Direct detection of sub-GeV mass dark matter which scatters off nuclei has long been challenging due to loss of experimental sensitivity in this region of parameter space. However, sensitivity can be regained by exploiting the Migdal effect: the ionisation or excitation of atomic electrons after a nuclear scattering event. I describe the necessity of revisiting previous calculations of the Migdal effect to provide more accurate predictions which allow for large nuclear recoil velocities and incorporate the effects of multiple ionisation. I will also discuss the landscape of measurements seeking to confirm the presence of the Migdal effect in neutron scattering experiments. In addition, I will show how new bounds on sub-GeV, hadronically interacting dark matter can be derived from Big Bang Nucleosynthesis, improving on current astrophysical constraints by orders of magnitude.

This talk is part also of the Evolving Beyond the Standard Model TH institute