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Title: Multi-layer boron thin-film detectors for neutrons

Abstract

Intrinsic efficiencies of the multilayer boron detectors have been examined both theoretically and experimentally. It is shown that due to the charge loss in the boron layers, the practical efficiencies of most multi-layer {sup 10}B detectors are limited up to about 42%, much less than 77% of the 2 bar 2-inch diameter {sup 3}He detectors. It is suggested that the same charge loss mechanism will prevent essentially all substrate-based boron detectors from ever reaching the efficiencies of high-pressure {sup 3}He tubes, independent of the substrate geometry and material composition (including silicon). Meanwhile, the experimental data indicate that the multi-layer approach can increase the efficiencies up to the theoretical limit. Good n/{gamma} discrimination has also achieved using the ionization charnber technique.

Authors:
 [1];  [1]
  1. Los Alamos National Laboratory
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
993112
Report Number(s):
LA-UR-10-01382; LA-UR-10-1382
TRN: US1007968
DOE Contract Number:
AC52-06NA25396
Resource Type:
Conference
Resource Relation:
Conference: SORMA 2010 ; May 25, 2010 ; Ann Arbor, MI
Country of Publication:
United States
Language:
English
Subject:
73; BORON; GEOMETRY; IONIZATION; NEUTRONS; SILICON; SUBSTRATES; THIN FILMS; NEUTRON DETECTORS

Citation Formats

Wang, Zhehui, and Morris, Christopher L. Multi-layer boron thin-film detectors for neutrons. United States: N. p., 2010. Web.
Wang, Zhehui, & Morris, Christopher L. Multi-layer boron thin-film detectors for neutrons. United States.
Wang, Zhehui, and Morris, Christopher L. Fri . "Multi-layer boron thin-film detectors for neutrons". United States. doi:. https://www.osti.gov/servlets/purl/993112.
@article{osti_993112,
title = {Multi-layer boron thin-film detectors for neutrons},
author = {Wang, Zhehui and Morris, Christopher L},
abstractNote = {Intrinsic efficiencies of the multilayer boron detectors have been examined both theoretically and experimentally. It is shown that due to the charge loss in the boron layers, the practical efficiencies of most multi-layer {sup 10}B detectors are limited up to about 42%, much less than 77% of the 2 bar 2-inch diameter {sup 3}He detectors. It is suggested that the same charge loss mechanism will prevent essentially all substrate-based boron detectors from ever reaching the efficiencies of high-pressure {sup 3}He tubes, independent of the substrate geometry and material composition (including silicon). Meanwhile, the experimental data indicate that the multi-layer approach can increase the efficiencies up to the theoretical limit. Good n/{gamma} discrimination has also achieved using the ionization charnber technique.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 2010},
month = {Fri Jan 01 00:00:00 EST 2010}
}

Conference:
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