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Title: Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary

Abstract

An important aspect of plasma wake field accelerators (PWFA) is stable propagation of the drive beam. In the under dense plasma regime, the drive beam creates an ion channel which acts on the beam as a strong thick focusing lens. The ion channel causes the beam to undergo multiple betatron oscillations along the length of the plasma. There are several advantages if the beam size can be matched to a constant radius. First, simulations have shown that instabilities such as hosing are reduced when the beam is matched [1]. Second, synchrotron radiation losses are minimized when the beam is matched. Third, an initially matched beam will propagate with no significant change in beam size in spite of large energy loss or gain. Coupling to the plasma with a matched radius can be difficult in some cases. This paper shows how an appropriate density ramp at the plasma entrance can be useful for achieving a matched beam. Additionally, the density ramp is helpful in bringing a misaligned trailing beam onto the drive beam axis. A plasma source with boundary profiles useful for matching has been created for the E-164X PWFA experiments at SLAC.

Authors:
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Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
876443
Report Number(s):
SLAC-PUB-11643
TRN: US200606%%807
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Conference: Prepared for Particle Accelerator Conference (PAC 05), Knoxville, Tennessee, 16-20 May 2005
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATORS; BETATRON OSCILLATIONS; FOCUSING; PLASMA; STANFORD LINEAR ACCELERATOR CENTER; SYNCHROTRON RADIATION; WAKEFIELD ACCELERATORS; Accelerators,ACCPHY, ACCSYS

Citation Formats

Marsh, K.A., Clayton, C.E., Huang, C., Johnson, D.K., Joshi, C., Lu, W., Mori, W.B., Zhou, M., /UCLA, Barnes, C.D., Decker, F.J., Hogan, M.J., Iverson, R.H., Krejcik, P., O'Connell, C.L., Siemann, R., Walz, D.R., /SLAC, Deng, S., Katsouleas, T.C., Muggli, P., Oz, E., and /Southern California U. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary. United States: N. p., 2006. Web.
Marsh, K.A., Clayton, C.E., Huang, C., Johnson, D.K., Joshi, C., Lu, W., Mori, W.B., Zhou, M., /UCLA, Barnes, C.D., Decker, F.J., Hogan, M.J., Iverson, R.H., Krejcik, P., O'Connell, C.L., Siemann, R., Walz, D.R., /SLAC, Deng, S., Katsouleas, T.C., Muggli, P., Oz, E., & /Southern California U. Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary. United States.
Marsh, K.A., Clayton, C.E., Huang, C., Johnson, D.K., Joshi, C., Lu, W., Mori, W.B., Zhou, M., /UCLA, Barnes, C.D., Decker, F.J., Hogan, M.J., Iverson, R.H., Krejcik, P., O'Connell, C.L., Siemann, R., Walz, D.R., /SLAC, Deng, S., Katsouleas, T.C., Muggli, P., Oz, E., and /Southern California U. Fri . "Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary". United States. doi:. https://www.osti.gov/servlets/purl/876443.
@article{osti_876443,
title = {Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary},
author = {Marsh, K.A. and Clayton, C.E. and Huang, C. and Johnson, D.K. and Joshi, C. and Lu, W. and Mori, W.B. and Zhou, M. and /UCLA and Barnes, C.D. and Decker, F.J. and Hogan, M.J. and Iverson, R.H. and Krejcik, P. and O'Connell, C.L. and Siemann, R. and Walz, D.R. and /SLAC and Deng, S. and Katsouleas, T.C. and Muggli, P. and Oz, E. and /Southern California U.},
abstractNote = {An important aspect of plasma wake field accelerators (PWFA) is stable propagation of the drive beam. In the under dense plasma regime, the drive beam creates an ion channel which acts on the beam as a strong thick focusing lens. The ion channel causes the beam to undergo multiple betatron oscillations along the length of the plasma. There are several advantages if the beam size can be matched to a constant radius. First, simulations have shown that instabilities such as hosing are reduced when the beam is matched [1]. Second, synchrotron radiation losses are minimized when the beam is matched. Third, an initially matched beam will propagate with no significant change in beam size in spite of large energy loss or gain. Coupling to the plasma with a matched radius can be difficult in some cases. This paper shows how an appropriate density ramp at the plasma entrance can be useful for achieving a matched beam. Additionally, the density ramp is helpful in bringing a misaligned trailing beam onto the drive beam axis. A plasma source with boundary profiles useful for matching has been created for the E-164X PWFA experiments at SLAC.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Feb 17 00:00:00 EST 2006},
month = {Fri Feb 17 00:00:00 EST 2006}
}

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