Dark Matter scattering in dielectrics

I will discuss a set of calculations of dark matter interactions with low threshold semi-conductor detectors such as SENSEI and superCDMS. As a warm-up, I'll show how to rephrase traditional DM-electron scattering calculations in terms of the energy loss function of the material. We will then apply this framework to compute the rate for the Migdal effect in semi-conductor targets. This is needed because the traditional calculations of the Migdal effect do not apply in low threshold semi-conductor detectors, as the delocalized nature of the valence electrons is not taken into account.