Search for cosmic-ray boosted sub-MeV dark matter-electron scatterings in PandaX-4T

We report the first search for the elastic scatterings between cosmic-ray boosted sub-MeV dark matter and electrons in the PandaX-4T liquid xenon experiment. Sub-MeV dark matter particles can be accelerated by scattering with electrons in the cosmic rays and produce detectable electron recoil signals in the detector. Using the commissioning data from PandaX-4T of 0. 63~tonneyear exposure, we set new constraints on DM-electron scattering cross sections for DM masses ranging from 10~eV/c² to 3~keV/c².