ERL2015 - List of Authors (Kayran, D.)

Paper

Title

Page

Status and Commissioning Results of the R&D ERL at BNL

10

D. Kayran, Z. Altinbas, D.R. Beavis, S.A. Belomestnykh, I. Ben-Zvi, S. Deonarine, D.M. Gassner, R.C. Gupta, H. Hahn, L.R. Hammons, C. Ho, J.P. Jamilkowski, P. K. Kankiya, N. Laloudakis, R.F. Lambiase, V. Litvinenko, G.J. Mahler, L. Masi, G.T. McIntyre, T.A. Miller, J. Morris, D. Phillips, V. Ptitsyn, T. Rao, T. Seda, B. Sheehy, L. Smart, K.S. Smith, T. Srinivasan-Rao, A.N. Steszyn, R. Than, E. Wang, D. Weiss, H. Xie, W. Xu, A. Zaltsman
BNL, Upton, Long Island, New York, USA
S.A. Belomestnykh, I. Ben-Zvi, L.R. Hammons, D. Kayran, V. Litvinenko, V. Ptitsyn
Stony Brook University, Stony Brook, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
An ampere class 20 MeV superconducting Energy Recovery Linac (ERL) is presently under commissioning at Brookhaven National Laboratory (BNL) for testing of concepts relevant for high-energy coherent electron cooling and electron-ion colliders. The injector subsystems tests and installation were finished in fall 2013. The injector includes: SRF photoelectron gun with 1 MW amplifier, 10W green drive-laser system, multi-alkaline cathode deposition system, cathode transport system, beam instrumentation and control. * The first photo current from ERL SRF gun has been observed in fall 2014 after second attempt. Completion of the ERL returning loop components installation is scheduled for April 2015 following full power ERL commissioning. After ERL commissioning in BLDG912 the ERL will be relocated to RHIC IP2 to be used as low energy RHIC electron cooler.
* D.Kayran et al., First test results from SRF photoinjector for the R&D ERL at BNL, IPAC'14, pp. 748-750

Slides MOPDTH014 [13.777 MB]

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TUICLH1027

Characterization of Multi-alkali Antimonide Cathode at Cryogenic Temperatures and its Performance in SRF Gun

H.M. Xie
PKU, Beijing, People's Republic of China
S.A. Belomestnykh, I. Ben-Zvi, D. Kayran, G.T. McIntyre, B. Sheehy, R. Than, E. Wang, D. Weiss, W. Xu
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.
An alkali antimonide photocathode was tested in BNL 704 MHz SRF gun. The cathode QE and lifetime were measured inside the gun. We also observed a reduction on the QE upon cooling down to cryogenic temperature. In this paper, we propose an analytical model and present a Monte-Carlo simulation code to explain this QE decrease. Both results compared with experiments. Effect of cooling the cathode to cryogenic temperature and Schottky effect on QE will be discussed.

Slides TUICLH1027 [1.815 MB]

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TUIDLH1036

Commissioning Program for the 704 MHz SRF Gun at BNL

W. Xu, S.A. Belomestnykh, I. Ben-Zvi, D. Kayran
BNL, Upton, Long Island, New York, USA

A 704 MHz superconducting RF photoemission electron gun for the R&D ERL project is under commissioning at BNL. It successfully generated the first photoemission beam in November 2014. The BNL SRF gun cavity operates well in CW mode up to 2 MV. However, its performance with inserted cathode stalk suffered due to multipacting in the quarter-wavelength choke-joint. A new multipacting-free cathode stalk was designed and tested. The test results proved that it is a truly “multipacting-free” stalk. With the new cathode, the gun is able to operate in CW mode. The total conditioning time of the new cathode stalk is very short. This paper describes configuration of the SRF gun test and the sub-systems. RF and thermal design of new cathode stalk and its conditioning results are presented. Finally, we report the latest results of the SRF gun commissioning, including the cavity performance, cathode QE measurements, beam current/energy measurements.

Slides TUIDLH1036 [5.226 MB]

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WEIALH2048

Current Measurement and Associated Machine Protection in the ERL at BNL

52

T.A. Miller, D.M. Gassner, J.P. Jamilkowski, D. Kayran, M.G. Minty, J. Morris, B. Sheehy
BNL, Upton, Long Island, New York, USA

The R & D Energy Recovery Linac (ERL) at Brookhaven National Laboratory requires accurate and precise current measurements for logging and for machine protection. In this paper we present the techniques used to derive the beam current from the beam charge measurement taken using an integrating current transformer (ICT). The strategy for ramping up the total beam current is discussed, - including the motivation for developing different operating modes with specific pulse structures, taking into account the constraints on the pulse structure imposed by the operating limits of the ICT during initial accelerator commissioning. The electronics packages used for integration and digitization are presented along with methods of synchronization. Finally, results of measurements during the first beam tests are presented.

Slides WEIALH2048 [21.604 MB]

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WEICLH1058

ERL for Low Energy Electron Cooling at RHIC (LEReC)

67

J. Kewisch, M. Blaskiewicz, A.V. Fedotov, D. Kayran, C. Montag, V.H. Ranjbar
BNL, Upton, Long Island, New York, USA

Funding: Work supported by the U.S. Department of Energy.
The Low-energy RHIC electron Cooler (LEReC) system has been approved to be build at the Brookhaven National Laboratory. The electron cooling system will be able to deliver an electron beam of adequate quality in a wide range of electron beam energies (1.6-5 MeV). While existing electron coolers use a DC electron beam this will be the first application of using a bunched electron beam provided by an ERL, paving the way for future electron coolers at higher energies.

