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Title: Dark Current Simulation for Linear Collider Accelerator Structures

Abstract

The dynamics of field-emitted electrons in the traveling wave fields of a constant gradient (tapered) disk-loaded waveguide is followed numerically. Previous simulations have been limited to constant impedance (uniform) structures for sake of simplicity since only the fields in a unit cell is needed. Using a finite element field solver on a parallel computer, the fields in the tapered structure can now be readily generated. We will obtain the characteristics of the dark current emitted from both structure types and compare the two results with and without the effect of secondary electrons. The NLC and JLC detuned structures are considered to study if dark current may pose a problem for high gradient acceleration in the next generation of Linear Colliders.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1023265
Report Number(s):
SLAC-REPRINT-2011-010
TRN: US1104408
DOE Contract Number:
AC02-76SF00515
Resource Type:
Conference
Resource Relation:
Conference: 17th IEEE Particle Accelerator Conference (PAC 97): Accelerator Science, Technology and Applications, 12-16 May 1997, Vancouver, British Columbia, Canada
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; ELECTRONS; IMPEDANCE; LINEAR COLLIDERS; SIMULATION; WAVEGUIDES; Accelerators,ACCSYS

Citation Formats

Ng, C.K., Li, Z., Zhan, X., Srinivas, V., Wang, J., Ko, K., and /SLAC. Dark Current Simulation for Linear Collider Accelerator Structures. United States: N. p., 2011. Web.
Ng, C.K., Li, Z., Zhan, X., Srinivas, V., Wang, J., Ko, K., & /SLAC. Dark Current Simulation for Linear Collider Accelerator Structures. United States.
Ng, C.K., Li, Z., Zhan, X., Srinivas, V., Wang, J., Ko, K., and /SLAC. 2011. "Dark Current Simulation for Linear Collider Accelerator Structures". United States. doi:.
@article{osti_1023265,
title = {Dark Current Simulation for Linear Collider Accelerator Structures},
author = {Ng, C.K. and Li, Z. and Zhan, X. and Srinivas, V. and Wang, J. and Ko, K. and /SLAC},
abstractNote = {The dynamics of field-emitted electrons in the traveling wave fields of a constant gradient (tapered) disk-loaded waveguide is followed numerically. Previous simulations have been limited to constant impedance (uniform) structures for sake of simplicity since only the fields in a unit cell is needed. Using a finite element field solver on a parallel computer, the fields in the tapered structure can now be readily generated. We will obtain the characteristics of the dark current emitted from both structure types and compare the two results with and without the effect of secondary electrons. The NLC and JLC detuned structures are considered to study if dark current may pose a problem for high gradient acceleration in the next generation of Linear Colliders.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2011,
month = 8
}

Conference:
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