynamics is studied and optimized in order to limit the RF emittance. Particularly, the effect of coupler asymmetry is investigated, a beam dynamics design of the solenoid channel is presented, and the effect of the solenoid misalignment on the beam quality is examined.
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THPVA027	Commissioning and First Results of the IBEX Paul Trap	ion, electron, gun, experiment	4481
	S.L. Sheehy, E. Carr, L. Martin JAI, Oxford, United Kingdom K. Budzik Warsaw University, Warsaw, Poland D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom C.R. Prior STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The Intense Beam Experiment (IBEX) is a linear Paul trap designed to replicate the dynamics of intense particle beams in accelerators. Similar to the S-POD apparatus at Hiroshima University, IBEX is a small scale experiment which has been constructed and recently commissioned at the Rutherford Appleton Laboratory in the UK. Its aim is to support theoretical studies of next-generation high intensity proton and ion accelerators, complementing existing computer simulation approaches. Here we report on the status of commissioning and first results obtained.
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THPVA071	A Method to Design Multi-Cell Accelerator Cavities	DTL, cavity, linac, drift-tube-linac	4610
	S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	An efficient method for designing multi-cell accelerator cavities has been developed. It is similar to the approach used by Superfish codes for drift-tube linacs (DTL), where a few single cells at representative beam velocities are tuned in 2D and their geometrical parameters are interpolated to cover the required beam-velocity range. The method is implemented using 3D electromagnetic (EM) modeling with CST MicroWave Studio, which allows its application for various types of resonators, e.g., for H-mode cavities. Interpolating results of 3D EM design of tuned representative single-cell cavities leads to a 3D multi-cell cavity model that can be finalized with just a few small adjustments. As a challenging application example, we design multi-cell resonators of three types - cross-bar (CH) and inter-digital (IH) H-mode, as well as DTL - for accelerating muons in the velocity range of v/c = 0.08-0.3, and compare their performance.
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THPVA094	Permanent Halbach Magnet Proton and Superconducting Carbon Cancer Therapy Gantries	proton, ion, permanent-magnet, dipole	4679
	D. Trbojevic, S.J. Brooks, B. Parker, N. Tsoupas BNL, Upton, Long Island, New York, USA W. Lou Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Hadron cancer therapy facilities are expanding exponentially as advantages with respect to other radiation treatments are localized energy deposition at the tumor and reduction of side effects. The main problem of expansion is the high cost and large size of the facility. The largest cost is the delivery systems, especially isocentric gantries. We present first, the permanent Halbach gantry with significant reduction in cost and simplified operation as all treatment energies are transported from an accelerator to the patient through the same Fixed Field Alternating Gradient (FFAG) structure. The superconducting FFAG gantry also transports at one setting all energies required for the cancer treatment of the patient with carbon ions.
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THPVA121	Focusing and Bunching of Ion Beam in Axial Injection Channel of IPHC Cyclotron TR24	bunching, ion, cyclotron, solenoid	4733
	N.Yu. Kazarinov, I.A. Ivanenko JINR, Dubna, Moscow Region, Russia T. Adam, F.R. Osswald, E.K. Traykov IPHC, Strasbourg Cedex 2, France
	The CYRCé cyclotron (CYclotron pour la ReCherche et l'Enseignement) is used at IPHC (Institut Pluridisciplinaire Hubert Curien) for the production of radio-isotopes for diagnostics, medical treatments and fundamental research in radiobiology. The TR24 cyclotron produced and commercialized by ACSI (Canada) delivers a 16-25 MeV proton beam with intensity from few nA up to 500 mcA. The solenoidal focusing instead of existing quadrupole one is proposed in this report. The changing of the focusing elements will give the better beam matching with the acceptance of the spiral inflector of the cyclotron. The parameters of the focusing solenoid is found. Additionally, the main parameters of the bunching system are evaluated in the presence of the beam space charge. This system consists of the buncher installed in the axial injection beam line of the cyclotron. The using of the greedless multi harmonic buncher may increase the accelerated beam current and will give the opportunity to a new proton beam applications.
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MOPAB041

