Corkscrew Motion of an Electron Beam due to Coherent Variations in Accelerating Potentials
Abstract
Corkscrew motion results from the interaction of fluctuations of beam electron energy with accidental magnetic dipoles caused by misalignment of the beam transport solenoids. Corkscrew is a serious concern for highcurrent linear induction accelerators (LIA). A simple scaling law for corkscrew amplitude derived from a theory based on a constantenergy beam coasting through a uniform magnetic field has often been used to assess LIA vulnerability to this effect. We use a beam dynamics code to verify that this scaling also holds for an accelerated beam in a nonuniform magnetic field, as in a real accelerator. Results of simulations with this code are strikingly similar to measurements on one of the LIAs at Los Alamos National Laboratory.
 Authors:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 1324545
 Report Number(s):
 LAUR1626989
TRN: US1700056
 DOE Contract Number:
 AC5206NA25396
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 43 PARTICLE ACCELERATORS; INDUCTION; INTERACTIONS; SIMULATION; ELECTRON BEAMS; FLUCTUATIONS; SCALING LAWS; LANL; SOLENOIDS; BEAM DYNAMICS; MAGNETIC DIPOLES; MAGNETIC FIELDS; ACCELERATORS; ELECTRIC POTENTIAL; BEAM BENDING MAGNETS; AMPLITUDES; KILO AMP BEAM CURRENTS; L CODES; linear induction accelerators; electron beam dynamics; electron beam stability
Citation Formats
Ekdahl, Carl August. Corkscrew Motion of an Electron Beam due to Coherent Variations in Accelerating Potentials. United States: N. p., 2016.
Web. doi:10.2172/1324545.
Ekdahl, Carl August. Corkscrew Motion of an Electron Beam due to Coherent Variations in Accelerating Potentials. United States. doi:10.2172/1324545.
Ekdahl, Carl August. 2016.
"Corkscrew Motion of an Electron Beam due to Coherent Variations in Accelerating Potentials". United States.
doi:10.2172/1324545. https://www.osti.gov/servlets/purl/1324545.
@article{osti_1324545,
title = {Corkscrew Motion of an Electron Beam due to Coherent Variations in Accelerating Potentials},
author = {Ekdahl, Carl August},
abstractNote = {Corkscrew motion results from the interaction of fluctuations of beam electron energy with accidental magnetic dipoles caused by misalignment of the beam transport solenoids. Corkscrew is a serious concern for highcurrent linear induction accelerators (LIA). A simple scaling law for corkscrew amplitude derived from a theory based on a constantenergy beam coasting through a uniform magnetic field has often been used to assess LIA vulnerability to this effect. We use a beam dynamics code to verify that this scaling also holds for an accelerated beam in a nonuniform magnetic field, as in a real accelerator. Results of simulations with this code are strikingly similar to measurements on one of the LIAs at Los Alamos National Laboratory.},
doi = {10.2172/1324545},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 9
}

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