IPAC2011 - List of Keywords (septum)

Paper	Title	Other Keywords	Page
MOPZ004	Studies for the PRISM FFAG Ring for the Next Generation Muon to Electron Conversion Experiment	injection, kicker, electron, extraction	826
	J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom M. Aslaninejad, L.J. Jenner, A. Kurup, J. Pasternak, Y. Shi, Y. Uchida Imperial College of Science and Technology, Department of Physics, London, United Kingdom R.J. Barlow UMAN, Manchester, United Kingdom K.M. Hock, B.D. Muratori Cockcroft Institute, Warrington, Cheshire, United Kingdom D.J. Kelliher, S. Machida, C.R. Prior STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom Y. Kuno, A. Sato Osaka University, Osaka, Japan J.-B. Lagrange, Y. Mori KURRI, Osaka, Japan M. Lancaster UCL, London, United Kingdom C. Ohmori KEK, Tokai, Ibaraki, Japan T. Planche TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada S.L. Smith STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom H. Witte, T. Yokoi JAI, Oxford, United Kingdom
	High intensity and high quality muon beams are needed for the next generation lepton flavour violation experiments. Such beams can be produced by sending a short proton pulse to a pion production target, capturing the pions and performing RF phase rotation on the resulting muon beam in an FFAG ring. Such a solution was proposed for the PRISM project and this paper summarizes its current status. In particular the PRISM task force was created to address the accelerator and detector issues that need to be solved in order to realise the PRISM experiment. Alternative designs for the PRISM FFAG ring are discussed and their performance compared. The injection/extraction systems and matching to the solenoid channels upstream and downstream of the FFAG ring are presented. The future direction for the study will be outlined.

MOPZ029	Aperture Windows in High-Gradient Cavities for Accelerating Low-Energy Muons	cavity, linac, target, vacuum	862
	S.S. Kurennoy, A.J. Jason, W.M. Tuzel LANL, Los Alamos, New Mexico, USA
	A high-gradient linear accelerator for accelerating low-energy muons and pions in a strong solenoidal magnetic field has been proposed for homeland defense and industrial applications. The acceleration starts immediately after collection of pions from a target in a solenoidal magnetic field and brings muons to a kinetic energy of about 200 MeV over a distance of the order of 10 m. At this energy, both ionization cooling of the muon beam and its further acceleration become feasible. A normal-conducting linac with external-solenoid focusing can provide the required large beam acceptances. The linac consists of independently fed zero-mode (TM010) RF cavities with wide beam apertures closed by thin conducting windows. The high gradients lead to significant heat deposition on the aperture windows. Here we explore options for the edge-cooled thin windows in the zero-mode cavities. Electromagnetic and thermal-stress computations are complemented by thermal-test experiments to select the best solution for the aperture windows. S.S. Kurennoy, A.J. Jason, H. Miyadera, “Large-Acceptance Linac for Accelerating Low-Energy Muons,” Proc. of IPAC10, p. 3518 (2010).

MOPZ038	EMMA Injection and Extraction	injection, extraction, dipole, kicker	883
	B.D. Muratori, J.K. Jones STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom Y. Giboudot Brunel University, Middlesex, United Kingdom D.J. Holder The University of Liverpool, Liverpool, United Kingdom
	EMMA (Electron Machine with Many Applications) is a prototype non-scaling electron FFAG hosted at Daresbury Laboratory. NS-FFAGs related to EMMA have an unprecedented potential for medical accelerators for carbon and proton hadron therapy. They could also be used as the accelerator for a sub-critical reactor. We summarize the design and commissioning of both the injection and extraction lines for this machine. In particular, we look at the commissioning challenges of injection and extraction.

TUYB01	First Results from the EMMA Experiment	acceleration, electron, cavity, injection	951
	S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	Report on first commissioning results and operational experience with EMMA, the world's first nonscaling FFAG. In particular review the effect of resonance crossing, and the efficiency of serpentine acceleration.
	Slides TUYB01 [9.201 MB]

TUPC053	Superconducting Positron Stacking Ring for CLIC	positron, injection, damping, synchrotron	1117
	F. Zimmermann, L. Rinolfi CERN, Geneva, Switzerland E.V. Bulyak, P. Gladkikh NSC/KIPT, Kharkov, Ukraine T. Omori, J. Urakawa, K. Yokoya KEK, Ibaraki, Japan
	The generation of polarized positrons for future colliders based on Compton storage rings is a promising method. A challenging key ingredient of this method is the necessary quasi-continuous positron injection into a stacking ring. The ordinary methods of multi-turn injection are not appropriate for this purpose, because the required number of injection-turns is a few hundred, and the emittance of the injected positron bunches is large. This paper describes a possible solution based on 5 GeV superconducting stacking ring, where a novel method of the combined longitudinal and transverse injection process is used to stack positrons. The ring dynamic aperture allows to inject the positron beam with normalized emittance up to 2000 micrometers during a few hundred turns. The injection efficiency is larger than 90% in simulation. The number of the injection turns is only limited by the synchrotron radiation power. The ring lattice and the results of injection simulations are presented.

