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Title: Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun

Abstract

Energy degradation due to back-bombardment effect is quite serious to produce high-brightness electron beam with long macro-pulse with thermionic rf gun. To avoid the back-bombardment problem, a laser photo cathode is used at many FEL facilities, but usually it costs high and not easy to operate. Thus we have studied long pulse operation of the rf gun with thermionic cathode, which is inexpensive and easy to operate compared to the photocathode rf gun. In this work, to reduce the energy degradation, we controlled input rf power amplitude by controlling pulse forming network of the power modulator for klystron. We have successfully increased the pulse duration up to 4 {mu}s by increasing the rf power from 7.8 MW to 8.5 MW during the macro pulse.

Authors:
; ; ; ; ; ; ; ; ; ;  [1]
  1. Institute of Advanced Energy, Kyoto University, Gokasyo, Uji, Kyoto 611-0011 (Japan)
Publication Date:
OSTI Identifier:
21049360
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436048; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; BRIGHTNESS; ELECTRON BEAMS; ENERGY LOSSES; FREE ELECTRON LASERS; HIGH-FREQUENCY DISCHARGES; KLYSTRONS; LASER RADIATION; OPERATION; PHOTOCATHODES; PULSES; RF SYSTEMS

Citation Formats

Kii, Toshiteru, Nakai, Yoko, Fukui, Toshio, Zen, Heishun, Kusukame, Kohichi, Okawachi, Norihito, Nakano, Masatsugu, Masuda, Kai, Ohgaki, Hideaki, Yoshikawa, Kiyoshi, and Yamazaki, Tetsuo. Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun. United States: N. p., 2007. Web. doi:10.1063/1.2436048.
Kii, Toshiteru, Nakai, Yoko, Fukui, Toshio, Zen, Heishun, Kusukame, Kohichi, Okawachi, Norihito, Nakano, Masatsugu, Masuda, Kai, Ohgaki, Hideaki, Yoshikawa, Kiyoshi, & Yamazaki, Tetsuo. Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun. United States. doi:10.1063/1.2436048.
Kii, Toshiteru, Nakai, Yoko, Fukui, Toshio, Zen, Heishun, Kusukame, Kohichi, Okawachi, Norihito, Nakano, Masatsugu, Masuda, Kai, Ohgaki, Hideaki, Yoshikawa, Kiyoshi, and Yamazaki, Tetsuo. Fri . "Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun". United States. doi:10.1063/1.2436048.
@article{osti_21049360,
title = {Reducing Energy Degradation Due to Back-bombardment Effect with Modulated RF Input in S-band Thermionic RF Gun},
author = {Kii, Toshiteru and Nakai, Yoko and Fukui, Toshio and Zen, Heishun and Kusukame, Kohichi and Okawachi, Norihito and Nakano, Masatsugu and Masuda, Kai and Ohgaki, Hideaki and Yoshikawa, Kiyoshi and Yamazaki, Tetsuo},
abstractNote = {Energy degradation due to back-bombardment effect is quite serious to produce high-brightness electron beam with long macro-pulse with thermionic rf gun. To avoid the back-bombardment problem, a laser photo cathode is used at many FEL facilities, but usually it costs high and not easy to operate. Thus we have studied long pulse operation of the rf gun with thermionic cathode, which is inexpensive and easy to operate compared to the photocathode rf gun. In this work, to reduce the energy degradation, we controlled input rf power amplitude by controlling pulse forming network of the power modulator for klystron. We have successfully increased the pulse duration up to 4 {mu}s by increasing the rf power from 7.8 MW to 8.5 MW during the macro pulse.},
doi = {10.1063/1.2436048},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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