Impact of Low-Energy Response to Nuclear Recoils in Dark Matter Detectors

D. -M. Mei; W. -Z. Wei; L. Wang

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arXiv · 1512.00694

Impact of Low-Energy Response to Nuclear Recoils in Dark Matter Detectors

D. -M. Mei·W. -Z. Wei·L. Wang

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Abstract

We report an absolute energy response function to electronic and nuclear recoils for germanium and liquid xenon detectors. As a result, we show that the detection energy threshold of nuclear recoils for a dual-phase xenon detector can be a few keV for a given number of detectable photoelectrons. We evaluate the average energy expended per electron-hole pair to be $\sim$3.32 eV, which sets a detection energy threshold of $\sim$2.15 keV for a germanium detector at 50 mini-Kelvin at 69 volts with a primary phonon frequency of 1 THz. The Fano factors of nuclear and electronic recoils that constrain the capability for discriminating nuclear recoils below 2-3 keV recoil energy for both technologies are different.

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D. -M. Mei, W. -Z. Wei, L. Wang. 2017-03-28. Impact of Low-Energy Response to Nuclear Recoils in Dark Matter Detectors. https://arxiv.org/abs/1512.00694

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