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Title: High voltage threshold for stable operation in a dc electron gun

Abstract

We report clear observation of a high voltage (HV) threshold for stable operation in a dc electron gun. The HV hold-off time without any discharge is longer than many hours for operation below the threshold, while it is roughly 10 min above the threshold. The HV threshold corresponds to the minimum voltage where discharge ceases. The threshold increases with the number of discharges during HV conditioning of the gun. Above the threshold, the amount of gas desorption per discharge increases linearly with the voltage difference from the threshold. The present experimental observations can be explained by an avalanche discharge model based on the interplay between electron stimulated desorption (ESD) from the anode surface and subsequent secondary electron emission from the cathode by the impact of ionic components of the ESD molecules or atoms.

Authors:
 [1];  [2]
  1. High Energy Accelerator Research Organization (KEK), Oho, Tsukuba, Ibaraki 305-0801 (Japan)
  2. National Institutes for Quantum and Radiological Science and Technology (QST), Tokai, Naka, Ibaraki 319-1195 (Japan)
Publication Date:
OSTI Identifier:
22590639
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 1; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANODES; ATOMS; CATHODES; DESORPTION; ELECTRIC POTENTIAL; ELECTRON EMISSION; ELECTRON GUNS; MOLECULES; OPERATION; SURFACES

Citation Formats

Yamamoto, Masahiro, E-mail: masahiro@post.kek.jp, and Nishimori, Nobuyuki, E-mail: n-nishim@tagen.tohoku.ac.jp. High voltage threshold for stable operation in a dc electron gun. United States: N. p., 2016. Web. doi:10.1063/1.4955180.
Yamamoto, Masahiro, E-mail: masahiro@post.kek.jp, & Nishimori, Nobuyuki, E-mail: n-nishim@tagen.tohoku.ac.jp. High voltage threshold for stable operation in a dc electron gun. United States. doi:10.1063/1.4955180.
Yamamoto, Masahiro, E-mail: masahiro@post.kek.jp, and Nishimori, Nobuyuki, E-mail: n-nishim@tagen.tohoku.ac.jp. Mon . "High voltage threshold for stable operation in a dc electron gun". United States. doi:10.1063/1.4955180.
@article{osti_22590639,
title = {High voltage threshold for stable operation in a dc electron gun},
author = {Yamamoto, Masahiro, E-mail: masahiro@post.kek.jp and Nishimori, Nobuyuki, E-mail: n-nishim@tagen.tohoku.ac.jp},
abstractNote = {We report clear observation of a high voltage (HV) threshold for stable operation in a dc electron gun. The HV hold-off time without any discharge is longer than many hours for operation below the threshold, while it is roughly 10 min above the threshold. The HV threshold corresponds to the minimum voltage where discharge ceases. The threshold increases with the number of discharges during HV conditioning of the gun. Above the threshold, the amount of gas desorption per discharge increases linearly with the voltage difference from the threshold. The present experimental observations can be explained by an avalanche discharge model based on the interplay between electron stimulated desorption (ESD) from the anode surface and subsequent secondary electron emission from the cathode by the impact of ionic components of the ESD molecules or atoms.},
doi = {10.1063/1.4955180},
journal = {Applied Physics Letters},
number = 1,
volume = 109,
place = {United States},
year = {Mon Jul 04 00:00:00 EDT 2016},
month = {Mon Jul 04 00:00:00 EDT 2016}
}
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