Relatore
Descrizione
We study dark matter scattering off ${}^2$H and ${}^4$He nuclei, assuming DM to be composed by weak interacting massive particles, WIMPs. In order to parametrize the WIMP-nucleon interaction the chiral effective field theory ($\chi$EFT) approach is used. Considering only interactions invariant under parity, charge conjugation and time reversal, we examine five interaction types: scalar, pseudoscalar, vector, axial and tensor. Scattering amplitudes between two nucleons and a WIMP are calculated up to second chiral order, and used to calculate the nuclei responses. We apply this program to calculate the interaction rate as function of the WIMP mass and of the magnitude of the WIMP-quark coupling constants. From our study, we conclude that the scalar nuclear response functions result much greater than the others due to theirs large combination of low energy constants. We also verify that the leading order contributions are dominant in this low energy process.
