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Title: Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory

Abstract

Since a comb-type rf shield was proposed in 2003 as a rf shield for future high-intensity accelerators, various types of bellow chambers and gate valves with this rf shield have been installed in the KEK B-Factory rings in series and tested with beams. Through beam tests to check the performance, a structural simplification has been tried in parallel. The temperatures of the bellow corrugations decreased by a factor of 3-6 compared to those with a conventional finger-type rf shield in most cases. The temperatures of the body of the gate valves also decreased by a factor of 2-5. These results demonstrated the availability of the comb-type rf shield. Although a discharge was observed in one simplified model, the latest model has shown no problem up to a stored beam current of 1.8 A (1.3 mA/bunch, 6 mm bunch length). Experiences with the comb-type rf shield in these four-year beam tests are reviewed here.

Authors:
; ; ; ; ; ; ; ; ;  [1];  [2];  [3];  [4]
  1. High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan)
  2. (BINP), Novosibirsk 630090 (Russian Federation)
  3. (Switzerland)
  4. (Japan)
Publication Date:
OSTI Identifier:
20953410
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 4; Other Information: DOI: 10.1063/1.2723747; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BEAM BUNCHING; BEAM CURRENTS; MESON FACTORIES; PARTICLE BEAMS; STORAGE RINGS; VALVES

Citation Formats

Suetsugu, Yusuke, Kanazawa, Ken-ichi, Shibata, Kyo, Shirai, Mitsuru, Bondar, Aleksander E., Kuzminykh, Victor S., Gorbovsky, Aleksander I., Sonderegger, Kurt, Morii, Minoru, Kawada, Kakuyu, Budker Institute of Nuclear Physics, VAT Vakuumventile AG, Haag CH-9469, and VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023. Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory. United States: N. p., 2007. Web. doi:10.1063/1.2723747.
Suetsugu, Yusuke, Kanazawa, Ken-ichi, Shibata, Kyo, Shirai, Mitsuru, Bondar, Aleksander E., Kuzminykh, Victor S., Gorbovsky, Aleksander I., Sonderegger, Kurt, Morii, Minoru, Kawada, Kakuyu, Budker Institute of Nuclear Physics, VAT Vakuumventile AG, Haag CH-9469, & VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023. Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory. United States. doi:10.1063/1.2723747.
Suetsugu, Yusuke, Kanazawa, Ken-ichi, Shibata, Kyo, Shirai, Mitsuru, Bondar, Aleksander E., Kuzminykh, Victor S., Gorbovsky, Aleksander I., Sonderegger, Kurt, Morii, Minoru, Kawada, Kakuyu, Budker Institute of Nuclear Physics, VAT Vakuumventile AG, Haag CH-9469, and VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023. Sun . "Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory". United States. doi:10.1063/1.2723747.
@article{osti_20953410,
title = {Development of bellows and gate valves with a comb-type rf shield for high-current accelerators: Four-year beam test at KEK B-Factory},
author = {Suetsugu, Yusuke and Kanazawa, Ken-ichi and Shibata, Kyo and Shirai, Mitsuru and Bondar, Aleksander E. and Kuzminykh, Victor S. and Gorbovsky, Aleksander I. and Sonderegger, Kurt and Morii, Minoru and Kawada, Kakuyu and Budker Institute of Nuclear Physics and VAT Vakuumventile AG, Haag CH-9469 and VAT SKK Vacuum Ltd., Yokohama, Kanagawa 240-0023},
abstractNote = {Since a comb-type rf shield was proposed in 2003 as a rf shield for future high-intensity accelerators, various types of bellow chambers and gate valves with this rf shield have been installed in the KEK B-Factory rings in series and tested with beams. Through beam tests to check the performance, a structural simplification has been tried in parallel. The temperatures of the bellow corrugations decreased by a factor of 3-6 compared to those with a conventional finger-type rf shield in most cases. The temperatures of the body of the gate valves also decreased by a factor of 2-5. These results demonstrated the availability of the comb-type rf shield. Although a discharge was observed in one simplified model, the latest model has shown no problem up to a stored beam current of 1.8 A (1.3 mA/bunch, 6 mm bunch length). Experiences with the comb-type rf shield in these four-year beam tests are reviewed here.},
doi = {10.1063/1.2723747},
journal = {Review of Scientific Instruments},
number = 4,
volume = 78,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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