IPAC2015 - List of Authors (Wu, Q.)

Paper	Title	Page
MOBD2	Design and Prototyping of HL-LHC Double Quarter Wave Crab Cavities for SPS Test	64
	S. Verdú-Andrés, S.A. Belomestnykh, I. Ben-Zvi, J. Skaritka, Q. Wu, B. P. Xiao BNL, Upton, Long Island, New York, USA L. Alberty, K. Artoos, R. Calaga, O. Capatina, T. Capelli, F. Carra, N. Kuder, R. Leuxe, C. Zanoni CERN, Geneva, Switzerland S.A. Belomestnykh, I. Ben-Zvi Stony Brook University, Stony Brook, USA Z. Li SLAC, Menlo Park, California, USA A. Ratti LBNL, Berkeley, California, USA
	Funding: Work supported by US DOE via US LARP program, through BSA LLC contract No.DE-AC02-98CH10886 and by EU FP7 HiLumi LHC grant No.284404. Used NERSC resources by US DOE contract No.DE-AC02-05CH11231. The LHC high luminosity project envisages the use of the crabbing technique for increasing and levelling the LHC luminosity. Double-Quarter Wave (DQW) resonators are compact cavities especially designed to meet the technical and performance requirements for LHC beam crabbing. A couple of DQW crab cavities are under preparation and will be tested with beam in the Super Proton Synchrotron (SPS) of CERN by 2017. This paper describes the design and prototyping of DQW crab cavities for the SPS test.
	Slides MOBD2 [6.909 MB]
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TUPMA048	Experimental and Simulational Result of Multipactors in 112 MHz QWR Injector	1938
	T. Xin Stony Brook University, Stony Brook, USA S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, V. Litvinenko, I. Pinayev, J. Skaritka, Q. Wu, B. P. Xiao BNL, Upton, Long Island, New York, USA
	Funding: This work was carried out at Brookhaven Science Associates, LLC under Contracts No. DE-AC02-98CH10886 and at Stony Brook University under grant DE-SC0005713 with the U.S. DOE. The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were install and tested for the first time. During this experiment, we observed several multipacting barriers at varied gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.7 MV gun voltage under pulsed mode after several round of conditioning processes.
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WEPWI015	BNL 56 MHz HOM Damper Prototype Fabrication at JLab	3521
	N.A. Huque, W.A. Clemens, E. Daly JLab, Newport News, Virginia, USA S. Bellavia, G.T. McIntyre, S.K. Seberg, Q. Wu BNL, Upton, Long Island, New York, USA
	A prototype Higher-Order Mode (HOM) Damper was fabricated at JLab for the Relativistic Heavy-Ion Collider’s (RHIC) 56 MHz cavity at Brookhaven National Laboratory (BNL). Primarily constructed from high RRR Niobium and Sapphire, the coaxial damper presented significant challenges in electron-beam welding (EBW), brazing and machining via acid etching. The results of the prototype operation brought about changes in the damper design, due to overheating braze alloys and possible multi-pacting. Five production HOM dampers are currently being fabricated at JLab. This paper outlines the challenges faced in the fabrication process, and the solutions put in place.
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WEPWI049	Commissioning of the 112 MHz SRF Gun and 500 MHz Bunching Cavities for the CeC PoP Linac	3597
	S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, V. Litvinenko, G. Narayan, P. Orfin, I. Pinayev, T. Rao, J. Skaritka, K.S. Smith, R. Than, J.E. Tuozzolo, E. Wang, Q. Wu, B. P. Xiao, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, I. Ben-Zvi, V. Litvinenko, T. Xin Stony Brook University, Stony Brook, USA P.A. McIntosh, A.J. Moss, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. The Coherent electron Cooling Proof-of-Principle (CeC PoP) experiment at BNL includes a short electron linac. During Phase I a 112 MHz superconducting RF photoemission gun and two 500 MHz normal conducting bunching cavities were installed and commissioned. The paper describes the Phase I linac layout and presents commissioning results for the cavities and associated RF, cryogenic and other sub-systems.
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WEPWI050	SRF and RF Systems for LEReC Linac	3600
	S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, A.V. Fedotov, G.T. McIntyre, S. Polizzo, K.S. Smith, R. Than, J.E. Tuozzolo, Q. Wu, B. P. Xiao, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, I. Ben-Zvi Stony Brook University, Stony Brook, USA V. Veshcherevich Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. The Low Energy RHIC electron Cooling (LEReC) is under development at BNL to improve RHIC luminosity at low energies. It will consist of a short electron linac and two cooling sections, one for blue and one for yellow beams. For the first stage of the project, LEReC-1, we will to install a 704 MHz superconducting RF cavity and two normal conducting cavities operating at 704 MHz and 2.1 GHz. The SRF cavity will boost the electron beam energy up to 2 MeV. The warm cavities will be used to correct the energy spread introduced in the SRF cavity. The paper describes layouts of the SRF and RF systems, their parameters and status.
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WEPWI059	Higher Order Mode Filter Design for Double Quarter Wave Crab Cavity for the LHC High Luminosity Upgrade	3627
