Speaker
Description
We investigated stau-antistau annihilation into heavy quarks in the phenomenological MSSM within the DM@NLO collaboration. This SUSY-QCD precision calculation, enhanced by a QED Sommerfeld resummation, turned out to have several interesting applications: Claiming the lightest neutralino to be a main dark matter constituent, there are promising, non-excluded SUSY scenarios that demand higher-order corrections of stau-coannihilations when computing the relic density. On the other hand, also in gravitino dark matter physics we show the important role of the staus, whose NLO corrections are inevitable for reliable predictions.
Moreover, we illustrate the often neglected dependence of the cross section on renormalisation scheme and scale. Our variations aim to show how strongly the prediction of the dark matter relic density is affected by such theoretical uncertainties, which can be cured by taking higher-order corrections into account.
Summary
The talk aims to illustrate the important role of stau (co-)annihilation for both neutralino and gravitino dark matter physics, especially taking theoretical uncertainties of renormalisation schemes and scales at different orders into account.