Quadrupole Scan Measurements in the Beam Transport Line between DESY II and PETRA III

emittance, quadrupole, synchrotron, beam-transport

174

J. Keil, H. Ehrlichmann, G.K. Sahoo, R. Wanzenberg
DESY, Hamburg, Germany

PETRA III is a 6 GeV third generation synchrotron light source in Hamburg, Germany. The storage ring is operated with a typical beam current of 100 mA and is running in top-up mode. The beam delivered to PETRA III is accelerated by a fast cycling booster synchrotron (DESY II), extracted in a 203 m long beam transport line (E-Weg) and injected afterwards into PETRA III. In the framework of PETRA IV upgrade scenarios the potential for decreasing the extracted emittance from DESY II has been investigated which can be achieved by lowering the extraction energy to 5 GeV and increasing the focusing in DESY II. In addition measuring the emittance of the extracted beam from DESY II and the optics in the beam transport line can help to better understand and improve the injection efficiency of PETRA III. By changing the quadrupole strength and measuring the beam size downstream on a screen monitor in the E-Weg the emittance of DESY II and the Twiss functions at the quadrupole in the E-Weg have been determined. Measurements at different energies and tunes of DESY II will be shown and compared with calculations.

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MOPAB049

Development of a Focusing System for the AXSIS Project

linac, solenoid, quadrupole, plasma

203

T. Vinatier, R.W. Aßmann, U. Dorda, B. Marchetti
DESY, Hamburg, Germany

In this paper, we investigate with ASTRA simulations the achievable performances for several focusing systems considered in the AXSIS project. We focus our attention on the requirements in terms of position of the focal point and bunch transverse size at this point. We show that they cannot be fulfilled with a solenoid resistive electro-magnet, but that it is possible when using a solenoid permanent magnet. The use of a quadrupole doublet proves to be adequate to fulfil the requirement on the position of the focal point and be very close to the one on the bunch transverse size, which could possibly be achieved by a further optimization of the parameters of the doublet. Finally, we also investigate the possibility to use an active plasma lens, showing that it could easily fulfil the requirements but that several points must be carefully studied before considering its implementation.

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MOPAB068

Bunch Shape Monitor Development in J-PARC Linac

vacuum, electron, quadrupole, target

271

A. Miura, J. Tamura
JAEA/J-PARC, Tokai-mura, Japan
Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
T. Miyao
KEK, Ibaraki, Japan

At Japan accelerator reserch complex (J-PARC), the linac, which serves as the injector for the downstream 3-GeV synchrotron, accelerates a negative-hydrogen-ion beam (H⁻) to obtain a 400-MeV beam energy. We use an accelerating frequency of 324 MHz for the accelerator cavities and of 972 MHz. Both the centroid-phase set point at the frequency jump from 324 MHz to 972 MHz and the phase-width control are key issues for suppressing the excess beam loss. In order to optimize a set point of the tuning cavities, we developed a bunch-shape monitor (BSM) to measure the phase width as well as a tuning strategy to minimize the beam loss. In the development of the BSM, the design developed in the INR, Russia. Because the BSM had first experienced to be used between accelearation cavities, we need to protect the leak-magnetic field from quadrupole magnets and outgas impacts to cavities. We installed a BSM again in the beamline, BSM started to measure the phase width and evaluated its performances with a peak-beam-current dependence. We proposed new strategy to use BSM-measurment data for the tuning cavity. This paper describes the BSM development, its modification, and new strategy.

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MOPAB137

Validation of a Novel Emittance Diagnostic Method for Beams with Significant Space Charge

emittance, space-charge, quadrupole, simulation

451

R.B. Fiorito, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom
M.E. Conde, N.R. Neveu, J.F. Power
ANL, Argonne, Illinois, USA
O. Mete Apsimon
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
A.G. Shkvarunets
UMD, College Park, Maryland, USA

