IPAC2015 - List of Keywords (Windows)

Paper	Title	Other Keywords	Page
MOAD2	RF Breakdown of 805 MHz Cavities in Strong Magnetic Fields	cavity, operation, controls, klystron	53
	D.L. Bowring, A.V. Kochemirovskiy, M.A. Leonova, A. Moretti, M.A. Palmer, D.W. Peterson, K. Yonehara Fermilab, Batavia, Illinois, USA B.T. Freemire IIT, Chicago, Illinois, USA A.A. Haase SLAC, Menlo Park, California, USA P.G. Lane, Y. Torun Illinois Institute of Technology, Chicago, Illinois, USA D. Stratakis BNL, Upton, Long Island, New York, USA
	Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures in the presence of strong magnetic fields. We have measured the breakdown rate in several RF cavities operating at several frequencies. Cavities operating within solenoidal magnetic fields B > 0.25 T show an increased RF breakdown rate at lower gradients compared with similar operation when B = 0 T. Ultimately, this breakdown behavior limits the maximum safe operating gradient of the cavity. Beyond ionization cooling, this issue affects the design of photoinjectors and klystrons, among other applications. We have built an 805 MHz pillbox-type RF cavity to serve as an experimental testbed for this phenomenon. This cavity is designed to study the problem of RF breakdown in strong magnetic fields using various cavity materials and surface treatments, and with precise control over sources of systematic error. We present results from tests in which the cavity was run with all copper surfaces in a variety of magnetic fields.
	Slides MOAD2 [10.792 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOAD2
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MOPWI020	Development of Simple Tracking Libraries for ALS-U	lattice, simulation, framework, dynamic-aperture	1192
	H. Nishimura, D. Robin, K. Song, C. Steier, C. Sun, W. Wan LBNL, Berkeley, California, USA
	Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 The conceptual lattice design study of a new diffraction-limited light source has become much more computer intensive than that for the 3rd-generation rings. We are in a process of upgrading our existing accelerator modeling and simulation libraries, Goemon* in C++ and a new version Tracy#, to fulfil such new demand. The C++ version has been actively used on the ALS HPC cluster for multi-objective optimization (MOGA) to optimize the ALS lattice, and recently for ALS-U*. This time, based on the current version in C#, we extracted its subset and ported it to C and C++. The routines are made thread-safe to enable OpenMP locally, and CPU-time profiling was extensively used to remove redundancies. The new refitting method of quad settings brought smooth switching from 5-dim to 6-dim. The data structure itself is simplified for the use on GPU that is based on our previous effort of tracking particles in GPU**. Tracy# itself is also upgraded to cooperate with these C/C++ versions. Their use from Python will be also mentioned. H. Nishimura, PAC01, 3066-3068. H. Nishimura, ICAP09. * C. Sun, et. al.,PAC11, 793-795. ** H. Tarawneh, et. al.,J.Phys.493 012020, 2014. *** H. Nishimura, et. al.,PAC11, 1764-1766.
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MOPWI027	Open XAL Control Room Experience	controls, software, optics, operation	1214
	C.P. Chu, D.G. Maxwell, Y. Zhang FRIB, East Lansing, Michigan, USA C.K. Allen, T.A. Pelaia II, A.P. Shishlo ORNL, Oak Ridge, Tennessee, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy under Cooperative Agreement DE-SC0000661 and DE-AC05-00OR22725, the State of Michigan and Michigan State University. This paper reports the control room experience, lessons learned, and quick deployment approach for the Open XAL application environment. Open XAL is a java-based framework for building high-level accelerator applications, it is a major revision of the XAL framework which was developed at the Spallation Neutron Source (SNS). Open XAL is site neutral and may be deployed at multiple accelerator facilities. Currently, Open XAL is installed at SNS and at the Re-Accelerator facility of Michigan State University. At SNS we are in the final process of replacing the old XAL environment with Open XAL; we describe the upgrade process and our accelerator operations experience using Open XAL. At Michigan State, Open XAL has been tested during a cryomodule commissioning and result will be shown.
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WEPMA007	Experimental Study of Multipactor Suppression in Dielectric Materials	multipactoring, electron, vacuum, target	2753
	M. El Khaldi, W. Kaabi LAL, Orsay, France