TUPC073	Emittance Variation Dependence on Resonance Extraction Parameters at ELSA	emittance, extraction, resonance, sextupole	1168
	S. Zander, O. Boldt, F. Frommberger, W. Hillert, O. Preisner ELSA, Bonn, Germany
	Funding: Funded by the DFG within the SFB / TR 16. The Electron Stretcher Facility ELSA consists of several accelerator stages, the last one being a stretcher ring providing a beam of polarized electrons with an energy of up to 3.5~GeV. In order to guarantee a high duty cycle, a slow extraction via a third integer resonance is applied to the stretcher ring. The emittance of the extracted beam as well as the efficiency of the extraction process depend on different parameters as the sextupole strength being necessary for the excitation of the third integer resonance or the adjusted tune. In order to optimize the quality of the extracted beam, an accurate comprehension of the influence of these parameters is indispensable. Beam profiles are detected using dedicated synchrotron light monitors optimized for low intensities. The emittance was investigated by the method of quadrupole scan. The experimental studies are accompanied by numerical simulation studies. The results of the change of the emittance depending on different resonance extraction setups obtained by the experimental as well as by the theoretical studies will be presented.

TUPS013	Development of the H0 Dump Branch Duct for the Additional Collimation System in J-PARC RCS	shielding, collimation, beam-losses, vacuum	1545
	M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	For the new collimation system in the J-PARC RCS, we have the H0 branch duct installed at the dump septum magnet remodeled. This new branch duct is made of the two kinds of the stainless steels as follows; austenitic stainless steel, SUS316L and ferritic stainless steel, SUS430. In order to research on the property of the SUS430, test ducts were made in various heat-treating condition. In this presentation, we report the design of the new H0 branch duct and the study results with the test ducts.

TUPS033	Foil Scattering Loss Mitigation by the Additional Collimation System of J-PARC RCS	injection, collimation, vacuum, scattering	1605
	K. Yamamoto, H. Harada, J. Kamiya, Y. Yamazaki, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	In the RCS, the significant losses were observed at the branch of H0 dump line and the Beam Position Monitor which was put at the downstream of the H0 dump branch duct. From the beam study, we were certain that these losses were caused by the scattering of the injection and circulating beam at the charge exchange injection foil. In order to mitigate these losses, we started to develop a new collimation system in the H0 branch duct. We presents a overview of this new collimation system.

WEPC002	RF Separator and Septum Layout Concepts for Simultaneous Beams to RIB and FEL Users at ARIEL	linac, dipole, FEL, electron	1998
	Y.-C. Chao, C. Gong, S.R. Koscielniak TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	A ½ MW capable CW electron linac is being designed and constructed at TRIUMF in support of the existing Rare Isotope Beam program. In the simplest configuration, the beam makes a single pass through three cryomodules to the RIB production targets. However, after the construction of a recirculation path, beam could make a second pass through two cryomodules with the RF phase advance adjusted to give energy recovery. Here it is proposed to time-interleave two bunch trains, and via an RF separator and septum, to direct one single-pass train to RIB production and the second train through the energy recovery ring that contains an IR FEL. It is also the intention, in single user mode, to use the ring as an energy doubler. This paper describes the RF separation scheme and options for the extraction optics that satisfy the requirements of “simultaneous” beams to two users.

WEPC008	Optics for the Beam Switchyard at the European XFEL	kicker, undulator, quadrupole, extraction	2016
	N. Golubeva, V. Balandin, W. Decking DESY, Hamburg, Germany
	The European XFEL is planed as a multi-user facility with the possibility to distribute electron bunches of one beam pulse to different beamlines. The initial stage foresees two electron beamlines each serving its own set of undulators. The later addition of a third beamline is also considered in the design of the distribution system. In addition, the integration of the transport line to the beam abortion dump allows a flexible selection of the bunch repetition pattern for each beamline. The beam extraction, both in undulator beamlines and in the beamline to the dump, will be realized with fast kickers and a Lambertson septum. In this paper we describe the magnet lattice of the deflection arcs with simultaneous horizontal and vertical dispersions and the beam optics of the beam switchyard.

WEPC016	Amplitude Dependent Orbit Shift and its Effect on Beam Injection	injection, betatron, sextupole, synchrotron	2040
	Y. Shoji LASTI, Hyogo, Japan T. Nakamura, J. Schimizu, M. Takao JASRI/SPring-8, Hyogo-ken, Japan
	The betatron oscillation amplitude dependent orbit shift was measured at the electron storage ring, NewSUBARU. The result roughly agreed with the theoretical calculation. The effect of this shift on the beam injection is discussed using parameters of NewSUBARU and SPring-8. Generally there exists a better side for the injection, the inner side or the outer side of the ring, which depends on the sign of the orbit shift at the injection septum. In case of the NewSUBARU, the beam is injected from the outer side and the shift is positive. The effective thickness of the septum is reduced by the large oscillation amplitude of the injected beam. On the other hand at SPring-8, the beam is injected from the inner side of the ring while the orbit shift is negative. This means that the two rings are using better side for the injection.