Funding: Work supported by the EU under grant agreement 624890, the STFC Cockcroft Institute Core Grant No. ST/G008248/1.
Exact knowledge of beam emittance is of central importance for essentially every accelerator. However, there are only few methods to determine it when the beam has significant space charge. We report on our progress to validate a novel diagnostic method that has been proposed to determine the RMS emittance of an electron beam with space charge. This method uses RMS divergence and beam size data measured at a screen placed in a free drift region for selected values of magnetic focusing strength. A novel algorithm is then used to determine the cross correlation term and consequently the RMS emittance of the beam. Simulations, quadrupole scans, phase space tomography and optical diffraction-dielectric foil radiation interferometry are currently being employed to determine and compare the horizontal (x) and vertical (y) emittances of the 14 MeV witness electron beam at Argonne National Laboratory's Wakefield Accelerator. The results of simulations and current measurements are presented and the advantages of the new technique are discussed.

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MOPIK057

Strategy of Beam Tuning Implementation for the SARAF MEBT and SC Linac

linac, solenoid, quadrupole, simulation

652

P.A.P. Nghiem, D. Uriot
CEA/DSM/IRFU, France
B. Dalena, J. Dumas, N. Pichoff
CEA/IRFU, Gif-sur-Yvette, France

Beam dynamics of the MEBT and Superconducting Linac in the SARAF accelerator are being finalized. A strategy for beam tuning implementation is applied to this section, leading to specifying the complete set of error tolerances / beam measurements / correctors. A systematic and precise methodology in several steps is applied, leading to fairly distributing the error budget, from which correction schemes are studied, allowing to determine the necessary beam measurements and correctors.

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MOPIK069

Approximate Matrices for Modeling the Focusing of the Undulator Periods and Undulator End Fields

undulator, betatron, dipole, laser

686

V. Balandin, N. Golubeva
DESY, Hamburg, Germany

We describe procedure for constructing approximate matrices for modeling the focusing of the undulator periods and undulator end fields and discuss applicability of these matrices to the European XFEL undulators.

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MOPIK122

The Beam Optics of the FFAG Cell of the CBETA ERL Accelerator

quadrupole, electron, optics, dipole

820

N. Tsoupas, J.S. Berg, S.J. Brooks, G.J. Mahler, F. Méot, V. Ptitsyn, D. Trbojevic
BNL, Upton, Long Island, New York, USA
J.A. Crittenden
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
S.C. Tygier
UMAN, Manchester, United Kingdom

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The CBETA project[*] is a prototype electron accelerator for the proposed eRHIC project[**]. The electron accelerator is based on the Energy Recovery Linac (ERL) and the Fixed Field Alternating Gradient (FFAG) principles. The FFAG arcs and the straight section of the accelerator are comprised of one focusing and one defocusing quadrupoles which are designed as Halbach-type permanent dipole magnets with quadrupoles component[***]. We will present the beam optics of the FFAG cell which is based on 3D field maps derived with the use of the OPERA computer code[****]. We will also present the electromagnetic design of the corrector magnets of the cell.
* http://arxiv.org/abs/1504.00588
** http://arxiv.org/ftp/arxiv/papers/1409/1409.1633.pdf
*** K. Halbach, Nucl. Instrum. Meth. 169 (1980) pp. 1-10
**** http://www.scientificcomputing.com

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MOPIK124

A New Method to Tune the Nonlinear Lattice Online

lattice, sextupole, betatron, injection

828

W. Guo, Y. Hidaka, X. Yang
BNL, Upton, Long Island, New York, USA

Most nonlinear lattice tuning methods use only part of the optimization constraints, for example, part of the driving terms, nonlinear detuning, lifetime or injection efficiency. Even though some of the nonlinear properties can be improved, it is not guaranteed the nonlinear lattice is fully optimized. In this paper we propose to optimize the nonlinear lattice by correcting the betatron phase advance and detuning of the off-orbit lattices. It is shown that all the leading order optimization constraints are restored in this approach. One advantage of this new method is that the measurement is independent of BPM calibration errors. We succeed in both simulation and experiment in identifying the intentionally added sextupole errors.

