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DOE OSTI · 1872032

Design and Characterization of an Optically Segmented Single Volume Scatter Camera Module

Keefe, Kevin·Alhajaji, Hassam·Brubaker, Erik·Druetzler, Andrew·Galindo-Tellez, Aline·Learned, John·Maggi, Paul·Manfredi, Juan J.·Nishimura, Kurtis·Souza, Bejamin Pinto·Steele, John·Sweany, Melinda·Takahashi, Eric
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Abstract

Here, the optically segmented single volume scatter camera (OS-SVSC) aims to image neutron sources for nuclear nonproliferation applications using the kinematic reconstruction of elastic double-scatter events. We report on the design, construction, and calibration of one module of a new prototype. The module includes 16 EJ-204 organic plastic scintillating bars individually wrapped in Teflon tape, each measuring 0.5cx0.5cmx20cm . The scintillator array is coupled to two custom silicon photomultiplier (SiPM) boards consisting of a 2x8 array of SensL J-Series-60035 SiPMs, which are read out by a custom 16 channel DRS4 based digitizer board. The electrical crosstalk between SiPMs within the electronics chain is measured as 0.76%±0.11% among all 16 channels. We report the detector response of one module including interaction position, time, and energy, using two different optical coupling materials: EJ-560 silicone rubber optical coupling pads and EJ-550 optical coupling grease. We present results in terms of the overall mean and standard deviation of the z -position reconstruction and interaction time resolutions for all 16 bars in the module. We observed the 1σz -position resolution for gamma interactions in the 0.3–0.4 MeVee range to be 2.24 cm ± 1.10 cm and 1.45 cm ± 0.19 cm for silicone optical coupling pad and optical grease, respectively. The observed 1σ interaction time resolution is 265 ps ± 29 ps and 235 ps ± 10 ps for silicone optical coupling pad and optical grease, respectively.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSfast neutron imagingspecial nuclear material detection

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Keefe, Kevin, Alhajaji, Hassam, Brubaker, Erik, Druetzler, Andrew, Galindo-Tellez, Aline, Learned, John, Maggi, Paul, Manfredi, Juan J., Nishimura, Kurtis, Souza, Bejamin Pinto, Steele, John, Sweany, Melinda, Takahashi, Eric. 2022-05-10. Design and Characterization of an Optically Segmented Single Volume Scatter Camera Module. https://doi.org/10.1109/tns.2022.3172002

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