Probing Dark Matter Particles from Evaporating Primordial Black Holes via Electron Scattering in the CDEX-10 Experiment

Dark matter (DM) is a major constituent of the Universe. However, no definite evidence of DM particles (denoted as ``χ") has been found in DM direct detection (DD) experiments to date. There is a novel concept of detecting χ from evaporating primordial black holes (PBHs). We search for χ emitted from PBHs by investigating their interaction with target electrons. The examined PBH masses range from 1×10¹⁵ to 7×10¹⁶ g under the current limits of PBH abundance fPBH. Using 205.4 kg·day data obtained from the CDEX-10 experiment conducted in the China Jinping Underground Laboratory, we exclude the χ--electron (χ--e) elastic-scattering cross section σχ e ~ 5×10⁻²⁹ cm² for χ with a mass mχ 0.1 keV from our results. With the higher radiation background but lower energy threshold (160 eV), CDEX-10 fill a part of the gap in the previous work. If (mχ, σχ e) can be determined in the future, DD experiments are expected to impose strong constraints on fPBH for large MPBHs.