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تسجيل مستخدم جديدGram-scale cryogenic calorimeters for rare-event searches
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The energy threshold of a cryogenic calorimeter can be lowered by reducing its size. This is of importance since the resulting increase in signal rate enables new approaches in rare-event searches, including the detection of MeV mass dark matter and coherent scattering of reactor or solar neutrinos. A scaling law for energy threshold vs. detector size is given. We analyze the possibility of lowering the threshold of a gram-scale cryogenic calorimeter to the few eV regime. A prototype 0.5 g Al$_2$O$_3$ device achieved an energy threshold of (${19.7pm0.1}$) eV, the lowest value reported for a macroscopic calorimeter.
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