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Title: Initial Design Calculations for a Detection System that will Observe Resonant Excitation of the 680 keV state in 238U

Abstract

We present calculations and design considerations for a detection system that could be used to observe nuclear resonance fluorescence in {sup 238}U. This is intended as part of an experiment in which a nearly monochromatic beam of light incident on a thin foil of natural uranium resonantly populates the state at 680 keV in {sup 238}U. The beam of light is generated via Compton upscattering of laser light incident on a beam of relativistic electrons. This light source has excellent energy and angular resolution. In the current design study we suppose photons emitted following de-excitation of excited nuclei to be observed by a segmented array of BGO crystals. Monte Carlo calculations are used to inform estimates for the design and performance of this detector system. We find that each detector in this array should be shielded by about 2 cm of lead. The signal to background ratio for each of the BGO crystals is larger than ten. The probability that a single detector observes a resonant photon during a single pulse of the light source is near unity.

Authors:
;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
902615
Report Number(s):
UCRL-TR-227910
TRN: US0702981
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; DE-EXCITATION; DESIGN; DETECTION; ELECTRONS; EXCITATION; LASERS; LIGHT SOURCES; NATURAL URANIUM; NUCLEI; PERFORMANCE; PHOTONS; PROBABILITY; RESOLUTION; RESONANCE FLUORESCENCE

Citation Formats

Pruet, J, and Hagmann, C. Initial Design Calculations for a Detection System that will Observe Resonant Excitation of the 680 keV state in 238U. United States: N. p., 2007. Web. doi:10.2172/902615.
Pruet, J, & Hagmann, C. Initial Design Calculations for a Detection System that will Observe Resonant Excitation of the 680 keV state in 238U. United States. doi:10.2172/902615.
Pruet, J, and Hagmann, C. Fri . "Initial Design Calculations for a Detection System that will Observe Resonant Excitation of the 680 keV state in 238U". United States. doi:10.2172/902615. https://www.osti.gov/servlets/purl/902615.
@article{osti_902615,
title = {Initial Design Calculations for a Detection System that will Observe Resonant Excitation of the 680 keV state in 238U},
author = {Pruet, J and Hagmann, C},
abstractNote = {We present calculations and design considerations for a detection system that could be used to observe nuclear resonance fluorescence in {sup 238}U. This is intended as part of an experiment in which a nearly monochromatic beam of light incident on a thin foil of natural uranium resonantly populates the state at 680 keV in {sup 238}U. The beam of light is generated via Compton upscattering of laser light incident on a beam of relativistic electrons. This light source has excellent energy and angular resolution. In the current design study we suppose photons emitted following de-excitation of excited nuclei to be observed by a segmented array of BGO crystals. Monte Carlo calculations are used to inform estimates for the design and performance of this detector system. We find that each detector in this array should be shielded by about 2 cm of lead. The signal to background ratio for each of the BGO crystals is larger than ten. The probability that a single detector observes a resonant photon during a single pulse of the light source is near unity.},
doi = {10.2172/902615},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 26 00:00:00 EST 2007},
month = {Fri Jan 26 00:00:00 EST 2007}
}

Technical Report:

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