WEPC056	Beam Test of Slow Extraction from the ESR	extraction, resonance, sextupole, ion	2142
	A. Dolinskii, C. Dimopoulou, O.E. Gorda, S.A. Litvinov, F. Nolden, M. Steck GSI, Darmstadt, Germany
	In the frame of a dedicated ESR machine development the conventional third order resonant slow extraction was theoretically investigated and experimentally tested. The possibility to extract a beam from the ESR by preparing a resonant closed orbit, which has strong nonlinear characteristics, was demonstrated. A third-integer resonance slow extraction has been adopted for the 100 MeV/u Ar beam.

WEPO006	Suppression of Leakage Fields from DC Magnets in J-PARC 3 GeV RCS	shielding, beam-losses, extraction, vacuum	2412
	M. Yoshimoto, H. Harada, N. Hayashi, H. Hotchi, M. Kinsho, P.K. Saha, K. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	In the J-PARC 3 GeV RCS, we found that DC leakage fields from the extraction beam line significantly affected the beam. For this issue, we installed additional shields and got the 40% reduction of the DC leakage field. Thus the circulating beam loss was successfully reduced. In this presentation, we report the detail of the shield structure and the results of the beam studies.

WEPS085	Deveopment of the IBA-JINR Cyclotron C235-V3 for Dmitrovgrad Hospital Center of the Proton Therapy	proton, cyclotron, extraction, betatron	2706
	E. Syresin, G.A. Karamysheva, M.Y. Kazarinov, S.A. Kostromin, N.A. Morozov, A.G. Olshevsky, V.M. Romanov, E. Samsonov, N.G. Shakun, G. Shirkov, S.G. Shirkov JINR, Dubna, Moscow Region, Russia M. Abs, A. Blondin, P. Cahay, Y. Jongen, W.J.G.M. Kleeven, S. Zaremba IBA, Louvain-la-Neuve, Belgium
	The approval of the Dmitrovgrad project - the first Russian hospital center of the proton therapy was announced in 2010. The JINR-IBA collaboration have developed and constructed the proton cyclotron C235-V3 for this center. We plan to assemble this cyclotron in JINR in 2011 and perform tests with the extracted proton beam in 2012. This cyclotron is an essentially modified version of IBA C235 cyclotron. Modification of the extraction system is aim of new C235-V3 cyclotron. The new extraction system was constructed and tested. The experimentally measured extraction efficiency was improved from 60% for the old system to 77% for the new one. The new field mapping system was developed for the C235-V3 cyclotron. It system consists of the axial field mapping system and an additional system applied for radial field Br measurements. One of the goals of the cyclotron improvement is the modification of the sector spiral angle for reducing of coherent beam losses at acceleration. The coherent beam displacement from the median plane is defined by the vertical betatron tune Qz. An increase of the vertical betatron tune permits to reduce the coherent losses at proton acceleration.

WEPS096	Injection Energy Recovery of J-PARC RCS	power-supply, injection, beam-losses, impedance	2730
	N. Hayashi, H. Hotchi, J. Kamiya, P.K. Saha, T. Takayanagi, K. Yamamoto, M. Yamamoto, Y. Yamazaki JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	The J-PARC RCS is a high beam power Rapid-Cycling Synchrotron (RCS). The original designed injection energy is 400MeV, although presently it is 181MeV, and its beam power is limited to 0.6MW. Works to recover the Linac energy are ongoing and injection magnets power supplies upgrade are required in the RCS. In order to achieve 1MW designed beam power, new instrumentation is also planned simultaneously. Activities related injection energy recovery in the J-PARC RCS is presented.

WEPS099	Physics Design of CSNS RCS Injection and Extraction System	extraction, injection, kicker, emittance	2739
	J. Qiu, N. Huang, J. Tang, S. Wang IHEP Beijing, Beijing, People's Republic of China
	In this paper, the injection and extraction system design for CSNS RCS are discussed. The injection system is designed to place all the injection devices in one uninterrupted long drift in one of the four dispersion free straight sections. Painting bumper magnets are used for both horizontal and vertical phase space painting. The beam extraction process from the CSNS RCS is a single turn two step process, requiring a group of kickers and a Lambertson septum magnet.

WEPZ015	Staging in Two Beam Dielectric Wakefield Accelerators	cavity, acceleration, wakefield, kicker	2802
	J.G. Power, M.E. Conde, W. Gai, C.-J. Jing ANL, Argonne, USA
	Funding: The work is supported by the U.S. Department of Energy under Contract No. DE-AC02-06CH11357 with Argonne National Laboratory. A new experimental program to demonstrate staging in a two beam dielectric wakefield accelerator (DWA) is being planned at the Argonne Wakefield Accelerator facility. DWA uses a drive beam to generate acceleration fields to accelerate a main beam and is one of the most promising advanced acceleration methods being pursued for a future high-energy physics linear collider. Staging is the ability to use two accelerating modules back to back to accelerate a charged particle bunch and it is one of basic requirements of any acceleration method. In this paper, a new beamline design consisting of a fast kicker to pick pulses from the drive bunch train and deliver them to the individual acceleration modules will be presented.