	B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, J. Skaritka, S. Verdú-Andrés, Q. Wu BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, I. Ben-Zvi Stony Brook University, Stony Brook, USA G. Burt, B.D.S. Hall Cockcroft Institute, Lancaster University, Lancaster, United Kingdom G. Burt Lancaster University, Lancaster, United Kingdom R. Calaga, O. Capatina CERN, Geneva, Switzerland T.J. Jones STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: Work partly supported by US LARP, by US DOE under contract No. DE-AC02-05CH11231 and through BSA under contract No. DE-AC02-98CH10886. Research supported by EU FP7 HiLumi LHC - Grant Agreement 284404. A double quarter wave crab cavity (DQWCC) was designed for the Large Hadron Collider (LHC) luminosity upgrade. A compact Higher Order Mode (HOM) filter with wide stop band at the deflecting mode is developed for this cavity. Multi-physics finite element simulation results are presented. The integration of this design to the cavity cryomodule is described.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI059
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WEPWI060	Cryogenic Test of Double Quarter Wave Crab Cavity for the LHC High Luminosity Upgrade	3630
	B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, C. Cullen, L.R. Hammons, C. Marques, J. Skaritka, S. Verdú-Andrés, Q. Wu BNL, Upton, Long Island, New York, USA L. Alberty, R. Calaga, O. Capatina CERN, Geneva, Switzerland S.A. Belomestnykh, I. Ben-Zvi Stony Brook University, Stony Brook, USA Z. Li SLAC, Menlo Park, California, USA
	Funding: Work partly supported by US LARP, by US DOE under contract No. DE-AC02-05CH11231 and through BSA under contract No. DE-AC02-98CH10886. Research supported by EU FP7 HiLumi LHC - Grant Agreement 284404. A Proof-of-Principle (PoP) Double Quarter Wave Crab Cavity (DQWCC) was designed and fabricated for the Large Hadron Collider (LHC) luminosity upgrade. A vertical cryogenic test has been done at Brookhaven National Lab (BNL). The cavity achieved 4.5 MV deflecting voltage with a quality factor above 3×10⁹. We report the test results of this design.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI060
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WEPWI061	Design of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac	3634
	B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, A.V. Fedotov, G.T. McIntyre, K.S. Smith, J.E. Tuozzolo, Q. Wu, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, I. Ben-Zvi Stony Brook University, Stony Brook, USA V. Veshcherevich Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE. To improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon, the Low Energey RHIC electron Cooler (LEReC) is currently under development at BNL. Two normal conducting cavities, a single cell 704 MHz cavity and a 3 cell 2.1 GHz third harmonic cavity, will be used in LEReC for bunch stretching and energy spread correction. In this paper we report the design of these two cavities.
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THXB2	Crab Cavities: Past, Present, and Future of a Challenging Device	3643
	Q. Wu BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with LARP and the U.S. Department of Energy and EU FP7 HiLumi LHC - Grant Agreement 284404 In two-ring facilities operating with a crossing angle collision scheme, the luminosity can be limited due to incomplete overlap of the colliding bunches. Crab cavities are introduced to restore head-on collisions by providing destined opposite deflection to the head and tail of the bunch. Luminosity increase has been demonstrated at KEKB with global crab crossing, and the Large Hardron Collider (LHC) at CERN is currently designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. This paper reviews the challenges in the technology and implementation of crab cavities, discusses experience in past colliders, ongoing R&D and proposed implementations for future facilities such as HL-LHC, CLIC, ILC, and eRHIC/MEIC.
	Slides THXB2 [4.307 MB]
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THPF033	The First Operation of 56 MHz SRF Cavity in RHIC	3767
	Q. Wu, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, L. DeSanto, D. Goldberg, M. Harvey, T. Hayes, G.T. McIntyre, K. Mernick, P. Orfin, S.K. Seberg, F. Severino, K.S. Smith, R. Than, A. Zaltsman BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. A 56 MHz superconducting RF cavity has been designed, fabricated and installed in the Relativistic Heavy Ion Collider (RHIC). The cavity operated at 4.4 K with a “quiet helium source” to isolate the cavity from environmental acoustic noise. The cavity is a beam driven quarter wave resonator. It is detuned and damped during injection and acceleration cycles and is brought to operation only at store energy. For a first test operation, the cavity voltage was stabilized at 300 kV with full beam current. Within both Au + Au and asymmetrical Au + He3 collisions, luminosity improvement was detected from direct measurement, and the hourglass effect was reduced. One higher order mode (HOM) coupler was installed on the cavity. We report in this paper on our measurement of a broadband HOM spectrum excited by the Au beam.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF033
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Paper