	A novel coaxial resonator to investigate two-surface multipactor discharges on metal and dielectric surfaces in the gap region under vacuum conditions (~10^-8 mbar) has been designed and tested. The resonator is ~ 100 mm in length with an outer diameter of ~ 60 mm (internal dimensions). A pulsed RF source delivers up to 30 W average power over a wide frequency range 650-900 MHz to the RF resonator. The incident and reflected RF signals are monitored by calibrated RF diodes. An electron probe provides temporal measurements of the multipacting electron current with respect to the RF pulses. In this paper we compare and contrast the results from the RF power tests of the alumina (97.6% Al2O3) and quartz samples without a coating, “the non-coated samples” and the Alumina and quartz samples with a thick TiN coating in order to evaluate a home made sputtered titanium nitride (TiN) thin layers as a Multipactor suppressor. The effectiveness of this method is presented and discussed in the paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPMA007
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WEPHA020	Titanium Coating of Ceramics for Accelerator Applications	vacuum, cathode, electron, target	3148
	W. Vollenberg, P. Costa Pinto, B. Holliger, A. Sapountzis, M. Taborelli CERN, Geneva, Switzerland
	Titanium thin films can be deposited on ceramics, in particular alumina, without adherence problems. Even after air exposure their secondary electron yield is low compared to alumina and can be further reduced by conditioning or beam scrubbing. In addition, depending on the film thickness, titanium provides different surface resistances that fulfil requirements of ceramics in particle accelerators. Titanium thin films (MOhm square range) are used to suppress electron multipacting and evacuate charges from ceramic surfaces. Thicker films (5-25 Ω square range) are applied to lower the surface resistance so that the beam impedance is reduced. In this contribution, we present the results of a development aimed at coating 2-meter long alumina vacuum chambers with a uniform surface resistivity by a dedicated DC magnetron sputtering configuration.
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WEPTY015	Examination of Beryllium under Intense High Energy Proton Beam at CERN's HiRadMat Facility	experiment, target, proton, instrumentation	3289
	K. Ammigan, B.D. Hartsell, P. Hurh, R.M. Zwaska Fermilab, Batavia, Illinois, USA A.R. Atherton STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom M. Butcher, M. Calviani, M. Guinchard, R. Losito CERN, Geneva, Switzerland O. Caretta, T.R. Davenne, C.J. Densham, M.D. Fitton, P. Loveridge, J. O'Dell STFC/RAL, Chilton, Didcot, Oxon, United Kingdom V.I. Kuksenko, S.G. Roberts University of Oxford, Oxford, United Kingdom
	Funding: Work supported by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. Beryllium is extensively used in various accelerator beam lines and target facilities as material for beam windows, and to a lesser extent, as secondary particle production targets. With increasing beam intensities of future accelerator facilities, it is critical to understand the response of beryllium under extreme conditions to avoid compromising particle production efficiency by limiting beam parameters. As a result, the planned experiment at CERN’s HiRadMat facility will take advantage of the test facility’s tunable high intensity proton beam to probe and investigate the damage mechanisms of several grades of beryllium. The test matrix will consist of multiple arrays of thin discs of varying thicknesses as well as cylinders, each exposed to increasing beam intensities. Online instrumentations will acquire real time temperature, strain, and vibration data of the cylinders, while Post-Irradiation-Examination (PIE) of the discs will exploit advanced microstructural characterization and imaging techniques to analyze grain structures, crack morphology and surface evolution. Details on the experimental design, online measurements and planned PIE efforts are described in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY015
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WEPTY046	Progress on the MICE 201 MHz Cavities at LBNL	cavity, coupling, simulation, network	3378
	T.H. Luo, A.J. DeMello, A.R. Lambert, D. Li, S. Prestemon, S.P. Virostek LBNL, Berkeley, California, USA
	The international Muon Ionization Cooling Experiment aims to demonstrate the transverse cooling of amuon beam by ionization in energy absorbers. The final MICE cooling channel configuration has two RF modules, each housing a 201 MHz RF cavity used to compensate the longitudinal energy loss in the absorbers. The LBNL team has designed and fabricated all MICE RF cavities. The cavities will be post-processed and RF measured before being installed in the RF modules. We present the recent progress on this work, including the low level RF measurement on cavity body and Be windows, the electro-polishing (EP) on the cavity surface, the numerical simulation on cavity Be window detuning, and the ongoing mechanical designing work of cavity components.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY046
