Migdal Effect in Dark Matter Direct Detection Experiments

Jul 23, 2017
40 pages
Published in:
  • JHEP 03 (2018) 194
  • Published: Mar 30, 2018
e-Print:
Report number:
  • IPMU17-0100

Citations per year

2010201420182022202501020304050
Abstract: (Springer)
The elastic scattering of an atomic nucleus plays a central role in dark matter direct detection experiments. In those experiments, it is usually assumed that the atomic electrons around the nucleus of the target material immediately follow the motion of the recoil nucleus. In reality, however, it takes some time for the electrons to catch up, which results in ionization and excitation of the atoms. In previous studies, those effects are taken into account by using the so-called Migdal’s approach, in which the final state ionization/excitation are treated separately from the nuclear recoil. In this paper, we reformulate the Migdal’s approach so that the “atomic recoil” cross section is obtained coherently, where we make transparent the energy-momentum conservation and the probability conservation. We show that the final state ionization/excitation can enhance the detectability of rather light dark matter in the GeV mass range via the nuclear scattering. We also discuss the coherent neutrino-nucleus scattering, where the same effects are expected.
Note:
  • calculation error in coherent neutrino-nucleus scattering fixed
  • Beyond Standard Model
  • Dark matter
  • Dark Matter and Double Beta Decay (experiments)
  • Electroweak interaction
  • dark matter: direct detection
  • nucleus: recoil
  • atom: excited state
  • neutrino nucleus: coherent interaction
  • energy-momentum: conservation law
  • ionization