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TUXB1

Non-destructive Beam Profile Monitors

ion, electron, photon, vacuum

1234

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

This paper will present an overview and comparison between beam induced fluorescence, residual gas ionization and gas jet based beam profile monitors, based on recent experimental and theoretical results at different labs. The achievable image/profile quality and resolution limits will be discussed, along with design consideration for different particle species and primary beam energies. Details may be provided about different classic and novel approaches to gas jet shaping, including nozzle-skimmer and Freznel Zone Plate configurations. Finally, particular challenges such as those arising from monitoring multiple beams in parallel (e.g. proton and electron beam in HLLHC) and solutions for targeting the energy limit within the HLLHC project will be presented.

Slides TUXB1 [12.557 MB]

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TUPAB047

Design of a Low Emittance High Current Photocathode RF Gun for the IPM Linear Accelerator

cavity, gun, emittance, simulation

1431

M. Dayyani Kelisani, H. Shaker
CERN, Geneva, Switzerland
H. Shaker
IPM, Tehran, Iran

The IPM accelerator project is developing a 50 MeV linear accelerator as an injector for a terahertz source or an IR FEL. The design specifications require a laser driven photocathode located in one end of a high gradient RF cavity operated at 3 GHz frequency and a solenoid channel for the beam transport. In this work, we report on the RF design of an special photocathode RF gun and its associated focusing channel for the emittance compensation process along the whole injector.

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TUPAB093

Race-Track Microtron with Pulse-to-Pulse Beam Energy Switch

electron, linac, microtron, extraction

1530

Yu.A. Kubyshin
UPC, Barcelona, Spain
V.I. Shvedunov, I.Yu. Vladimirov
LEA MSU, Moscow, Russia
V.I. Shvedunov
SINP MSU, Moscow, Russia

A race-track microtron with a few beam orbits can be an alternative to a standard electron linear accelerator in a number of applications in which high beam power is not needed, like radiation therapy, industrial radiography or cargo inspection. In these cases the advantages of race-track microtrons are low RF power consumption, and consequently low cost of the RF system, and a possibility of beam energy switch in a wide range by extracting the beam from different orbits. In the present work we describe the concept of a race-track microtron with pulse-to-pulse beam energy switch in the range from 3 MeV to 9 MeV. Special attention is given to the optimization of the end magnets of a new type which provide both the accelerating structure bypass and vertical beam focusing.

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TUPVA043

A Code for Optimising Triplet Layout

quadrupole, collider, shielding, proton

2163

L. van Riesen-Haupt, J.L. Abelleira, E. Cruz Alaniz, A. Seryi
JAI, Oxford, United Kingdom

Funding: EuroCirCol
One of the main challenges when designing final focus systems of particle accelerators is maximising the beam stay clear in the strong quadrupole magnets of the inner triplet. Moreover it is desirable to keep the quadrupoles in the inner triplet as short as possible for space and costs reasons but also to reduce chromaticity and simplify corrections schemes. An algorithm that explores the triplet parameter space to optimise both these aspects was written. It uses thin lenses as a first approximation for a broad parameter scan and MADX for more precise calculations. The thin lens algorithm is significantly faster than a full scan using MADX and relatively precise at indicating the approximate area where the optimum solution lies.

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TUPVA089

Preliminary Design of a High-intensity Continuous-wave Deuteron RFQ

rfq, emittance, simulation, linac

2287

X. Liu
RIKEN, Saitama, Japan
O. Kamigaito, N. Sakamoto, K. Yamada
RIKEN Nishina Center, Wako, Japan

Funding: This work has been funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan)
A high-intensity deuteron linear accelerator is currently beding studied as a promising candidate to treat high-level radioactive wastes through the nuclear transmutation process. This paper presents the study on a design of a 75.5 MHz, 400 mA, continuous-wave deuteron radio-frequency quadrupole (RFQ), which is proposed as the front-end of such a linear accelerator. The results of the beam dynamics simulation suggest that the designed RFQ can accelerate a 400-mA deuteron beam from 100 keV to 2.5 MeV with a transmission rate of 92 ~ 93.3%, depending on the assumed input transverse emittance.