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WEPTY047	Thermal and Lorentz Force Analysis of Beryllium Windows for the Rectilinear Muon Cooling Channel	cavity, simulation, collider, emittance	3381
	T.H. Luo, D. Li, S.P. Virostek LBNL, Berkeley, California, USA D.L. Bowring Fermilab, Batavia, Illinois, USA R.B. Palmer, D. Stratakis BNL, Upton, Long Island, New York, USA
	Reduction of the 6-dimensional phase-space of a muon beam by several orders of magnitude is a key requirement for a Muon Collider. Recently, a 12-stage rectilinear ionization cooling channel has been proposed to achieve that goal. The channel consists of a series of low frequency (325 MHz-650 MHz) normal conducting pillbox cavities, which are enclosed within thin beryllium windows (foils) to increase shunt impedance and give a higher field on-axis for a given amount of power. These windows are subject to ohmic heating from RF currents and Lorentz force from the EM field in the cavity, both of which will produce out of plane displacements that can detune the cavity frequency. In this study, using the TEM3P code, we report on a detailed thermal and mechanical analysis for the actual Be windows used on a 325 MHz cavity in a vacuum ionization cooling rectilinear channel for a Muon Collider.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY047
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WEPTY054	Grid Window Tests on an 805-MHz Pillbox Cavity	cavity, scattering, radiation, controls	3393
	Y. Torun Illinois Institute of Technology, Chicago, Illlinois, USA A. Moretti Fermilab, Batavia, Illinois, USA
	Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program. Muon ionization cooling channel designs use pillbox shaped RF cavities for improved power efficiency and fine control over phasing of individual cavities. For minimum scattering of the muon beam, the ends should be made out of a small thickness of high radiation length material. Good electrical and thermal conductivity are required to reduce power dissipation and remove the heat efficiently. Thin curved beryllium windows with TiN coating have been used successfully in the past. We have built an alternative window set consisting of grids of tubes and tested these on a pillbox cavity previously used with both thin Be and thick Cu windows. The cavity was operated with a pair of grids as well as a single grid against a flat endplate.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY054
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WEPTY055	Installation and Commissioning of the MICE RF Module Prototype	cavity, vacuum, operation, coupling	3395
	Y. Torun, P.G. Lane Illinois Institute of Technology, Chicago, Illlinois, USA T.G. Anderson, D.L. Bowring, M. Chung, J.H. Gaynier, M.A. Leonova, A. Moretti, R.J. Pasquinelli, D.W. Peterson, R.P. Schultz Fermilab, Batavia, Illinois, USA A.J. DeMello, D. Li, S.P. Virostek LBNL, Berkeley, California, USA L. Somaschini INFN-Pisa, Pisa, Italy
	Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program. A special vacuum vessel prototype was built to house the first production 201 MHz RF cavity for the International Muon Ionization Cooling Experiment (MICE). The resulting prototype RF module has been assembled, instrumented, installed and commissioned at Fermilab's MuCool Test Area and the effort has provided valuable experience for the design of modules that will be used in the cooling channel for the experiment.
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THPF077	Proposal for a 72.75 MHz RFQ for the LINCE Accelerator Complex	rfq, cavity, simulation, pick-up	3861
	A.K. Orduz, A. Berjillos, C. Bonțoiu, J.A. Dueñas, I. Martel University of Huelva, Huelva, Spain A. Garbayo AVS, Elgoibar, Spain
	Funding: Work partially supported by the Spanish Government (MINECO-CDTI) under program FEDER INTERCONNECTA The low-energy part of the LINCE facility can be based on a 72.75MHz normal-conducting RFQ designed to give a 450 keV/u boost for A/Q=7 ions in about 5m length. The vanes have been electromagnetically designed to accommodate dedicated RF windows producing effective separation of the RFQ modes in an octagonal-shaped resonance chamber. This article outlines the optimization of the quality factor of the cavity by using numerical methods for electromagnetic calculations. Experimental results of RF test carried out on a prototype are also discussed.
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Paper

