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Register a new userEnergetic $gamma$-rays from TeV scale dark matter annihilation resummed
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The annihilation cross section of TeV scale dark matter particles $chi^0$ with electroweak charges into photons is affected by large quantum corrections due to Sudakov logarithms and the Sommerfeld effect. We calculate the semi-inclusive photon energy spectrum in $chi^0chi^0to gamma+X$ in the vicinity of the maximal photon energy $E_gamma = m_chi$ with NLL accuracy in an all-order summation of the electroweak perturbative expansion adopting the pure wino model. This results in the most precise theoretical prediction of the annihilation rate for $gamma$-ray telescopes with photon energy resolution of parametric order $m_W^2/m_chi$ for photons with TeV energies.
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The annihilation cross section of weakly interacting TeV scale dark matter particles $chi^0$ 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 $chi^0chi^0to gamma+X$ in the vicinity of the maximal photon energy $E_gamma = m_chi$ with NLL accuracy from the case of narrow photon energy resolution $E^gamma_{rm res}$ of order $m_W^2/m_chi$ to intermediate resolution of order $E^gamma_{rm res} sim m_W$. 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.
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