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WEPAB105

Design of the ALS-U Storage Ring Lattice

lattice, emittance, quadrupole, storage-ring

2827

C. Sun, J.-Y. Jung, H. Nishimura, D. Robin, F. Sannibale, C. Steier, C.A. Swenson, M. Venturini, W. Wan
LBNL, Berkeley, California, USA

Funding: The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory is proposing the upgrade of its synchrotron light source to reach soft x-ray diffraction limits within the present ALS footprint. The storage ring lattice design and optimization of this light source is one of the challenging aspects for this proposed upgrade. The candidate upgrade lattice needs not only to fulfill the physics design requirements such as brightness, injection efficiency and beam lifetime, but also to meet engineering constraints such as space limitations, maximum magnet strength as well as beamline port locations. In this paper, we will present the lattice design goals and choices and discuss the optimization approaches for the proposed ALS upgrade.

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WEPIK085

Beam Shaping with 4N-order Multipole Magnets

octupole, multipole, electron, quadrupole

3124

B.T. Folsom, E. Laface
ESS, Lund, Sweden

A uniformly irradiating beam is beneficial in spallation for preventing irregular wear on the target. For octupoles (n = 4) and higher-order (n = 4N) magnets, passing charged-particle bunches undergo symmetric shaping effects along the x and y axes. Using a Lie-mapping formalism, we illustrate how well Gaussian distributions can be flattened symmetrically in 2D with single, dual-pulse, and RF magnets of 4N order. Incidental shaping effects are also discussed.

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WEPVA017

Efficiency Enhancement Induced by a Precursor Electron Bunch in Quasi-Phase Matched Direct Laser Acceleration

plasma, electron, ion, laser

3289

C.-Y. Hsieh, S.-H. Chen
NCU, Chung Li, Taiwan
I. Jovanovic
NERS-UM, Ann Arbor, Michigan, USA
M.W. Lin
National Tsing-Hua University (NTHU), Hsinchu, Taiwan

Funding: This work is supported by the Ministry of Science and Technology in Taiwan by Grant MOST 104-2112-M-008-013-MY3 and the United States Defense Threat Reduction Agency through contract HDTRA1-11-1-0009
Direct laser acceleration (DLA) of an electron bunch can be achieved by utilizing the axial field of a well-guided, radially polarized laser pulse in a density-modulated plasma waveguide*. However, the ponderomotive force of a TW-class laser pulse excites a plasma wave that can generate a defocusing electrostatic field, which significantly deteriorates the transverse properties of the injected electron witness bunch**. To improve the quality of the accelerated witness bunch, an additional leading electron bunch, termed as a precursor, is introduced to generate ion-focusing force to effectively confine the trailing witness bunch. We conducted three-dimensional particle-in-cell simulations to investigate the effect of bunch charge, transverse size of the precursor, and the axial separation between the precursor and the witness bunch on the efficacy of DLA. Results indicate that the transverse properties of the witness bunch can be maintained and the overall DLA efficiency can be improved, when a favorable ion-focusing force is provided by the precursor.
* A. G. York, et al., Phys. Rev. Lett. 100, 195001 (2008).
** M. -W. Lin et al., Phys. Plasmas 21, 093109 (2014).

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THPAB078

Beam Dynamics Studies of the Transverse Gradient Undulator and Its Application to Suppression of Microbunching Instability

FEL, electron, undulator, laser

3895

T. Liu, Y. Ding, Z. Huang, W. Qin
SLAC, Menlo Park, California, USA
T. Liu
University of Chinese Academy of Sciences, Beijing, People's Republic of China
T. Liu, D. Wang
SINAP, Shanghai, People's Republic of China

A transverse gradient undulator (TGU) which was initially proposed for high gain free electron lasers (FELs) driven by electron beams with relatively large energy spread, can be extended to the application of beam dynamics, such as phase-merging enhanced harmonic generation FEL and suppression of microbunching instability. In this contribution we present beam dynamics studies of the TGU, analyze the resulting focusing and dispersion, and discuss the effects of an additional corrector on the TGU. As an application to beam dynamics, we show a feasible transport system based on the TGU as a reversible electron beam heater to suppress the microbunching instability of the electron beam.