Title

Page

Design and Prototyping of HL-LHC Double Quarter Wave Crab Cavities for SPS Test

64

S. Verdú-Andrés, S.A. Belomestnykh, I. Ben-Zvi, J. Skaritka, Q. Wu, B. P. Xiao
BNL, Upton, Long Island, New York, USA
L. Alberty, K. Artoos, R. Calaga, O. Capatina, T. Capelli, F. Carra, N. Kuder, R. Leuxe, C. Zanoni
CERN, Geneva, Switzerland
S.A. Belomestnykh, I. Ben-Zvi
Stony Brook University, Stony Brook, USA
Z. Li
SLAC, Menlo Park, California, USA
A. Ratti
LBNL, Berkeley, California, USA

Funding: Work supported by US DOE via US LARP program, through BSA LLC contract No.DE-AC02-98CH10886 and by EU FP7 HiLumi LHC grant No.284404. Used NERSC resources by US DOE contract No.DE-AC02-05CH11231.
The LHC high luminosity project envisages the use of the crabbing technique for increasing and levelling the LHC luminosity. Double-Quarter Wave (DQW) resonators are compact cavities especially designed to meet the technical and performance requirements for LHC beam crabbing. A couple of DQW crab cavities are under preparation and will be tested with beam in the Super Proton Synchrotron (SPS) of CERN by 2017. This paper describes the design and prototyping of DQW crab cavities for the SPS test.

Slides MOBD2 [6.909 MB]

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TUPMA048

Experimental and Simulational Result of Multipactors in 112 MHz QWR Injector

1938

T. Xin
Stony Brook University, Stony Brook, USA
S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, V. Litvinenko, I. Pinayev, J. Skaritka, Q. Wu, B. P. Xiao
BNL, Upton, Long Island, New York, USA

Funding: This work was carried out at Brookhaven Science Associates, LLC under Contracts No. DE-AC02-98CH10886 and at Stony Brook University under grant DE-SC0005713 with the U.S. DOE.
The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were install and tested for the first time. During this experiment, we observed several multipacting barriers at varied gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.7 MV gun voltage under pulsed mode after several round of conditioning processes.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-TUPMA048

