Resummed photon spectrum from dark matter annihilation for intermediate and narrow energy resolution
The annihilation cross section of weakly interacting TeV scale dark matter particles $χ^0$ into photons is affected by large quantum corrections due to electroweak Sudakov logarithms and the Sommerfeld effect. We extend our previous work on the resummation of the semi-inclusive photon energy spectrum in $χ^0χ^0\to γ+X$ in the vicinity of the maximal photon energy $E_γ= m_χ$ with NLL' accuracy from the case of narrow photon energy resolution $E^γ_{\rm res}$ of order $m_W^2/m_χ$ to intermediate resolution of order $E^γ_{\rm res} \sim m_W$. We also provide details on the previous narrow resolution calculation. The two calculations, performed in different effective field theory set-ups for the wino dark matter model, are then shown to match well, providing an accurate representation up to energy resolutions of about 300 GeV.