Slides WEICLH1058 [2.909 MB]

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Paper	Title	Page
MOPDTH014	Status and Commissioning Results of the R&D ERL at BNL	10
	D. Kayran, Z. Altinbas, D.R. Beavis, S.A. Belomestnykh, I. Ben-Zvi, S. Deonarine, D.M. Gassner, R.C. Gupta, H. Hahn, L.R. Hammons, C. Ho, J.P. Jamilkowski, P. K. Kankiya, N. Laloudakis, R.F. Lambiase, V. Litvinenko, G.J. Mahler, L. Masi, G.T. McIntyre, T.A. Miller, J. Morris, D. Phillips, V. Ptitsyn, T. Rao, T. Seda, B. Sheehy, L. Smart, K.S. Smith, T. Srinivasan-Rao, A.N. Steszyn, R. Than, E. Wang, D. Weiss, H. Xie, W. Xu, A. Zaltsman BNL, Upton, Long Island, New York, USA S.A. Belomestnykh, I. Ben-Zvi, L.R. Hammons, D. Kayran, V. Litvinenko, V. Ptitsyn Stony Brook University, Stony Brook, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy An ampere class 20 MeV superconducting Energy Recovery Linac (ERL) is presently under commissioning at Brookhaven National Laboratory (BNL) for testing of concepts relevant for high-energy coherent electron cooling and electron-ion colliders. The injector subsystems tests and installation were finished in fall 2013. The injector includes: SRF photoelectron gun with 1 MW amplifier, 10W green drive-laser system, multi-alkaline cathode deposition system, cathode transport system, beam instrumentation and control. * The first photo current from ERL SRF gun has been observed in fall 2014 after second attempt. Completion of the ERL returning loop components installation is scheduled for April 2015 following full power ERL commissioning. After ERL commissioning in BLDG912 the ERL will be relocated to RHIC IP2 to be used as low energy RHIC electron cooler. * D.Kayran et al., First test results from SRF photoinjector for the R&D ERL at BNL, IPAC'14, pp. 748-750
	Slides MOPDTH014 [13.777 MB]
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TUICLH1027	Characterization of Multi-alkali Antimonide Cathode at Cryogenic Temperatures and its Performance in SRF Gun
	H.M. Xie PKU, Beijing, People's Republic of China S.A. Belomestnykh, I. Ben-Zvi, D. Kayran, G.T. McIntyre, B. Sheehy, R. Than, E. Wang, D. Weiss, W. Xu 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. An alkali antimonide photocathode was tested in BNL 704 MHz SRF gun. The cathode QE and lifetime were measured inside the gun. We also observed a reduction on the QE upon cooling down to cryogenic temperature. In this paper, we propose an analytical model and present a Monte-Carlo simulation code to explain this QE decrease. Both results compared with experiments. Effect of cooling the cathode to cryogenic temperature and Schottky effect on QE will be discussed.
	Slides TUICLH1027 [1.815 MB]
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TUIDLH1036	Commissioning Program for the 704 MHz SRF Gun at BNL
	W. Xu, S.A. Belomestnykh, I. Ben-Zvi, D. Kayran BNL, Upton, Long Island, New York, USA
	A 704 MHz superconducting RF photoemission electron gun for the R&D ERL project is under commissioning at BNL. It successfully generated the first photoemission beam in November 2014. The BNL SRF gun cavity operates well in CW mode up to 2 MV. However, its performance with inserted cathode stalk suffered due to multipacting in the quarter-wavelength choke-joint. A new multipacting-free cathode stalk was designed and tested. The test results proved that it is a truly “multipacting-free” stalk. With the new cathode, the gun is able to operate in CW mode. The total conditioning time of the new cathode stalk is very short. This paper describes configuration of the SRF gun test and the sub-systems. RF and thermal design of new cathode stalk and its conditioning results are presented. Finally, we report the latest results of the SRF gun commissioning, including the cavity performance, cathode QE measurements, beam current/energy measurements.
	Slides TUIDLH1036 [5.226 MB]
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WEIALH2048	Current Measurement and Associated Machine Protection in the ERL at BNL	52
	T.A. Miller, D.M. Gassner, J.P. Jamilkowski, D. Kayran, M.G. Minty, J. Morris, B. Sheehy BNL, Upton, Long Island, New York, USA
	The R & D Energy Recovery Linac (ERL) at Brookhaven National Laboratory requires accurate and precise current measurements for logging and for machine protection. In this paper we present the techniques used to derive the beam current from the beam charge measurement taken using an integrating current transformer (ICT). The strategy for ramping up the total beam current is discussed, - including the motivation for developing different operating modes with specific pulse structures, taking into account the constraints on the pulse structure imposed by the operating limits of the ICT during initial accelerator commissioning. The electronics packages used for integration and digitization are presented along with methods of synchronization. Finally, results of measurements during the first beam tests are presented.
	Slides WEIALH2048 [21.604 MB]
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WEICLH1058	ERL for Low Energy Electron Cooling at RHIC (LEReC)	67
	J. Kewisch, M. Blaskiewicz, A.V. Fedotov, D. Kayran, C. Montag, V.H. Ranjbar BNL, Upton, Long Island, New York, USA
	Funding: Work supported by the U.S. Department of Energy. The Low-energy RHIC electron Cooler (LEReC) system has been approved to be build at the Brookhaven National Laboratory. The electron cooling system will be able to deliver an electron beam of adequate quality in a wide range of electron beam energies (1.6-5 MeV). While existing electron coolers use a DC electron beam this will be the first application of using a bunched electron beam provided by an ERL, paving the way for future electron coolers at higher energies.
	Slides WEICLH1058 [2.909 MB]
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)