Title

Other Keywords

Page

MOAD2

RF Breakdown of 805 MHz Cavities in Strong Magnetic Fields

cavity, operation, controls, klystron

53

D.L. Bowring, A.V. Kochemirovskiy, M.A. Leonova, A. Moretti, M.A. Palmer, D.W. Peterson, K. Yonehara
Fermilab, Batavia, Illinois, USA
B.T. Freemire
IIT, Chicago, Illinois, USA
A.A. Haase
SLAC, Menlo Park, California, USA
P.G. Lane, Y. Torun
Illinois Institute of Technology, Chicago, Illinois, USA
D. Stratakis
BNL, Upton, Long Island, New York, USA

Ionization cooling of intense muon beams requires the operation of high-gradient, normal-conducting RF structures in the presence of strong magnetic fields. We have measured the breakdown rate in several RF cavities operating at several frequencies. Cavities operating within solenoidal magnetic fields B > 0.25 T show an increased RF breakdown rate at lower gradients compared with similar operation when B = 0 T. Ultimately, this breakdown behavior limits the maximum safe operating gradient of the cavity. Beyond ionization cooling, this issue affects the design of photoinjectors and klystrons, among other applications. We have built an 805 MHz pillbox-type RF cavity to serve as an experimental testbed for this phenomenon. This cavity is designed to study the problem of RF breakdown in strong magnetic fields using various cavity materials and surface treatments, and with precise control over sources of systematic error. We present results from tests in which the cavity was run with all copper surfaces in a variety of magnetic fields.

Slides MOAD2 [10.792 MB]

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MOPWI020

Development of Simple Tracking Libraries for ALS-U

lattice, simulation, framework, dynamic-aperture

1192

H. Nishimura, D. Robin, K. Song, C. Steier, C. Sun, W. Wan
LBNL, Berkeley, California, USA

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The conceptual lattice design study of a new diffraction-limited light source has become much more computer intensive than that for the 3rd-generation rings. We are in a process of upgrading our existing accelerator modeling and simulation libraries, Goemon* in C++ and a new version Tracy#**, to fulfil such new demand. The C++ version has been actively used on the ALS HPC cluster for multi-objective optimization (MOGA) to optimize the ALS lattice***, and recently for ALS-U****. This time, based on the current version in C#, we extracted its subset and ported it to C and C++. The routines are made thread-safe to enable OpenMP locally, and CPU-time profiling was extensively used to remove redundancies. The new refitting method of quad settings brought smooth switching from 5-dim to 6-dim. The data structure itself is simplified for the use on GPU that is based on our previous effort of tracking particles in GPU*****. Tracy# itself is also upgraded to cooperate with these C/C++ versions. Their use from Python will be also mentioned.
* H. Nishimura, PAC01, 3066-3068.
** H. Nishimura, ICAP09.
*** C. Sun, et. al.,PAC11, 793-795.
**** H. Tarawneh, et. al.,J.Phys.493 012020, 2014.
***** H. Nishimura, et. al.,PAC11, 1764-1766.

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MOPWI027

Open XAL Control Room Experience

controls, software, optics, operation

1214

C.P. Chu, D.G. Maxwell, Y. Zhang
FRIB, East Lansing, Michigan, USA
C.K. Allen, T.A. Pelaia II, A.P. Shishlo
ORNL, Oak Ridge, Tennessee, USA

Funding: This material is based upon work supported by the U.S. Department of Energy under Cooperative Agreement DE-SC0000661 and DE-AC05-00OR22725, the State of Michigan and Michigan State University.
This paper reports the control room experience, lessons learned, and quick deployment approach for the Open XAL application environment. Open XAL is a java-based framework for building high-level accelerator applications, it is a major revision of the XAL framework which was developed at the Spallation Neutron Source (SNS). Open XAL is site neutral and may be deployed at multiple accelerator facilities. Currently, Open XAL is installed at SNS and at the Re-Accelerator facility of Michigan State University. At SNS we are in the final process of replacing the old XAL environment with Open XAL; we describe the upgrade process and our accelerator operations experience using Open XAL. At Michigan State, Open XAL has been tested during a cryomodule commissioning and result will be shown.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPWI027

