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Title: Design and Testing of a High Pressure Gas Target for Fast Neutron Resonance Radiography

Abstract

A high pressure deuterium gas target has been designed to provide high-flux fast neutrons using the D(d,n){sup 3}He reaction for use as a neutron source. The deuterium gas cell holds 4 atm D{sub 2} gas at 298K and is projected to tolerate a beam current of {approx}50 {micro}A of 3.0 MeV deuterons for 8 hours of continuous use. The high-pressure gas cell is designed to provide a fast neutron flux on the order of 10{sup 5} n/cm{sup 2}-s at one meter. Measurements of gamma ray production from deuterium impingement have shown tungsten to generate the fewest gamma rays; the primary components of the gas target have been constructed out of tungsten to decrease the number of gamma rays. To accommodate the high gas pressure, thin foil tungsten windows have been structurally reinforced with a tungsten support allowing for more than 60% beam transmission while greatly increasing the structural reliability of the thin windows. Extensive simulation and experimental testing have demonstrated the heating tolerances of the gas target thin windows and have shown that the peak temperature of the thin foils does not exceed 600 C, while the edges of the foil do not exceed 100 C, well within the limitsmore » of the foil windows and the gas sealing structures.« less

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
877926
Report Number(s):
UCRL-CONF-217015
TRN: US0601719
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: Presented at: IEEE Nuclear Science Syposium and Medical Imaging Conference, Farado, PR, United States, Oct 23 - Oct 29, 2005
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BEAM CURRENTS; DEUTERIUM; DEUTERONS; FAST NEUTRONS; HEATING; IMPINGEMENT; NEUTRON SOURCES; PRODUCTION; RELIABILITY; RESONANCE; SIMULATION; TARGETS; TESTING; TUNGSTEN

Citation Formats

Raas, W L, Blackburn, B, Boyd, E, Hall, J M, Kohse, G, Lanza, R, Rusnak, B, and Watterson, J. Design and Testing of a High Pressure Gas Target for Fast Neutron Resonance Radiography. United States: N. p., 2005. Web.
Raas, W L, Blackburn, B, Boyd, E, Hall, J M, Kohse, G, Lanza, R, Rusnak, B, & Watterson, J. Design and Testing of a High Pressure Gas Target for Fast Neutron Resonance Radiography. United States.
Raas, W L, Blackburn, B, Boyd, E, Hall, J M, Kohse, G, Lanza, R, Rusnak, B, and Watterson, J. Wed . "Design and Testing of a High Pressure Gas Target for Fast Neutron Resonance Radiography". United States. doi:. https://www.osti.gov/servlets/purl/877926.
@article{osti_877926,
title = {Design and Testing of a High Pressure Gas Target for Fast Neutron Resonance Radiography},
author = {Raas, W L and Blackburn, B and Boyd, E and Hall, J M and Kohse, G and Lanza, R and Rusnak, B and Watterson, J},
abstractNote = {A high pressure deuterium gas target has been designed to provide high-flux fast neutrons using the D(d,n){sup 3}He reaction for use as a neutron source. The deuterium gas cell holds 4 atm D{sub 2} gas at 298K and is projected to tolerate a beam current of {approx}50 {micro}A of 3.0 MeV deuterons for 8 hours of continuous use. The high-pressure gas cell is designed to provide a fast neutron flux on the order of 10{sup 5} n/cm{sup 2}-s at one meter. Measurements of gamma ray production from deuterium impingement have shown tungsten to generate the fewest gamma rays; the primary components of the gas target have been constructed out of tungsten to decrease the number of gamma rays. To accommodate the high gas pressure, thin foil tungsten windows have been structurally reinforced with a tungsten support allowing for more than 60% beam transmission while greatly increasing the structural reliability of the thin windows. Extensive simulation and experimental testing have demonstrated the heating tolerances of the gas target thin windows and have shown that the peak temperature of the thin foils does not exceed 600 C, while the edges of the foil do not exceed 100 C, well within the limits of the foil windows and the gas sealing structures.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Nov 09 00:00:00 EST 2005},
month = {Wed Nov 09 00:00:00 EST 2005}
}

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