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Title: Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders

Abstract

We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
896726
Report Number(s):
SLAC-PUB-12265
TRN: US0700880
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys.Rev.ST Accel.Beams 9:102001,2006
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; CHARGED PARTICLES; DAMPING; DILUTION; EFFICIENCY; ELECTROMAGNETIC FIELDS; LINEAR COLLIDERS; STANFORD LINEAR ACCELERATOR CENTER; TRAVELLING WAVES; Accelerators,ACCPHY

Citation Formats

Jones, R.M., Adolphsen, C.E., Wang, J.W., Li, Z., and /SLAC. Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders. United States: N. p., 2006. Web. doi:10.1103/PhysRevSTAB.9.102001.
Jones, R.M., Adolphsen, C.E., Wang, J.W., Li, Z., & /SLAC. Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders. United States. doi:10.1103/PhysRevSTAB.9.102001.
Jones, R.M., Adolphsen, C.E., Wang, J.W., Li, Z., and /SLAC. Mon . "Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders". United States. doi:10.1103/PhysRevSTAB.9.102001. https://www.osti.gov/servlets/purl/896726.
@article{osti_896726,
title = {Wakefield Damping in a Pair of X-Band Accelerators for Linear Colliders},
author = {Jones, R.M. and Adolphsen, C.E. and Wang, J.W. and Li, Z. and /SLAC},
abstractNote = {We consider means to damp the wake-field left behind ultra-relativistic charges. In particular, we focus on a pair of travelling wave accelerators operating at an X-band frequency of 11.424 GHz. In order to maximize the efficiency of acceleration, in the context of a linear collider, multiple bunches of charged particles are accelerated within a given pulse of the electromagnetic field. The wake-field left behind successive bunches, if left unchecked, can seriously disturb the progress of trailing bunches and can lead to an appreciable dilution in the emittance of the beam. We report on a method to minimize the influence of the wake-field on trailing bunches. This method entails detuning the characteristic mode frequencies which make-up the electromagnetic field, damping the wake-field, and interleaving the frequencies of adjacent accelerating structures. Theoretical predictions of the wake-field and modes, based on a circuit model, are compared with experimental measurements of the wake-field conducted within the ASSET facility at SLAC. Very good agreement is obtained between theory and experiment and this allows us to have some confidence in designing the damping of wake-fields in a future linear collider consisting of several thousand of these accelerating structures.},
doi = {10.1103/PhysRevSTAB.9.102001},
journal = {Phys.Rev.ST Accel.Beams 9:102001,2006},
number = ,
volume = ,
place = {United States},
year = {Mon Dec 18 00:00:00 EST 2006},
month = {Mon Dec 18 00:00:00 EST 2006}
}
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