Aluminum Relaxation as the Source of Excess Low Energy Events in Low Threshold Calorimeters

Abstract

A previously unexplained background called the Low Energy Excess (LEE) has negatively impacted the reach of a variety of low threshold calorimeters including light dark matter direct detection and coherent elastic neutrino-nucleus scattering experiments. The relaxation of stressed aluminium films as mediated by the motion of dislocations may account for these observations.