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arXiv · 2405.06815

Exploring Large-Volume GAGG Scintillators for use in MeV Gamma-Ray Astrophysics

Daniel Shy·Richard Woolf·Bernard Phlips·Mary Johnson-Rambert·Emily Kong
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Abstract

Gamma-ray astrophysics in the MeV band is an exciting field in astronomy due to its potential for multi-messenger astrophysics. It has, however, remained under-explored when compared to other wavelengths. One reason for this observational gap is the difficulties with measuring these high-energy photons and the requirement of large amounts of detection material. In this work, we investigate the usage of large-volume GAGG scintillators for use as a calorimeter in future MeV telescopes. We developed a $5\times5$ array calorimeter utilizing $1\times1\times6 \ \mathrm{cm}^3$ GAGG crystals with onsemi C-series SiPM readout. We tested the calorimeter at the High Intensity Gamma-ray Facility (HIGS) with monoenergetic beams ranging from $2-25 \ \mathrm{MeV}$. Finally, we also investigate larger $1\times1\times8 \ \mathrm{cm}^3$ crystals and characterize their response across their depth when their surface treatment is either polished or frosted.

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Daniel Shy, Richard Woolf, Bernard Phlips, Mary Johnson-Rambert, Emily Kong. 2024-05-10. Exploring Large-Volume GAGG Scintillators for use in MeV Gamma-Ray Astrophysics. https://arxiv.org/abs/2405.06815

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