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DOE OSTI · 2420654

Low-threshold sapphire detector for rare event searches

Verma, S.·Maludze, S.·Lee, M.·Chaudhuri, M.·Iyer, V.·Kashyap, V. K. S.·Kubik, A.·Lin, Y. -T.·Mahapatra, R.·Mirabolfathi, N.·Mishra, N.·Mohanty, B.·Neog, H.·Jastram, A.·Platt, M.
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Abstract

Low mass nuclear recoil dark matter and coherent-elastic-neutrino-nucleus-scattering (CE$v$NS) searches confront similar challenges in choosing ultra-low threshold and large-mass detectors. Here, we report experimental results from a 100 g single-crystal sapphire detector design with a diameter of 76 mm and thickness of 4 mm instrumented with transition edge sensors (TES). Sapphire is a crystal of aluminum oxide (Al 2 O) and has been found to be a good candidate for light mass dark matter search experiments due to its lower atomic mass compared to other detector materials such as germanium and silicon. This new phonon-assisted sapphire detector was characterized to yield a baseline recoil energy resolution of 28.4 ± 0.4 eV. The detector is designed to be sensitive to low-energy rare interactions with an intention to investigate the low-mass region of dark matter phase-space and search for CE$v$NS at the reactor site.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSCEvNSLow mass dark matterLow temperatureLow threshold detectorPhonon detector

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Verma, S., Maludze, S., Lee, M., Chaudhuri, M., Iyer, V., Kashyap, V. K. S., Kubik, A., Lin, Y. -T., Mahapatra, R., Mirabolfathi, N., Mishra, N., Mohanty, B., Neog, H., Jastram, A., Platt, M.. 2022-10-22. Low-threshold sapphire detector for rare event searches. https://doi.org/10.1016/j.nima.2022.167634

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