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THPIK008

Beam Dynamics for the ThomX Linac

emittance, electron, gun, solenoid

4121

L. Garolfi, C. Bruni, M. El Khaldi, C. Vallerand
LAL, Orsay, France

We report the results of a recent beam dynamics study that has led to promising working points for the split ThomX photoinjector. ThomX is a back-scattering Thomson light source that will use S-band electron Linac with an energy of 50 MeV to produce 45 keV high X-rays flux (10¹¹ - 10¹³ ph/s), by means of collision between electron bunches and laser pulses, in the energy range from 45 keV to 90 keV. Since Thomx has been conceived to maximise the average X-rays flux in a fixed bandwidth, the high rate electron-photon collisions impose a linear accelerator combined with a storage ring. The high performances of the accelerator are largely affected by the high quality of the electron beam at the interaction point in the ring. Beam specifications should be achieved at the interaction point to the extent that 1 nC, 50 nA average current per bunch with normalised rms transverse emittance less than 5 mm and around 0.3% energy spread, at the end of the linac. The beam dynamics along the linac has been studied to demonstrate the capability of the accelerator to meet the requirements for the high brightness electron beam using an RF photoinjector configuration.

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THPIK098

Bz Calculation of TPS Linac Focusing Coils and a Toolkit for Bz Optimization

toolkit, linac, electron, operation

4321

H.H. Chen, H.-P. Chang, C.L. Chen, C.-S. Fann, K.-K. Lin, Y.K. Lin, K.L. Tsai
NSRRC, Hsinchu, Taiwan

A set of focusing coils is installed along TPS linac beam centerline at low energy region (< 10 MeV) in order to confine the beam radius within 5 mm. The longitudinal magnetic field calculation along the beam centerline has been carried out in this study. The estimated Bz is obtained based on Biot-Savart law calculation. Then, it is verified by field measurement using Gauss meter at specific centerline locations. Calibration process is performed by comparing the calculated and measured Bz fields at selected operation settings. The comparison result is presented in this report. The linac operation experience indicates that tuning of the coil settings is critical concerning beam property optimization. Consequently, a Bz calculation toolkit is developed to cope with the multi-knobs optimization process while tuning of numerous focusing coils installed in the system at various locations. The applications of the Bz calculation toolkit is briefly described.

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THPVA007

Matching Space-charge Dominated Electron Bunches into the Plasma Accelerator at SINBAD

emittance, electron, plasma, simulation

4429

J. Zhu, R.W. Aßmann, U. Dorda, B. Marchetti
DESY, Hamburg, Germany

The SINBAD facility (Short and INnovative Bunches and Accelerators at DESY) is foreseen to provide sub-fs to tens of fs electron bunches for Laser Wake-Field Acceleration (LWFA) experiments. In order to avoid emittance growth in plasma cells with ultra-high accelerating gradients the injection and transport of electron bunches with beta functions of mm-size or even smaller are required. This kind of bunch is usually space-charged dominated since the energy is low (< 200 MeV) while the peak current is high for allowing the electron bunches to be used for Free Electron-Laser (FEL) generation. We present the beamline design and explore the possible beam parameters at the SINBAD linac by start-to-end simulations.

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THPVA009

Transverse Beam Dynamics of an 8 MeV Electron Linac

emittance, solenoid, linac, electron

4432

S. Sanaye Hajari, M. Dayyani Kelisani, H. Shaker
IPM, Tehran, Iran
S. Haghtalab
Shahid Beheshti University, Tehran, Iran

The IPM Electron Linac is an 8 MeV (upgradable to 11 MeV) electron linear accelerator under development at the Institute for Research in Fundamental Science (IPM), Tehran, Iran. The linac is mainly regarded as a research project providing hands-on experience in the accelerator science and technology. However, it could serve as an x-ray source or play the injector role for a larger facility. The linac consists of a thermionic gun followed by a travelling wave buncher joined to two accelerating tubes. The transverse focusing is provided by the solenoid mag-nets over the buncher and the accelerating structures. Using the code ASTRA, the transverse beam dynamics is studied and optimized in order to limit the RF emittance. Particularly, the effect of coupler asymmetry is investigated, a beam dynamics design of the solenoid channel is presented, and the effect of the solenoid misalignment on the beam quality is examined.