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

THPS033	Skew Quadrupole Effects on Multi-turn injection Efficiency in the SIS18	quadrupole, injection, emittance, coupling	3490
	W.M. Daqa, I. Hofmann, J. Struckmeier GSI, Darmstadt, Germany
	Funding: DAAD ( Deutscher Akademischer Austausch Dienst) One goal of the SIS18 upgrade scheme is concerned about improving the multi-turn injection (MTI) efficiency, in order to reach the required intensities at the targets and to operate effectively as a booster for SIS100. To improve the limitation of the MTI scheme, there were successful attempts in AGS and PS boosters, to use the skew injection scheme and later it was suggested for SIS18. The strength of the skew quadrupoles is optimized together with the horizontal tune, the difference in horizontal to vertical tunes, the incoming beam parameters and the geometrical limitation of SIS lattice. A good optimization implies the emittance exchange, due to linear coupling, to take place partially and just before the return of the beamlet back to its original position at the septum. The present work was done by simulation using the code PARMTRA and compared with measurements. The results show that, depending on the working point, the skew injection scheme can improve the MTI efficiency from 2% up to 12%, taking into account the loss on the septum from inside and on the vertical acceptance.

THPS035	Collimator Upgrade Plan of the J-PARC Main Ring	radiation, injection, collimation, beam-losses	3496
	M.J. Shirakata, K. Ishii, C. Kubota, T. Oogoe, J. Takano KEK, Ibaraki, Japan Y. Kuniyasu MELCO SC, Tsukuba, Japan Y. Takiyama JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	A halo collimation system is prepared in the middle of injection-straight section in order to localize the beam loss occurred in main ring. It consists of three collimator units. The first unit scatters halo components, and the other two units work as halo catchers. The permitted amount of beam losses in the collimator section is designed to be 450 W at the present. The upgrade plan of halo collimation system is running in order to achieve about ten times larger beam loss capability for high-power beam operation. The collimator upgrade is planned by installing a new collimator set and radiation shields which cover the collimator section. New collimator units are designed to be able to line-out the jaw with a part of radiation shield including the mechanical devices. The design work of collimator units and radiation shields is presented in this report.

THPS047	New Injection and Extraction at CRYRING for FLAIR	extraction, injection, ion, kicker	3529
	A. Simonsson, L. Brännholm, S. Das, A. Källberg, P. Löfgren, A. Paal, J. Sjöholm MSL, Stockholm, Sweden H. Danared ESS, Lund, Sweden D. Reistad Intégro Utbildnings AB, Sigtuna, Sweden
	As a preparation for a future transfer of CRYRING to FLAIR at FAIR in Darmstadt, Germany, we have installed and tested a slow extraction system. At FLAIR CRYRING will be used for deceleration of antiprotons from 30 MeV to 0.3 MeV. The tests of the slow extraction show that the beam can be extracted during 2 s with 30-60% efficiency and with rather constant amplitude, apart from noise from 50 Hz harmonics. A new injection system has also been designed. It will be able to inject 30 MeV antiprotons from NESR as well as 0.3 MeV/u ions created in a separate ion source and accelerated in an RFQ.

THPS048	Design of Electrostatic Septa and Fast Deflector for MedAustron	power-supply, cathode, synchrotron, injection	3532
	J. Borburgh, T. Fowler, A. Prost CERN, Geneva, Switzerland T. Kramer, T. Stadlbauer EBG MedAustron, Wr. Neustadt, Austria
	For the MedAustron facility, under construction in Wiener Neustadt, three electric field deflectors are developed in collaboration with CERN. A fast deflector is used in the Low Energy Beam Transfer line to chop the beam. The chopped beam is swept onto a Faraday cup for measurement purposes and to stop beam being sent towards the synchrotron. Electrostatic septa are used for the multi turn injection of protons and ions as well as for the slow extraction from the synchrotron. Novel design features for MedAustron include an inversed cathode/anode support and high voltage feedthroughs rated at 150 kV. The possibility for a higher voltage will significantly improve the conditioning process of the septa surfaces. This paper describes the requirements of these devices as well as the mechanical design and strategies adopted for their power supplies.

THPS049	Feasibility Study of a CERN PS Injection at 2 GeV	injection, optics, kicker, vacuum	3535
	J. Borburgh, S. Aumon, W. Bartmann, S.S. Gilardoni, B. Goddard, L. Sermeus, R.R. Steerenberg CERN, Geneva, Switzerland
	In the framework of the potential CERN PS Booster (PSB) energy upgrade, a study was initiated to look into the possibilities and constraints to inject protons into the PS at kinetic energies up to 2 GeV, for LHC type beams and other (high intensity) beams. This paper highlights the identified bottlenecks and potential solutions and addresses the resulting requirements for the hardware in the transfer line and injection region of the PS. In conjunction with the proposed upgrade of the PSB-PS transfer line hardware the optics can be changed for different cycles. Optics solutions optimized for the different requirements of LHC type and other beams are presented.

