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Title: Practical experience in extending the ion source and injection system H{sup -}-ion source duty cycle

Abstract

The ion source and injection system H{sup -} Penning surface-plasma source is currently being developed on the ion source development rig at Rutherford Appleton Laboratory in order to meet the requirements for the next generation of high-power proton drivers. Finite element modeling has been used previously to study the effect of increasing the duty cycle. The main requirement to allow increased duty cycles is improved cooling. By simply reducing the thickness of a sheet of mica to improve thermal conductance to the cooling system, duty cycles of 1.5 ms at 50 Hz can be achieved. Slight increase in hydrogen flow rate is required as the duty cycle is increased. As the duty cycle is increased the output current reduces, however, there is no change in beam emittance. The source cooling system is described and the heat flows within the source are discussed.

Authors:
; ;  [1]
  1. Rutherford Appleton Laboratory, Oxfordshire OX11 0QX (United Kingdom)
Publication Date:
OSTI Identifier:
20779005
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 77; Journal Issue: 3; Conference: 11. international conference on ion sources, Caen (France), 12-16 Sep 2005; Other Information: DOI: 10.1063/1.2166427; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BEAM EMITTANCE; COOLING; FINITE ELEMENT METHOD; FLOW RATE; HEAT FLUX; HYDROGEN; HYDROGEN IONS 1 MINUS; MICA; PARTICLE BEAMS; PENNING ION SOURCES; PLASMA; PROTONS; THICKNESS

Citation Formats

Faircloth, D.C., Whitehead, M.O., and Wood, T.. Practical experience in extending the ion source and injection system H{sup -}-ion source duty cycle. United States: N. p., 2006. Web. doi:10.1063/1.2166427.
Faircloth, D.C., Whitehead, M.O., & Wood, T.. Practical experience in extending the ion source and injection system H{sup -}-ion source duty cycle. United States. doi:10.1063/1.2166427.
Faircloth, D.C., Whitehead, M.O., and Wood, T.. Wed . "Practical experience in extending the ion source and injection system H{sup -}-ion source duty cycle". United States. doi:10.1063/1.2166427.
@article{osti_20779005,
title = {Practical experience in extending the ion source and injection system H{sup -}-ion source duty cycle},
author = {Faircloth, D.C. and Whitehead, M.O. and Wood, T.},
abstractNote = {The ion source and injection system H{sup -} Penning surface-plasma source is currently being developed on the ion source development rig at Rutherford Appleton Laboratory in order to meet the requirements for the next generation of high-power proton drivers. Finite element modeling has been used previously to study the effect of increasing the duty cycle. The main requirement to allow increased duty cycles is improved cooling. By simply reducing the thickness of a sheet of mica to improve thermal conductance to the cooling system, duty cycles of 1.5 ms at 50 Hz can be achieved. Slight increase in hydrogen flow rate is required as the duty cycle is increased. As the duty cycle is increased the output current reduces, however, there is no change in beam emittance. The source cooling system is described and the heat flows within the source are discussed.},
doi = {10.1063/1.2166427},
journal = {Review of Scientific Instruments},
number = 3,
volume = 77,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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