Large-scale detector testing for the GAPS Si(Li) Tracker

• Published in: arXiv.org 2023-09
• Main Authors: Xiao, Mengjiao, Stoessl, Achim, Roach, Brandon, Gerrity, Cory, Bouche, Ian, Bridges, Gabriel, Philip von Doetinchem, Hailey, Charles J, Kraych, Derik, Katt, Anika, Law, Michael, Alexander, Lowell, Martinez, Evan, Perez, Kerstin, Reed, Maggie, Rodriguez, Chelsea, Saffold, Nathan, Stringfield, Ceaser, Weiner, Hershel, Yee, Kelsey
• Format: Article
• Language: English
• Subjects: Arrays; Cryogenic temperature; Dark matter; Energy resolution; High temperature; Ionizing radiation; Lithium; Low cost; Nuclear physics; Operating temperature; Radiation detectors; Silicon
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2305.00283

Lithium-drifted silicon [Si(Li)] has been used for decades as an ionizing radiation detector in nuclear, particle, and astrophysical experiments, though such detectors have frequently been limited to small sizes (few cm\(^2\)) and cryogenic operating temperatures. The 10-cm-diameter Si(Li) detectors developed for the General Antiparticle Spectrometer (GAPS) balloon-borne dark matter experiment are novel particularly for their requirements of low cost, large sensitive area (~10 m\(^2\) for the full 1440-detector array), high temperatures (near -40\(\,^\circ\)C), and energy resolution below 4 keV FWHM for 20--100-keV x-rays. Previous works have discussed the manufacturing, passivation, and small-scale testing of prototype GAPS Si(Li) detectors. Here we show for the first time the results from detailed characterization of over 1100 flight detectors, illustrating the consistent intrinsic low-noise performance of a large sample of GAPS detectors. This work demonstrates the feasibility of large-area and low-cost Si(Li) detector arrays for next-generation astrophysics and nuclear physics applications.