skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: HotSpotter? Neutron/Gamma Detector

Abstract

The HotSpotter{trademark} Neutron/Gamma Detector combines in a single detecting module high sensitivity to gamma rays up to 3 MeV and sensitivity to neutrons. Using a 15 mm cubic CdWO{sub 4} (cadmium tungstate) crystal mounted on a 25 mm photomultiplier, the instrument realizes a factor of 5 increased photopeak efficiency over NaI(Tl) at 1 MeV, and a factor of 2 improvement over CsI(Tl). The addition of a 0.5 mm layer of {sup 10}B- impregnated epoxy covering the crystal provides neutron sensitivity without sacrificing gamma ray spectroscopic characteristics. Neutrons are detected by the presence of the 478 keV gamma from the {sup 10}B(n,{alpha}){sup 7}Li* reaction. In this paper, we describe the electronics and software of the instrument, and some of its characteristics.

Authors:
Publication Date:
Research Org.:
Oak Ridge Y-12 Plant, Oak Ridge, TN (US)
Sponsoring Org.:
USDOE; USDOE Office of Defense Programs (DP) (US)
OSTI Identifier:
810878
Report Number(s):
Y/DX-2534
TRN: US0502441
DOE Contract Number:
AC05-00OR-22800
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 1 Apr 2003
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CADMIUM; EFFICIENCY; NEUTRONS; SENSITIVITY

Citation Formats

Bell, Z.W. HotSpotter? Neutron/Gamma Detector. United States: N. p., 2003. Web. doi:10.2172/810878.
Bell, Z.W. HotSpotter? Neutron/Gamma Detector. United States. doi:10.2172/810878.
Bell, Z.W. Tue . "HotSpotter? Neutron/Gamma Detector". United States. doi:10.2172/810878. https://www.osti.gov/servlets/purl/810878.
@article{osti_810878,
title = {HotSpotter? Neutron/Gamma Detector},
author = {Bell, Z.W.},
abstractNote = {The HotSpotter{trademark} Neutron/Gamma Detector combines in a single detecting module high sensitivity to gamma rays up to 3 MeV and sensitivity to neutrons. Using a 15 mm cubic CdWO{sub 4} (cadmium tungstate) crystal mounted on a 25 mm photomultiplier, the instrument realizes a factor of 5 increased photopeak efficiency over NaI(Tl) at 1 MeV, and a factor of 2 improvement over CsI(Tl). The addition of a 0.5 mm layer of {sup 10}B- impregnated epoxy covering the crystal provides neutron sensitivity without sacrificing gamma ray spectroscopic characteristics. Neutrons are detected by the presence of the 478 keV gamma from the {sup 10}B(n,{alpha}){sup 7}Li* reaction. In this paper, we describe the electronics and software of the instrument, and some of its characteristics.},
doi = {10.2172/810878},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Apr 01 00:00:00 EST 2003},
month = {Tue Apr 01 00:00:00 EST 2003}
}

Technical Report:

Save / Share:
  • A series of calibration experiments has been done to characterize an NE-213 liquid scintillator detector of photons ranging up to approx.7 MeV. Calibrated sources of /sup 24/Na, /sup 22/Na, /sup 60/Co, and /sup 137/Cs were used to infer the conversion factors as a function of electron energy, and detector efficiencies. In the latter effort, comparisons were made of the measured electron recoil spectra with their calculated counterpart. The code SANDYL was used and its results were modified slightly by folding in a normal distribution to account for the anticipated broadening due to variations in the location of light pulses withinmore » the scintillator. The calculated spectra were 0 to 10% above the experimental data. Higher energy gamma rays were generated by a Pu-Be source, which generated the 4.439-MeV line from /sup 12/C*, and the /sup 16/O(n,n')/sup 16/O* reaction, which generated among others the 6.130, 6.919, and 7.117 lines. We observed a marked nonlinearity of light pulse amplitude with electron energy at higher energies. Linearity was confirmed at and below 2.75 MeV, with an estimated threshold at 15 keV. The nonlinearity at higher energy will complicate the analysis.« less
  • The neutron and gamma-ray shielding requirements for a proposed neutrino system below the target station at the Rutherford Laboratory Spallation Neutron Source (SNS) are studied. The present shield below the station consists of 2 meters of iron and 1 meter of concrete, below which is chalk (CaCO/sub 3/). An underground bunker housing the neutrino detector system would require additional shielding consisting of 6 meters of the chalk plus approx. 3 meters of iron to reduce the number of high-energy (> approx. 7 MeV) neutrons and gamma rays entering the detector system to an acceptable level of approx. 1 per day.