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THPVA027

Commissioning and First Results of the IBEX Paul Trap

ion, electron, gun, experiment

4481

S.L. Sheehy, E. Carr, L. Martin
JAI, Oxford, United Kingdom
K. Budzik
Warsaw University, Warsaw, Poland
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
C.R. Prior
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The Intense Beam Experiment (IBEX) is a linear Paul trap designed to replicate the dynamics of intense particle beams in accelerators. Similar to the S-POD apparatus at Hiroshima University, IBEX is a small scale experiment which has been constructed and recently commissioned at the Rutherford Appleton Laboratory in the UK. Its aim is to support theoretical studies of next-generation high intensity proton and ion accelerators, complementing existing computer simulation approaches. Here we report on the status of commissioning and first results obtained.

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THPVA071

A Method to Design Multi-Cell Accelerator Cavities

DTL, cavity, linac, drift-tube-linac

4610

S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

An efficient method for designing multi-cell accelerator cavities has been developed. It is similar to the approach used by Superfish codes for drift-tube linacs (DTL), where a few single cells at representative beam velocities are tuned in 2D and their geometrical parameters are interpolated to cover the required beam-velocity range. The method is implemented using 3D electromagnetic (EM) modeling with CST MicroWave Studio, which allows its application for various types of resonators, e.g., for H-mode cavities. Interpolating results of 3D EM design of tuned representative single-cell cavities leads to a 3D multi-cell cavity model that can be finalized with just a few small adjustments. As a challenging application example, we design multi-cell resonators of three types - cross-bar (CH) and inter-digital (IH) H-mode, as well as DTL - for accelerating muons in the velocity range of v/c = 0.08-0.3, and compare their performance.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA071

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THPVA094

Permanent Halbach Magnet Proton and Superconducting Carbon Cancer Therapy Gantries

proton, ion, permanent-magnet, dipole

4679

D. Trbojevic, S.J. Brooks, B. Parker, N. Tsoupas
BNL, Upton, Long Island, New York, USA
W. Lou
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Hadron cancer therapy facilities are expanding exponentially as advantages with respect to other radiation treatments are localized energy deposition at the tumor and reduction of side effects. The main problem of expansion is the high cost and large size of the facility. The largest cost is the delivery systems, especially isocentric gantries. We present first, the permanent Halbach gantry with significant reduction in cost and simplified operation as all treatment energies are transported from an accelerator to the patient through the same Fixed Field Alternating Gradient (FFAG) structure. The superconducting FFAG gantry also transports at one setting all energies required for the cancer treatment of the patient with carbon ions.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA094

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THPVA121

Focusing and Bunching of Ion Beam in Axial Injection Channel of IPHC Cyclotron TR24

bunching, ion, cyclotron, solenoid

4733

N.Yu. Kazarinov, I.A. Ivanenko
JINR, Dubna, Moscow Region, Russia
T. Adam, F.R. Osswald, E.K. Traykov
IPHC, Strasbourg Cedex 2, France

The CYRCé cyclotron (CYclotron pour la ReCherche et l'Enseignement) is used at IPHC (Institut Pluridisciplinaire Hubert Curien) for the production of radio-isotopes for diagnostics, medical treatments and fundamental research in radiobiology. The TR24 cyclotron produced and commercialized by ACSI (Canada) delivers a 16-25 MeV proton beam with intensity from few nA up to 500 mcA. The solenoidal focusing instead of existing quadrupole one is proposed in this report. The changing of the focusing elements will give the better beam matching with the acceptance of the spiral inflector of the cyclotron. The parameters of the focusing solenoid is found. Additionally, the main parameters of the bunching system are evaluated in the presence of the beam space charge. This system consists of the buncher installed in the axial injection beam line of the cyclotron. The using of the greedless multi harmonic buncher may increase the accelerated beam current and will give the opportunity to a new proton beam applications.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPVA121

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