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Title: Gain and efficiency enhancement of a Cerenkov free electron laser by a prebunched electron beam in a dielectric loaded waveguide

Abstract

A density prebunched electron beam on a Cerenkov free electron laser (CFEL) offers considerable enhancement in gain and efficiency in a dielectric loaded waveguide. The growth rate, efficiency, and gain were evaluated based on experimentally known parameters relevant to the CFEL. It was found that the growth rate, efficiency, and gain of the CFEL increase with the modulation index and has the largest value when the modulation index approaches unity in addition to the frequency and wave number of the prebunched beam are comparable to that of the radiation wave, i.e., when the prebunched beam velocity is comparable to the phase velocity of the radiation wave. The growth rate of the CFEL instability scales as one third power of the beam current. Moreover, the phase velocity of the radiation wave scales as minus one half power of the effective permittivity.

Authors:
;  [1]
  1. Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No. 1, Sector-22, Rohini, Delhi-110085 (India)
Publication Date:
OSTI Identifier:
20976607
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2722310; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; BEAM BUNCHING; BEAM CURRENTS; CHERENKOV RADIATION; DIELECTRIC MATERIALS; EFFICIENCY; ELECTRON BEAMS; FREE ELECTRON LASERS; GAIN; PERMITTIVITY; PHASE VELOCITY; WAVEGUIDES

Citation Formats

Sharma, Suresh C., and Bhasin, Anuradha. Gain and efficiency enhancement of a Cerenkov free electron laser by a prebunched electron beam in a dielectric loaded waveguide. United States: N. p., 2007. Web. doi:10.1063/1.2722310.
Sharma, Suresh C., & Bhasin, Anuradha. Gain and efficiency enhancement of a Cerenkov free electron laser by a prebunched electron beam in a dielectric loaded waveguide. United States. doi:10.1063/1.2722310.
Sharma, Suresh C., and Bhasin, Anuradha. Tue . "Gain and efficiency enhancement of a Cerenkov free electron laser by a prebunched electron beam in a dielectric loaded waveguide". United States. doi:10.1063/1.2722310.
@article{osti_20976607,
title = {Gain and efficiency enhancement of a Cerenkov free electron laser by a prebunched electron beam in a dielectric loaded waveguide},
author = {Sharma, Suresh C. and Bhasin, Anuradha},
abstractNote = {A density prebunched electron beam on a Cerenkov free electron laser (CFEL) offers considerable enhancement in gain and efficiency in a dielectric loaded waveguide. The growth rate, efficiency, and gain were evaluated based on experimentally known parameters relevant to the CFEL. It was found that the growth rate, efficiency, and gain of the CFEL increase with the modulation index and has the largest value when the modulation index approaches unity in addition to the frequency and wave number of the prebunched beam are comparable to that of the radiation wave, i.e., when the prebunched beam velocity is comparable to the phase velocity of the radiation wave. The growth rate of the CFEL instability scales as one third power of the beam current. Moreover, the phase velocity of the radiation wave scales as minus one half power of the effective permittivity.},
doi = {10.1063/1.2722310},
journal = {Physics of Plasmas},
number = 5,
volume = 14,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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