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arXiv · 1704.01183

Investigation of Deuterium Loaded Materials Subject to X-Ray Exposure

Abstract

Results are presented from an exploratory study involving x-ray irradiation of select deuterated materials. Titanium deuteride (TiD2) plus deuterated polyethylene ([-CD2-]n; DPE), DPE alone, and for control, hydrogen-based polyethylene ([-CH2-]n; HPE) samples and nondeuterated titanium samples were exposed to x-ray irradiation. These samples were exposed to various energy levels from 65 to 280 kV with prescribed electron flux from 500 to 9000 micro-A impinging on a tungsten braking target, with total exposure times ranging from 55 to 280 min. Gamma activity was measured using a high-purity germanium (HPGe) detector, and for all samples no gamma activity above background was detected. Alpha and beta activities were measured using a gas proportional counter, and for select samples beta activity was measured with a liquid scintillator spectrometer. The majority of the deuterated materials subjected to the microfocus x-ray irradiation exhibited postexposure beta activity above background and several showed short-lived alpha activity. The HPE and nondeuterated titanium control samples exposed to the x-ray irradiation showed no postexposure alpha or beta activities above background. Several of the samples (SL10A, SL16, SL17A) showed beta activity above background with a greater than 4-sigma confidence level, months after exposure. Portions of SL10A, SL16, and SL17A samples were also scanned using a beta scintillator and found to have beta activity in the tritium energy band, continuing without noticeable decay for over 12 months. Beta scintillation investigation of as-received materials (before x-ray exposure) showed no beta activity in the tritium energy band, indicating the beta emitters were not in the starting materials.

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Theresa L. Benyo, Bruce M. Steinetz, Robert C. Hendricks, Richard E. Martin, Lawrence P. Forsley, Christopher C. Daniels, Arnon Chait, Vladimir Pines, Marianna Pines, Nicholas Penney, Tracy R. Kamm, Michael D. Becks. 2017-04-03. Investigation of Deuterium Loaded Materials Subject to X-Ray Exposure. https://arxiv.org/abs/1704.01183

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