Cosmic Ray Boosted Sub-GeV Gravitationally Interacting Dark Matter in
  Direct Detection
  Detections of non-gravitational interactions of massive dark matter (DM) with
visible sector so far have given null results. The DM may communicate with the
ordinary matter only through gravitational interaction. Besides, the majority
of traditional direct detections have poor sensitivities for light DM because
of the small recoil energy. Thanks to the high energy cosmic rays (CRs), the
light DM can be boosted by scattering with CRs and thus may be detected in the
ongoing experiments. In this work, we derive the exclusion limits on the cosmic
ray boosted sub-GeV DM with gravitational mediator from the Xenon1T data. It
turns out that a sizable region of such a cosmic ray boosted DM can be excluded
by the current data.
