Explaining the XENON1T excess with Luminous Dark Matter
  We show that the excess in electron recoil events seen by the XENON1T
experiment can be explained by relatively low-mass Luminous Dark Matter
candidate. The dark matter scatters inelastically in the detector (or the
surrounding rock), to produce a heavier dark state with a ~2.75 keV mass
splitting. This heavier state then decays within the detector, producing a peak
in the electron recoil spectrum which is a good fit to the observed excess. We
comment on the ability of future direct detection datasets to differentiate
this model from other Beyond the Standard Model scenarios, and from possible
tritium backgrounds, including the use of diurnal modulation, multi-channel
signals etc.,~as possible distinguishing features of this scenario.
