Speaker
Description
We report new results on interactions of sub-GeV dark matter particles with electrons using data from a small dual-phase xenon time projection chamber operated at the Earth's surface 1. We consider scattering both on electrons and nuclei in the Earth’s crust, atmosphere, and shielding materials to compute the attenuation of the dark matter flux by the atmosphere and the 2. With an exposure of $\sim15\,\mathrm{g}\,\mathrm{days}$ and based on an ionisation-only event selection and no background subtraction, we evaluate the data in terms of various models, including interactions mediated by a heavy and ultralight dark photon as well as through an electric dipole moment 3. For the case of a heavy dark photon mediator, we exclude new parameter space for dark matter particle masses in the range $100-400\,\mathrm{MeV}$.