THPS054	Injection and Extraction Considerations for a 2 GeV RCS at CERN	extraction, injection, quadrupole, kicker	3550
	W. Bartmann, B. Balhan, J. Borburgh, L. Ducimetière, M. Fitterer, B. Goddard, L. Sermeus CERN, Geneva, Switzerland
	Conceptual studies have been made for a 2 GeV RCS at CERN as a possible replacement of the four-ring PS Booster. The lattice design has to accommodate suitable straight sections for a 160 MeV H⁻ charge exchange injection system, and for a 2 GeV fast extraction system. The design constraints for the injection and extraction systems are described, together with the proposed concepts and potential equipment limitations. In particular, the features of different possible H⁻ injection configurations are compared.

Paper

Title

Other Keywords

Page

MOPZ004

Studies for the PRISM FFAG Ring for the Next Generation Muon to Electron Conversion Experiment

injection, kicker, electron, extraction

826

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

High intensity and high quality muon beams are needed for the next generation lepton flavour violation experiments. Such beams can be produced by sending a short proton pulse to a pion production target, capturing the pions and performing RF phase rotation on the resulting muon beam in an FFAG ring. Such a solution was proposed for the PRISM project and this paper summarizes its current status. In particular the PRISM task force was created to address the accelerator and detector issues that need to be solved in order to realise the PRISM experiment. Alternative designs for the PRISM FFAG ring are discussed and their performance compared. The injection/extraction systems and matching to the solenoid channels upstream and downstream of the FFAG ring are presented. The future direction for the study will be outlined.

MOPZ029

Aperture Windows in High-Gradient Cavities for Accelerating Low-Energy Muons

cavity, linac, target, vacuum

862

S.S. Kurennoy, A.J. Jason, W.M. Tuzel
LANL, Los Alamos, New Mexico, USA

A high-gradient linear accelerator for accelerating low-energy muons and pions in a strong solenoidal magnetic field has been proposed for homeland defense and industrial applications*. The acceleration starts immediately after collection of pions from a target in a solenoidal magnetic field and brings muons to a kinetic energy of about 200 MeV over a distance of the order of 10 m. At this energy, both ionization cooling of the muon beam and its further acceleration become feasible. A normal-conducting linac with external-solenoid focusing can provide the required large beam acceptances. The linac consists of independently fed zero-mode (TM010) RF cavities with wide beam apertures closed by thin conducting windows. The high gradients lead to significant heat deposition on the aperture windows. Here we explore options for the edge-cooled thin windows in the zero-mode cavities. Electromagnetic and thermal-stress computations are complemented by thermal-test experiments to select the best solution for the aperture windows.
* S.S. Kurennoy, A.J. Jason, H. Miyadera, “Large-Acceptance Linac for Accelerating Low-Energy Muons,” Proc. of IPAC10, p. 3518 (2010).

MOPZ038

EMMA Injection and Extraction

injection, extraction, dipole, kicker

883

B.D. Muratori, J.K. Jones
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
Y. Giboudot
Brunel University, Middlesex, United Kingdom
D.J. Holder
The University of Liverpool, Liverpool, United Kingdom

EMMA (Electron Machine with Many Applications) is a prototype non-scaling electron FFAG hosted at Daresbury Laboratory. NS-FFAGs related to EMMA have an unprecedented potential for medical accelerators for carbon and proton hadron therapy. They could also be used as the accelerator for a sub-critical reactor. We summarize the design and commissioning of both the injection and extraction lines for this machine. In particular, we look at the commissioning challenges of injection and extraction.

TUYB01

First Results from the EMMA Experiment

acceleration, electron, cavity, injection

951

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

Report on first commissioning results and operational experience with EMMA, the world's first nonscaling FFAG. In particular review the effect of resonance crossing, and the efficiency of serpentine acceleration.

Slides TUYB01 [9.201 MB]

TUPC053

Superconducting Positron Stacking Ring for CLIC

positron, injection, damping, synchrotron

1117

F. Zimmermann, L. Rinolfi
CERN, Geneva, Switzerland
E.V. Bulyak, P. Gladkikh
NSC/KIPT, Kharkov, Ukraine
T. Omori, J. Urakawa, K. Yokoya
KEK, Ibaraki, Japan

The generation of polarized positrons for future colliders based on Compton storage rings is a promising method. A challenging key ingredient of this method is the necessary quasi-continuous positron injection into a stacking ring. The ordinary methods of multi-turn injection are not appropriate for this purpose, because the required number of injection-turns is a few hundred, and the emittance of the injected positron bunches is large. This paper describes a possible solution based on 5 GeV superconducting stacking ring, where a novel method of the combined longitudinal and transverse injection process is used to stack positrons. The ring dynamic aperture allows to inject the positron beam with normalized emittance up to 2000 micrometers during a few hundred turns. The injection efficiency is larger than 90% in simulation. The number of the injection turns is only limited by the synchrotron radiation power. The ring lattice and the results of injection simulations are presented.

