The ResistiveWall Instability in Multipulse Linear Induction Accelerators
Abstract
The resistivewall instability results from the Lorentz force on the beam due to the beam image charge and current. If the beam pipe is perfectly conducting, the electric force due to the image charge attracts the beam to the pipe wall, and the magnetic force due to the image current repels the beam from the wall. For a relativistic beam, these forces almost cancel, leaving a slight attractive force, which is easily overcome by external magnetic focusing. However, if the beam pipe is not perfectly conducting, the magnetic field due to the image current decays on a magneticdiffusion time scale. If the beam pulse is longer than the magnetic diffusion time, the repulsion of the beam tail will be weaker than the repulsion of the beam head. In the absence of an external focusing force, this causes a headtotail sweep of the beam toward the wall. This instability is usually thought to be a concern only for longpulse relativistic electron beams. However, with the advent of multipulse, high current linear induction accelerators, the possibility of pulsetopulse coupling of this instability should be investigated. Lastly, we have explored pulsetopulse coupling using the linear accelerator model for Dual Axis Radiography for Hydrodynamicmore »
 Authors:
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 1352365
 Report Number(s):
 LAUR1623759
Journal ID: ISSN 00933813
 Grant/Contract Number:
 AC5206NA25396
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 IEEE Transactions on Plasma Science
 Additional Journal Information:
 Journal Volume: 45; Journal Issue: 5; Journal ID: ISSN 00933813
 Publisher:
 IEEE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 43 PARTICLE ACCELERATORS; electron beam instabilities; intense relativistic electron beams; linear induction accelerators (LIAs)
Citation Formats
Ekdahl, Carl. The ResistiveWall Instability in Multipulse Linear Induction Accelerators. United States: N. p., 2017.
Web. doi:10.1109/TPS.2017.2681040.
Ekdahl, Carl. The ResistiveWall Instability in Multipulse Linear Induction Accelerators. United States. doi:10.1109/TPS.2017.2681040.
Ekdahl, Carl. 2017.
"The ResistiveWall Instability in Multipulse Linear Induction Accelerators". United States.
doi:10.1109/TPS.2017.2681040.
@article{osti_1352365,
title = {The ResistiveWall Instability in Multipulse Linear Induction Accelerators},
author = {Ekdahl, Carl},
abstractNote = {The resistivewall instability results from the Lorentz force on the beam due to the beam image charge and current. If the beam pipe is perfectly conducting, the electric force due to the image charge attracts the beam to the pipe wall, and the magnetic force due to the image current repels the beam from the wall. For a relativistic beam, these forces almost cancel, leaving a slight attractive force, which is easily overcome by external magnetic focusing. However, if the beam pipe is not perfectly conducting, the magnetic field due to the image current decays on a magneticdiffusion time scale. If the beam pulse is longer than the magnetic diffusion time, the repulsion of the beam tail will be weaker than the repulsion of the beam head. In the absence of an external focusing force, this causes a headtotail sweep of the beam toward the wall. This instability is usually thought to be a concern only for longpulse relativistic electron beams. However, with the advent of multipulse, high current linear induction accelerators, the possibility of pulsetopulse coupling of this instability should be investigated. Lastly, we have explored pulsetopulse coupling using the linear accelerator model for Dual Axis Radiography for Hydrodynamic Testing beam dynamics code, and we present the results of this paper.},
doi = {10.1109/TPS.2017.2681040},
journal = {IEEE Transactions on Plasma Science},
number = 5,
volume = 45,
place = {United States},
year = 2017,
month = 5
}

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