Speaker
Description
The growing interest in the interactions between dark matter particles and electrons has received a further boost by the observation of an excess in electron recoil events in the XENON1T experiment. Of particular interest are dark matter models in which the scattering process is inelastic, such that the ground state can upscatter into an excited state. The subsequent exothermic downscattering of such excited states on electrons can lead to observable signals in direct detection experiments and gives a good fit to the XENON1T excess. In this talk, I will discuss terrestrial upscattering, i.e. inelastic scattering of dark matter particles on nuclei in the Earth, as a plausible origin of such excited states. I will demonstrate that both analytical and Monte Carlo methods allow for a detailed prediction of the excited density and velocity distribution. These results show a time dependence of the flux of excited states resulting from the rotation of the Earth. This daily modulation offers an intriguing opportunity to distinguish this mechanism from alternative explanations of the XENON1T excess and to additionally determine the DM mass.
This talk will be based on https://arxiv.org/abs/2112.06930.