TUPC073

Emittance Variation Dependence on Resonance Extraction Parameters at ELSA

emittance, extraction, resonance, sextupole

1168

S. Zander, O. Boldt, F. Frommberger, W. Hillert, O. Preisner
ELSA, Bonn, Germany

Funding: Funded by the DFG within the SFB / TR 16.
The Electron Stretcher Facility ELSA consists of several accelerator stages, the last one being a stretcher ring providing a beam of polarized electrons with an energy of up to 3.5~GeV. In order to guarantee a high duty cycle, a slow extraction via a third integer resonance is applied to the stretcher ring. The emittance of the extracted beam as well as the efficiency of the extraction process depend on different parameters as the sextupole strength being necessary for the excitation of the third integer resonance or the adjusted tune. In order to optimize the quality of the extracted beam, an accurate comprehension of the influence of these parameters is indispensable. Beam profiles are detected using dedicated synchrotron light monitors optimized for low intensities. The emittance was investigated by the method of quadrupole scan. The experimental studies are accompanied by numerical simulation studies. The results of the change of the emittance depending on different resonance extraction setups obtained by the experimental as well as by the theoretical studies will be presented.

TUPS013

Development of the H0 Dump Branch Duct for the Additional Collimation System in J-PARC RCS

shielding, collimation, beam-losses, vacuum

1545

M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

For the new collimation system in the J-PARC RCS, we have the H0 branch duct installed at the dump septum magnet remodeled. This new branch duct is made of the two kinds of the stainless steels as follows; austenitic stainless steel, SUS316L and ferritic stainless steel, SUS430. In order to research on the property of the SUS430, test ducts were made in various heat-treating condition. In this presentation, we report the design of the new H0 branch duct and the study results with the test ducts.

TUPS033

Foil Scattering Loss Mitigation by the Additional Collimation System of J-PARC RCS

injection, collimation, vacuum, scattering

1605

K. Yamamoto, H. Harada, J. Kamiya, Y. Yamazaki, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

In the RCS, the significant losses were observed at the branch of H0 dump line and the Beam Position Monitor which was put at the downstream of the H0 dump branch duct. From the beam study, we were certain that these losses were caused by the scattering of the injection and circulating beam at the charge exchange injection foil. In order to mitigate these losses, we started to develop a new collimation system in the H0 branch duct. We presents a overview of this new collimation system.

WEPC002

RF Separator and Septum Layout Concepts for Simultaneous Beams to RIB and FEL Users at ARIEL

linac, dipole, FEL, electron

1998

Y.-C. Chao, C. Gong, S.R. Koscielniak
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

A ½ MW capable CW electron linac is being designed and constructed at TRIUMF in support of the existing Rare Isotope Beam program. In the simplest configuration, the beam makes a single pass through three cryomodules to the RIB production targets. However, after the construction of a recirculation path, beam could make a second pass through two cryomodules with the RF phase advance adjusted to give energy recovery. Here it is proposed to time-interleave two bunch trains, and via an RF separator and septum, to direct one single-pass train to RIB production and the second train through the energy recovery ring that contains an IR FEL. It is also the intention, in single user mode, to use the ring as an energy doubler. This paper describes the RF separation scheme and options for the extraction optics that satisfy the requirements of “simultaneous” beams to two users.

WEPC008

Optics for the Beam Switchyard at the European XFEL

kicker, undulator, quadrupole, extraction

2016

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

The European XFEL is planed as a multi-user facility with the possibility to distribute electron bunches of one beam pulse to different beamlines. The initial stage foresees two electron beamlines each serving its own set of undulators. The later addition of a third beamline is also considered in the design of the distribution system. In addition, the integration of the transport line to the beam abortion dump allows a flexible selection of the bunch repetition pattern for each beamline. The beam extraction, both in undulator beamlines and in the beamline to the dump, will be realized with fast kickers and a Lambertson septum. In this paper we describe the magnet lattice of the deflection arcs with simultaneous horizontal and vertical dispersions and the beam optics of the beam switchyard.

WEPC016

Amplitude Dependent Orbit Shift and its Effect on Beam Injection

injection, betatron, sextupole, synchrotron

2040

Y. Shoji
LASTI, Hyogo, Japan
T. Nakamura, J. Schimizu, M. Takao
JASRI/SPring-8, Hyogo-ken, Japan

The betatron oscillation amplitude dependent orbit shift was measured at the electron storage ring, NewSUBARU. The result roughly agreed with the theoretical calculation. The effect of this shift on the beam injection is discussed using parameters of NewSUBARU and SPring-8. Generally there exists a better side for the injection, the inner side or the outer side of the ring, which depends on the sign of the orbit shift at the injection septum. In case of the NewSUBARU, the beam is injected from the outer side and the shift is positive. The effective thickness of the septum is reduced by the large oscillation amplitude of the injected beam. On the other hand at SPring-8, the beam is injected from the inner side of the ring while the orbit shift is negative. This means that the two rings are using better side for the injection.

WEPC056

Beam Test of Slow Extraction from the ESR

extraction, resonance, sextupole, ion

2142

A. Dolinskii, C. Dimopoulou, O.E. Gorda, S.A. Litvinov, F. Nolden, M. Steck
GSI, Darmstadt, Germany

In the frame of a dedicated ESR machine development the conventional third order resonant slow extraction was theoretically investigated and experimentally tested. The possibility to extract a beam from the ESR by preparing a resonant closed orbit, which has strong nonlinear characteristics, was demonstrated. A third-integer resonance slow extraction has been adopted for the 100 MeV/u Ar beam.

