New strong bounds on sub-GeV dark matter from boosted and Migdal effects

Due to the low nuclear recoils, sub-GeV dark matter (DM) is usually beyond the sensitivity of the conventional DM direct detection experiments. The boosted and Migdal scattering mechanisms have been proposed as two new complementary avenues to search for light DM. In this study, we consider the momentum-transfer effect in the DM-nucleus scattering to derive the new bounds on sub-GeV DM for these two scenarios. We show that such an effect is sizable so that the existing bounds on the DM-nucleus scattering cross section can be improved significantly.

Automated summary

Due to low nuclear recoils, conventional direct detection experiments are not sensitive to sub-GeV dark matter (DM). Boosted and Migdal scattering mechanisms have been proposed as new complementary approaches for light DM searches. This study considers the momentum-transfer effect in DM-nucleus scattering and derives new bounds on sub-GeV DM for these two scenarios, showing significant improvement in the existing bounds on the DM-nucleus scattering cross section.