FEL2013 - List of Authors (Benson, S.V.)

Paper

Title

Page

Study of CSR Effects in the Jefferson Laboratory FEL Driver

58

C.C. Hall, S. Biedron, T.A. Burleson, S.V. Milton, A.L. Morin
CSU, Fort Collins, Colorado, USA
S.V. Benson, D. Douglas, P.E. Evtushenko, F.E. Hannon, R. Li, C. Tennant, S. Zhang
JLAB, Newport News, Virginia, USA
B.E. Carlsten, J.W. Lewellen
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by the Office of Naval Research and the High Energy Laser Joint Technology. Jefferson Laboratory work also received supported under U.S. DOE Contract No. DE-AC05-06OR23177.
In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

TUPSO12

RF Design Approach for an NGLS Linac

226

A. Ratti, J.M. Byrd, J.N. Corlett, L.R. Doolittle, P. Emma, M. Venturini, R.P. Wells
LBNL, Berkeley, California, USA
C. Adolphsen, C.D. Nantista
SLAC, Menlo Park, California, USA
D. Arenius, S.V. Benson, D. Douglas, A. Hutton, G. Neil, W. Oren, G.P. Williams
JLAB, Newport News, Virginia, USA
C.M. Ginsburg, R.D. Kephart, T.J. Peterson, A.I. Sukhanov
Fermilab, Batavia, USA

Funding: Work supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231
The Next Generation Light Source (NGLS) is a design concept for a multibeamline soft x-ray FEL array powered by a ~2.4 GeV CW superconducting linear accelerator, operating with a 1 MHz bunch repetition rate. This paper describes the concepts for the cavity and cryostat design operating at 1.3 GHZ and based on minimal modifications to the design of ILC cryomodules, This leverages the extensive experience derived from R&D that resulted in the ILC design. Due to the different nature of the two applications, particular attention is given now to high loaded Q operation and microphonics control, as well as high reliability and expected up time. The work describes the design and configuration of the linac, including choice of gradient, possible modes of operation, cavity design and RF power, as well as the consequent requirements for the cryogenic system.

THOCNO02

A Proposed High FLUX Ultrashort Pulse X-ray and Gamma-ray Source at JLAB FEL Facility

S. Zhang, S.V. Benson, D. Douglas
JLAB, Newport News, Virginia, USA

Funding: This project was supported by the Commonwealth of Virginia, and by the U.S. DOE Basic Energy Sciences under contract No. DE-AC05-060R23177.
A unique opportunity exists at Jlab FEL Facility to dramatically expand its present operating wavebands into high flux X-ray and Gamma-ray regimes based on Laser Compton Scattering (LCS) process by using the world’s only operating high average power ultrashort pulse FEL and high current ERL machine in existence. The proposed project takes the advantage of our expertise acquired from the previous R&D on high-power lasers and high current ERL accelerator to design an advanced source with photon energy ranging from 10s of eV (soft X-ray) up to MeV (Gamma-ray) and high photon flux on the level of 10¹⁰~10¹³ photons/second. We will show the feasibility study for achieving the expected parameters under the existing machine conditions, and will investigate the possibility to further extend the photon energy and flux with practical machine upgrades and modifications. With such an addition to JLab FEL facility, its photon capability of the JLab FEL facility would cover the broadest spectrum ever, providing ultrashort optical pulses from Gamma to THz for various users. The potential benefits of source go well beyond the research interests of nuclear physics and accelerator technology.
Notice: Authored by JSA, LLC under U.S. DOE ContractNo. DE-AC05-060R23177. The U.S. Government retains non-exclusive, paid-up, irrevocable, world-wide license to publish/reproduce this manuscript.

Paper	Title	Page
MOPSO27	Study of CSR Effects in the Jefferson Laboratory FEL Driver	58
	C.C. Hall, S. Biedron, T.A. Burleson, S.V. Milton, A.L. Morin CSU, Fort Collins, Colorado, USA S.V. Benson, D. Douglas, P.E. Evtushenko, F.E. Hannon, R. Li, C. Tennant, S. Zhang JLAB, Newport News, Virginia, USA B.E. Carlsten, J.W. Lewellen LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by the Office of Naval Research and the High Energy Laser Joint Technology. Jefferson Laboratory work also received supported under U.S. DOE Contract No. DE-AC05-06OR23177. In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

TUPSO12	RF Design Approach for an NGLS Linac	226
	A. Ratti, J.M. Byrd, J.N. Corlett, L.R. Doolittle, P. Emma, M. Venturini, R.P. Wells LBNL, Berkeley, California, USA C. Adolphsen, C.D. Nantista SLAC, Menlo Park, California, USA D. Arenius, S.V. Benson, D. Douglas, A. Hutton, G. Neil, W. Oren, G.P. Williams JLAB, Newport News, Virginia, USA C.M. Ginsburg, R.D. Kephart, T.J. Peterson, A.I. Sukhanov Fermilab, Batavia, USA
	Funding: Work supported by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 The Next Generation Light Source (NGLS) is a design concept for a multibeamline soft x-ray FEL array powered by a ~2.4 GeV CW superconducting linear accelerator, operating with a 1 MHz bunch repetition rate. This paper describes the concepts for the cavity and cryostat design operating at 1.3 GHZ and based on minimal modifications to the design of ILC cryomodules, This leverages the extensive experience derived from R&D that resulted in the ILC design. Due to the different nature of the two applications, particular attention is given now to high loaded Q operation and microphonics control, as well as high reliability and expected up time. The work describes the design and configuration of the linac, including choice of gradient, possible modes of operation, cavity design and RF power, as well as the consequent requirements for the cryogenic system.

THOCNO02	A Proposed High FLUX Ultrashort Pulse X-ray and Gamma-ray Source at JLAB FEL Facility
	S. Zhang, S.V. Benson, D. Douglas JLAB, Newport News, Virginia, USA
	Funding: This project was supported by the Commonwealth of Virginia, and by the U.S. DOE Basic Energy Sciences under contract No. DE-AC05-060R23177. A unique opportunity exists at Jlab FEL Facility to dramatically expand its present operating wavebands into high flux X-ray and Gamma-ray regimes based on Laser Compton Scattering (LCS) process by using the world’s only operating high average power ultrashort pulse FEL and high current ERL machine in existence. The proposed project takes the advantage of our expertise acquired from the previous R&D on high-power lasers and high current ERL accelerator to design an advanced source with photon energy ranging from 10s of eV (soft X-ray) up to MeV (Gamma-ray) and high photon flux on the level of 10¹⁰~10¹³ photons/second. We will show the feasibility study for achieving the expected parameters under the existing machine conditions, and will investigate the possibility to further extend the photon energy and flux with practical machine upgrades and modifications. With such an addition to JLab FEL facility, its photon capability of the JLab FEL facility would cover the broadest spectrum ever, providing ultrashort optical pulses from Gamma to THz for various users. The potential benefits of source go well beyond the research interests of nuclear physics and accelerator technology. Notice: Authored by JSA, LLC under U.S. DOE ContractNo. DE-AC05-060R23177. The U.S. Government retains non-exclusive, paid-up, irrevocable, world-wide license to publish/reproduce this manuscript.