WEPO006

Suppression of Leakage Fields from DC Magnets in J-PARC 3 GeV RCS

shielding, beam-losses, extraction, vacuum

2412

M. Yoshimoto, H. Harada, N. Hayashi, H. Hotchi, M. Kinsho, P.K. Saha, K. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

In the J-PARC 3 GeV RCS, we found that DC leakage fields from the extraction beam line significantly affected the beam. For this issue, we installed additional shields and got the 40% reduction of the DC leakage field. Thus the circulating beam loss was successfully reduced. In this presentation, we report the detail of the shield structure and the results of the beam studies.

WEPS085

Deveopment of the IBA-JINR Cyclotron C235-V3 for Dmitrovgrad Hospital Center of the Proton Therapy

proton, cyclotron, extraction, betatron

2706

E. Syresin, G.A. Karamysheva, M.Y. Kazarinov, S.A. Kostromin, N.A. Morozov, A.G. Olshevsky, V.M. Romanov, E. Samsonov, N.G. Shakun, G. Shirkov, S.G. Shirkov
JINR, Dubna, Moscow Region, Russia
M. Abs, A. Blondin, P. Cahay, Y. Jongen, W.J.G.M. Kleeven, S. Zaremba
IBA, Louvain-la-Neuve, Belgium

The approval of the Dmitrovgrad project - the first Russian hospital center of the proton therapy was announced in 2010. The JINR-IBA collaboration have developed and constructed the proton cyclotron C235-V3 for this center. We plan to assemble this cyclotron in JINR in 2011 and perform tests with the extracted proton beam in 2012. This cyclotron is an essentially modified version of IBA C235 cyclotron. Modification of the extraction system is aim of new C235-V3 cyclotron. The new extraction system was constructed and tested. The experimentally measured extraction efficiency was improved from 60% for the old system to 77% for the new one. The new field mapping system was developed for the C235-V3 cyclotron. It system consists of the axial field mapping system and an additional system applied for radial field Br measurements. One of the goals of the cyclotron improvement is the modification of the sector spiral angle for reducing of coherent beam losses at acceleration. The coherent beam displacement from the median plane is defined by the vertical betatron tune Qz. An increase of the vertical betatron tune permits to reduce the coherent losses at proton acceleration.

WEPS096

Injection Energy Recovery of J-PARC RCS

power-supply, injection, beam-losses, impedance

2730

N. Hayashi, H. Hotchi, J. Kamiya, P.K. Saha, T. Takayanagi, K. Yamamoto, M. Yamamoto, Y. Yamazaki
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

The J-PARC RCS is a high beam power Rapid-Cycling Synchrotron (RCS). The original designed injection energy is 400MeV, although presently it is 181MeV, and its beam power is limited to 0.6MW. Works to recover the Linac energy are ongoing and injection magnets power supplies upgrade are required in the RCS. In order to achieve 1MW designed beam power, new instrumentation is also planned simultaneously. Activities related injection energy recovery in the J-PARC RCS is presented.

WEPS099

Physics Design of CSNS RCS Injection and Extraction System

extraction, injection, kicker, emittance

2739

J. Qiu, N. Huang, J. Tang, S. Wang
IHEP Beijing, Beijing, People's Republic of China

In this paper, the injection and extraction system design for CSNS RCS are discussed. The injection system is designed to place all the injection devices in one uninterrupted long drift in one of the four dispersion free straight sections. Painting bumper magnets are used for both horizontal and vertical phase space painting. The beam extraction process from the CSNS RCS is a single turn two step process, requiring a group of kickers and a Lambertson septum magnet.

WEPZ015

Staging in Two Beam Dielectric Wakefield Accelerators

cavity, acceleration, wakefield, kicker

2802

J.G. Power, M.E. Conde, W. Gai, C.-J. Jing
ANL, Argonne, USA

Funding: The work is supported by the U.S. Department of Energy under Contract No. DE-AC02-06CH11357 with Argonne National Laboratory.
A new experimental program to demonstrate staging in a two beam dielectric wakefield accelerator (DWA) is being planned at the Argonne Wakefield Accelerator facility. DWA uses a drive beam to generate acceleration fields to accelerate a main beam and is one of the most promising advanced acceleration methods being pursued for a future high-energy physics linear collider. Staging is the ability to use two accelerating modules back to back to accelerate a charged particle bunch and it is one of basic requirements of any acceleration method. In this paper, a new beamline design consisting of a fast kicker to pick pulses from the drive bunch train and deliver them to the individual acceleration modules will be presented.

THPC140

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

kicker, injection, vacuum, storage-ring

3215

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

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

THPS033

Skew Quadrupole Effects on Multi-turn injection Efficiency in the SIS18

quadrupole, injection, emittance, coupling

3490

W.M. Daqa, I. Hofmann, J. Struckmeier
GSI, Darmstadt, Germany

Funding: DAAD ( Deutscher Akademischer Austausch Dienst)
One goal of the SIS18 upgrade scheme is concerned about improving the multi-turn injection (MTI) efficiency, in order to reach the required intensities at the targets and to operate effectively as a booster for SIS100. To improve the limitation of the MTI scheme, there were successful attempts in AGS and PS boosters, to use the skew injection scheme and later it was suggested for SIS18. The strength of the skew quadrupoles is optimized together with the horizontal tune, the difference in horizontal to vertical tunes, the incoming beam parameters and the geometrical limitation of SIS lattice. A good optimization implies the emittance exchange, due to linear coupling, to take place partially and just before the return of the beamlet back to its original position at the septum. The present work was done by simulation using the code PARMTRA and compared with measurements. The results show that, depending on the working point, the skew injection scheme can improve the MTI efficiency from 2% up to 12%, taking into account the loss on the septum from inside and on the vertical acceptance.

