Precise yield of high-energy photons from Higgsino dark matter annihilation

The impact of electroweak Sudakov logarithms on the endpoint of the photon spectrum for wino dark matter annihilation was studied intensively over the last several years. In this work, we extend these results to Higgsino dark matter chi(0)(1). We achieve NLL ' resummation accuracy for narrow and intermediate spectral energy resolutions, of order mW2/m chi and m(W), respectively. This is the most accurate prediction to date for the yield of high-energy gamma-rays from chi(0)(1)chi(0)(1)-> gamma + X annihilation for the energy resolutions realized by current and next-generation telescopes. We also discuss for the first time the effect of power corrections in m(W)/m(chi) in this context and argue why they are not sizeable.