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WEPWI015

BNL 56 MHz HOM Damper Prototype Fabrication at JLab

3521

N.A. Huque, W.A. Clemens, E. Daly
JLab, Newport News, Virginia, USA
S. Bellavia, G.T. McIntyre, S.K. Seberg, Q. Wu
BNL, Upton, Long Island, New York, USA

A prototype Higher-Order Mode (HOM) Damper was fabricated at JLab for the Relativistic Heavy-Ion Collider’s (RHIC) 56 MHz cavity at Brookhaven National Laboratory (BNL). Primarily constructed from high RRR Niobium and Sapphire, the coaxial damper presented significant challenges in electron-beam welding (EBW), brazing and machining via acid etching. The results of the prototype operation brought about changes in the damper design, due to overheating braze alloys and possible multi-pacting. Five production HOM dampers are currently being fabricated at JLab. This paper outlines the challenges faced in the fabrication process, and the solutions put in place.

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WEPWI049

Commissioning of the 112 MHz SRF Gun and 500 MHz Bunching Cavities for the CeC PoP Linac

3597

S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, V. Litvinenko, G. Narayan, P. Orfin, I. Pinayev, T. Rao, J. Skaritka, K.S. Smith, R. Than, J.E. Tuozzolo, E. Wang, Q. Wu, B. P. Xiao, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, I. Ben-Zvi, V. Litvinenko, T. Xin
Stony Brook University, Stony Brook, USA
P.A. McIntosh, A.J. Moss, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
The Coherent electron Cooling Proof-of-Principle (CeC PoP) experiment at BNL includes a short electron linac. During Phase I a 112 MHz superconducting RF photoemission gun and two 500 MHz normal conducting bunching cavities were installed and commissioned. The paper describes the Phase I linac layout and presents commissioning results for the cavities and associated RF, cryogenic and other sub-systems.

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WEPWI050

SRF and RF Systems for LEReC Linac

3600

S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, A.V. Fedotov, G.T. McIntyre, S. Polizzo, K.S. Smith, R. Than, J.E. Tuozzolo, Q. Wu, B. P. Xiao, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, I. Ben-Zvi
Stony Brook University, Stony Brook, USA
V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
The Low Energy RHIC electron Cooling (LEReC) is under development at BNL to improve RHIC luminosity at low energies. It will consist of a short electron linac and two cooling sections, one for blue and one for yellow beams. For the first stage of the project, LEReC-1, we will to install a 704 MHz superconducting RF cavity and two normal conducting cavities operating at 704 MHz and 2.1 GHz. The SRF cavity will boost the electron beam energy up to 2 MeV. The warm cavities will be used to correct the energy spread introduced in the SRF cavity. The paper describes layouts of the SRF and RF systems, their parameters and status.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI050

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WEPWI059

Higher Order Mode Filter Design for Double Quarter Wave Crab Cavity for the LHC High Luminosity Upgrade

3627

B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, J. Skaritka, S. Verdú-Andrés, Q. Wu
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, I. Ben-Zvi
Stony Brook University, Stony Brook, USA
G. Burt, B.D.S. Hall
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
G. Burt
Lancaster University, Lancaster, United Kingdom
R. Calaga, O. Capatina
CERN, Geneva, Switzerland
T.J. Jones
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

Funding: Work partly supported by US LARP, by US DOE under contract No. DE-AC02-05CH11231 and through BSA under contract No. DE-AC02-98CH10886. Research supported by EU FP7 HiLumi LHC - Grant Agreement 284404.
A double quarter wave crab cavity (DQWCC) was designed for the Large Hadron Collider (LHC) luminosity upgrade. A compact Higher Order Mode (HOM) filter with wide stop band at the deflecting mode is developed for this cavity. Multi-physics finite element simulation results are presented. The integration of this design to the cavity cryomodule is described.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI059

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WEPWI060

Cryogenic Test of Double Quarter Wave Crab Cavity for the LHC High Luminosity Upgrade

