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Title: Wide Bandgap Semiconductor Detector Optimization for Flash X-Ray Measurements

Abstract

Charge trapping, resulting in a decreased and spatially dependent electric field, has long been a concern for wide bandgap semiconductor detectors. While significant work has been performed to characterize this degradation at varying temperatures and radiation environments, this work concentrates upon examining the event-to-event response in a flash X-ray environment. The following work investigates if charge trapping is a problem for CZT detectors, with particular emphasis on flash X-ray radiation fields at cold temperatures. Results are compared to a non-flash radiation field, using an Am-241 alpha source and similar temperature transitions. Our ability to determine if a response change occurred was hampered by the repeatability of our flash X-ray systems; a small response change was observed with the Am-241 source. Due to contrast of these results, we are in the process of revisiting the Am-241 measurements in the presence of a high radiation environment. If the response change is more pronounced in the high radiation environment, a similar test will be performed in the flash X-ray environment.

Authors:
 [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1409799
Report Number(s):
LA-UR-17-30557
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; CZT; Charge Trapping; Flash X-ray

Citation Formats

Roecker, Caleb Daniel, and Schirato, Richard C. Wide Bandgap Semiconductor Detector Optimization for Flash X-Ray Measurements. United States: N. p., 2017. Web. doi:10.2172/1409799.
Roecker, Caleb Daniel, & Schirato, Richard C. Wide Bandgap Semiconductor Detector Optimization for Flash X-Ray Measurements. United States. doi:10.2172/1409799.
Roecker, Caleb Daniel, and Schirato, Richard C. 2017. "Wide Bandgap Semiconductor Detector Optimization for Flash X-Ray Measurements". United States. doi:10.2172/1409799. https://www.osti.gov/servlets/purl/1409799.
@article{osti_1409799,
title = {Wide Bandgap Semiconductor Detector Optimization for Flash X-Ray Measurements},
author = {Roecker, Caleb Daniel and Schirato, Richard C.},
abstractNote = {Charge trapping, resulting in a decreased and spatially dependent electric field, has long been a concern for wide bandgap semiconductor detectors. While significant work has been performed to characterize this degradation at varying temperatures and radiation environments, this work concentrates upon examining the event-to-event response in a flash X-ray environment. The following work investigates if charge trapping is a problem for CZT detectors, with particular emphasis on flash X-ray radiation fields at cold temperatures. Results are compared to a non-flash radiation field, using an Am-241 alpha source and similar temperature transitions. Our ability to determine if a response change occurred was hampered by the repeatability of our flash X-ray systems; a small response change was observed with the Am-241 source. Due to contrast of these results, we are in the process of revisiting the Am-241 measurements in the presence of a high radiation environment. If the response change is more pronounced in the high radiation environment, a similar test will be performed in the flash X-ray environment.},
doi = {10.2172/1409799},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Technical Report:

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