THPS035

Collimator Upgrade Plan of the J-PARC Main Ring

radiation, injection, collimation, beam-losses

3496

M.J. Shirakata, K. Ishii, C. Kubota, T. Oogoe, J. Takano
KEK, Ibaraki, Japan
Y. Kuniyasu
MELCO SC, Tsukuba, Japan
Y. Takiyama
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

A halo collimation system is prepared in the middle of injection-straight section in order to localize the beam loss occurred in main ring. It consists of three collimator units. The first unit scatters halo components, and the other two units work as halo catchers. The permitted amount of beam losses in the collimator section is designed to be 450 W at the present. The upgrade plan of halo collimation system is running in order to achieve about ten times larger beam loss capability for high-power beam operation. The collimator upgrade is planned by installing a new collimator set and radiation shields which cover the collimator section. New collimator units are designed to be able to line-out the jaw with a part of radiation shield including the mechanical devices. The design work of collimator units and radiation shields is presented in this report.

THPS047

New Injection and Extraction at CRYRING for FLAIR

extraction, injection, ion, kicker

3529

A. Simonsson, L. Brännholm, S. Das, A. Källberg, P. Löfgren, A. Paal, J. Sjöholm
MSL, Stockholm, Sweden
H. Danared
ESS, Lund, Sweden
D. Reistad
Intégro Utbildnings AB, Sigtuna, Sweden

As a preparation for a future transfer of CRYRING to FLAIR at FAIR in Darmstadt, Germany, we have installed and tested a slow extraction system. At FLAIR CRYRING will be used for deceleration of antiprotons from 30 MeV to 0.3 MeV. The tests of the slow extraction show that the beam can be extracted during 2 s with 30-60% efficiency and with rather constant amplitude, apart from noise from 50 Hz harmonics. A new injection system has also been designed. It will be able to inject 30 MeV antiprotons from NESR as well as 0.3 MeV/u ions created in a separate ion source and accelerated in an RFQ.

THPS048

Design of Electrostatic Septa and Fast Deflector for MedAustron

power-supply, cathode, synchrotron, injection

3532

J. Borburgh, T. Fowler, A. Prost
CERN, Geneva, Switzerland
T. Kramer, T. Stadlbauer
EBG MedAustron, Wr. Neustadt, Austria

For the MedAustron facility, under construction in Wiener Neustadt, three electric field deflectors are developed in collaboration with CERN. A fast deflector is used in the Low Energy Beam Transfer line to chop the beam. The chopped beam is swept onto a Faraday cup for measurement purposes and to stop beam being sent towards the synchrotron. Electrostatic septa are used for the multi turn injection of protons and ions as well as for the slow extraction from the synchrotron. Novel design features for MedAustron include an inversed cathode/anode support and high voltage feedthroughs rated at 150 kV. The possibility for a higher voltage will significantly improve the conditioning process of the septa surfaces. This paper describes the requirements of these devices as well as the mechanical design and strategies adopted for their power supplies.

THPS049

Feasibility Study of a CERN PS Injection at 2 GeV

injection, optics, kicker, vacuum

3535

J. Borburgh, S. Aumon, W. Bartmann, S.S. Gilardoni, B. Goddard, L. Sermeus, R.R. Steerenberg
CERN, Geneva, Switzerland

In the framework of the potential CERN PS Booster (PSB) energy upgrade, a study was initiated to look into the possibilities and constraints to inject protons into the PS at kinetic energies up to 2 GeV, for LHC type beams and other (high intensity) beams. This paper highlights the identified bottlenecks and potential solutions and addresses the resulting requirements for the hardware in the transfer line and injection region of the PS. In conjunction with the proposed upgrade of the PSB-PS transfer line hardware the optics can be changed for different cycles. Optics solutions optimized for the different requirements of LHC type and other beams are presented.

THPS054

Injection and Extraction Considerations for a 2 GeV RCS at CERN

extraction, injection, quadrupole, kicker

3550

W. Bartmann, B. Balhan, J. Borburgh, L. Ducimetière, M. Fitterer, B. Goddard, L. Sermeus
CERN, Geneva, Switzerland

Conceptual studies have been made for a 2 GeV RCS at CERN as a possible replacement of the four-ring PS Booster. The lattice design has to accommodate suitable straight sections for a 160 MeV H⁻ charge exchange injection system, and for a 2 GeV fast extraction system. The design constraints for the injection and extraction systems are described, together with the proposed concepts and potential equipment limitations. In particular, the features of different possible H⁻ injection configurations are compared.