3630

B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, C. Cullen, L.R. Hammons, C. Marques, J. Skaritka, S. Verdú-Andrés, Q. Wu
BNL, Upton, Long Island, New York, USA
L. Alberty, R. Calaga, O. Capatina
CERN, Geneva, Switzerland
S.A. Belomestnykh, I. Ben-Zvi
Stony Brook University, Stony Brook, USA
Z. Li
SLAC, Menlo Park, California, USA

Funding: Work partly supported by US LARP, by US DOE under contract No. DE-AC02-05CH11231 and through BSA under contract No. DE-AC02-98CH10886. Research supported by EU FP7 HiLumi LHC - Grant Agreement 284404.
A Proof-of-Principle (PoP) Double Quarter Wave Crab Cavity (DQWCC) was designed and fabricated for the Large Hadron Collider (LHC) luminosity upgrade. A vertical cryogenic test has been done at Brookhaven National Lab (BNL). The cavity achieved 4.5 MV deflecting voltage with a quality factor above 3×10⁹. We report the test results of this design.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI060

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WEPWI061

Design of Normal Conducting 704 MHz and 2.1 GHz Cavities for LEReC Linac

3634

B. P. Xiao, S.A. Belomestnykh, I. Ben-Zvi, J.C. Brutus, A.V. Fedotov, G.T. McIntyre, K.S. Smith, J.E. Tuozzolo, Q. Wu, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, I. Ben-Zvi
Stony Brook University, Stony Brook, USA
V. Veshcherevich
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work is supported by Brookhaven Science Associates, LLC under contract No. DE-AC02-98CH10886 with the US DOE.
To improve RHIC luminosity for heavy ion beam energies below 10 GeV/nucleon, the Low Energey RHIC electron Cooler (LEReC) is currently under development at BNL. Two normal conducting cavities, a single cell 704 MHz cavity and a 3 cell 2.1 GHz third harmonic cavity, will be used in LEReC for bunch stretching and energy spread correction. In this paper we report the design of these two cavities.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPWI061

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THXB2

Crab Cavities: Past, Present, and Future of a Challenging Device

3643

Q. Wu
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with LARP and the U.S. Department of Energy and EU FP7 HiLumi LHC - Grant Agreement 284404
In two-ring facilities operating with a crossing angle collision scheme, the luminosity can be limited due to incomplete overlap of the colliding bunches. Crab cavities are introduced to restore head-on collisions by providing destined opposite deflection to the head and tail of the bunch. Luminosity increase has been demonstrated at KEKB with global crab crossing, and the Large Hardron Collider (LHC) at CERN is currently designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. This paper reviews the challenges in the technology and implementation of crab cavities, discusses experience in past colliders, ongoing R&D and proposed implementations for future facilities such as HL-LHC, CLIC, ILC, and eRHIC/MEIC.

Slides THXB2 [4.307 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THXB2

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THPF033

The First Operation of 56 MHz SRF Cavity in RHIC

3767

Q. Wu, S.A. Belomestnykh, I. Ben-Zvi, M. Blaskiewicz, L. DeSanto, D. Goldberg, M. Harvey, T. Hayes, G.T. McIntyre, K. Mernick, P. Orfin, S.K. Seberg, F. Severino, K.S. Smith, R. Than, A. Zaltsman
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
A 56 MHz superconducting RF cavity has been designed, fabricated and installed in the Relativistic Heavy Ion Collider (RHIC). The cavity operated at 4.4 K with a “quiet helium source” to isolate the cavity from environmental acoustic noise. The cavity is a beam driven quarter wave resonator. It is detuned and damped during injection and acceleration cycles and is brought to operation only at store energy. For a first test operation, the cavity voltage was stabilized at 300 kV with full beam current. Within both Au + Au and asymmetrical Au + He3 collisions, luminosity improvement was detected from direct measurement, and the hourglass effect was reduced. One higher order mode (HOM) coupler was installed on the cavity. We report in this paper on our measurement of a broadband HOM spectrum excited by the Au beam.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF033

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