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WEPMA007

Experimental Study of Multipactor Suppression in Dielectric Materials

multipactoring, electron, vacuum, target

2753

M. El Khaldi, W. Kaabi
LAL, Orsay, France

A novel coaxial resonator to investigate two-surface multipactor discharges on metal and dielectric surfaces in the gap region under vacuum conditions (~10^-8 mbar) has been designed and tested. The resonator is ~ 100 mm in length with an outer diameter of ~ 60 mm (internal dimensions). A pulsed RF source delivers up to 30 W average power over a wide frequency range 650-900 MHz to the RF resonator. The incident and reflected RF signals are monitored by calibrated RF diodes. An electron probe provides temporal measurements of the multipacting electron current with respect to the RF pulses. In this paper we compare and contrast the results from the RF power tests of the alumina (97.6% Al2O3) and quartz samples without a coating, “the non-coated samples” and the Alumina and quartz samples with a thick TiN coating in order to evaluate a home made sputtered titanium nitride (TiN) thin layers as a Multipactor suppressor. The effectiveness of this method is presented and discussed in the paper.

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WEPHA020

Titanium Coating of Ceramics for Accelerator Applications

vacuum, cathode, electron, target

3148

W. Vollenberg, P. Costa Pinto, B. Holliger, A. Sapountzis, M. Taborelli
CERN, Geneva, Switzerland

Titanium thin films can be deposited on ceramics, in particular alumina, without adherence problems. Even after air exposure their secondary electron yield is low compared to alumina and can be further reduced by conditioning or beam scrubbing. In addition, depending on the film thickness, titanium provides different surface resistances that fulfil requirements of ceramics in particle accelerators. Titanium thin films (MOhm square range) are used to suppress electron multipacting and evacuate charges from ceramic surfaces. Thicker films (5-25 Ω square range) are applied to lower the surface resistance so that the beam impedance is reduced. In this contribution, we present the results of a development aimed at coating 2-meter long alumina vacuum chambers with a uniform surface resistivity by a dedicated DC magnetron sputtering configuration.

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WEPTY015

Examination of Beryllium under Intense High Energy Proton Beam at CERN's HiRadMat Facility

experiment, target, proton, instrumentation

3289

K. Ammigan, B.D. Hartsell, P. Hurh, R.M. Zwaska
Fermilab, Batavia, Illinois, USA
A.R. Atherton
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
M. Butcher, M. Calviani, M. Guinchard, R. Losito
CERN, Geneva, Switzerland
O. Caretta, T.R. Davenne, C.J. Densham, M.D. Fitton, P. Loveridge, J. O'Dell
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
V.I. Kuksenko, S.G. Roberts
University of Oxford, Oxford, United Kingdom

Funding: Work supported by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Beryllium is extensively used in various accelerator beam lines and target facilities as material for beam windows, and to a lesser extent, as secondary particle production targets. With increasing beam intensities of future accelerator facilities, it is critical to understand the response of beryllium under extreme conditions to avoid compromising particle production efficiency by limiting beam parameters. As a result, the planned experiment at CERN’s HiRadMat facility will take advantage of the test facility’s tunable high intensity proton beam to probe and investigate the damage mechanisms of several grades of beryllium. The test matrix will consist of multiple arrays of thin discs of varying thicknesses as well as cylinders, each exposed to increasing beam intensities. Online instrumentations will acquire real time temperature, strain, and vibration data of the cylinders, while Post-Irradiation-Examination (PIE) of the discs will exploit advanced microstructural characterization and imaging techniques to analyze grain structures, crack morphology and surface evolution. Details on the experimental design, online measurements and planned PIE efforts are described in this paper.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY015

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WEPTY046

Progress on the MICE 201 MHz Cavities at LBNL

cavity, coupling, simulation, network

3378

T.H. Luo, A.J. DeMello, A.R. Lambert, D. Li, S. Prestemon, S.P. Virostek
LBNL, Berkeley, California, USA

The international Muon Ionization Cooling Experiment aims to demonstrate the transverse cooling of amuon beam by ionization in energy absorbers. The final MICE cooling channel configuration has two RF modules, each housing a 201 MHz RF cavity used to compensate the longitudinal energy loss in the absorbers. The LBNL team has designed and fabricated all MICE RF cavities. The cavities will be post-processed and RF measured before being installed in the RF modules. We present the recent progress on this work, including the low level RF measurement on cavity body and Be windows, the electro-polishing (EP) on the cavity surface, the numerical simulation on cavity Be window detuning, and the ongoing mechanical designing work of cavity components.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY046

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WEPTY047

Thermal and Lorentz Force Analysis of Beryllium Windows for the Rectilinear Muon Cooling Channel

cavity, simulation, collider, emittance

3381

T.H. Luo, D. Li, S.P. Virostek
LBNL, Berkeley, California, USA
D.L. Bowring
Fermilab, Batavia, Illinois, USA
R.B. Palmer, D. Stratakis
BNL, Upton, Long Island, New York, USA

Reduction of the 6-dimensional phase-space of a muon beam by several orders of magnitude is a key requirement for a Muon Collider. Recently, a 12-stage rectilinear ionization cooling channel has been proposed to achieve that goal. The channel consists of a series of low frequency (325 MHz-650 MHz) normal conducting pillbox cavities, which are enclosed within thin beryllium windows (foils) to increase shunt impedance and give a higher field on-axis for a given amount of power. These windows are subject to ohmic heating from RF currents and Lorentz force from the EM field in the cavity, both of which will produce out of plane displacements that can detune the cavity frequency. In this study, using the TEM3P code, we report on a detailed thermal and mechanical analysis for the actual Be windows used on a 325 MHz cavity in a vacuum ionization cooling rectilinear channel for a Muon Collider.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY047

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WEPTY054

Grid Window Tests on an 805-MHz Pillbox Cavity

cavity, scattering, radiation, controls

3393

Y. Torun
Illinois Institute of Technology, Chicago, Illlinois, USA
A. Moretti
Fermilab, Batavia, Illinois, USA

Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program.
Muon ionization cooling channel designs use pillbox shaped RF cavities for improved power efficiency and fine control over phasing of individual cavities. For minimum scattering of the muon beam, the ends should be made out of a small thickness of high radiation length material. Good electrical and thermal conductivity are required to reduce power dissipation and remove the heat efficiently. Thin curved beryllium windows with TiN coating have been used successfully in the past. We have built an alternative window set consisting of grids of tubes and tested these on a pillbox cavity previously used with both thin Be and thick Cu windows. The cavity was operated with a pair of grids as well as a single grid against a flat endplate.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY054

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WEPTY055

Installation and Commissioning of the MICE RF Module Prototype

cavity, vacuum, operation, coupling

3395

Y. Torun, P.G. Lane
Illinois Institute of Technology, Chicago, Illlinois, USA
T.G. Anderson, D.L. Bowring, M. Chung, J.H. Gaynier, M.A. Leonova, A. Moretti, R.J. Pasquinelli, D.W. Peterson, R.P. Schultz
Fermilab, Batavia, Illinois, USA
A.J. DeMello, D. Li, S.P. Virostek
LBNL, Berkeley, California, USA
L. Somaschini
INFN-Pisa, Pisa, Italy

Funding: Supported by the US Department of Energy Office of Science through the Muon Accelerator Program.
A special vacuum vessel prototype was built to house the first production 201 MHz RF cavity for the International Muon Ionization Cooling Experiment (MICE). The resulting prototype RF module has been assembled, instrumented, installed and commissioned at Fermilab's MuCool Test Area and the effort has provided valuable experience for the design of modules that will be used in the cooling channel for the experiment.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY055

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THPF077

Proposal for a 72.75 MHz RFQ for the LINCE Accelerator Complex

rfq, cavity, simulation, pick-up

3861

A.K. Orduz, A. Berjillos, C. Bonțoiu, J.A. Dueñas, I. Martel
University of Huelva, Huelva, Spain
A. Garbayo
AVS, Elgoibar, Spain

Funding: Work partially supported by the Spanish Government (MINECO-CDTI) under program FEDER INTERCONNECTA
The low-energy part of the LINCE facility can be based on a 72.75MHz normal-conducting RFQ designed to give a 450 keV/u boost for A/Q=7 ions in about 5m length. The vanes have been electromagnetically designed to accommodate dedicated RF windows producing effective separation of the RFQ modes in an octagonal-shaped resonance chamber. This article outlines the optimization of the quality factor of the cavity by using numerical methods for electromagnetic calculations. Experimental results of RF test carried out on a prototype are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF077

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