Matching resummed endpoint and continuum $\gamma$-ray spectra from dark-matter annihilation

For the minimal wino and Higgsino benchmark models we provide accurate energy spectra of high-energy photons from TeV scale dark-matter annihilation $\chi\chi\to \gamma+X$ by merging electroweak Sudakov resummation near maximal energy with the electroweak parton-shower PPPC4DM, and accounting for the Sommerfeld effect. Electroweak resummation significantly changes the shape of the photon-energy spectrum in the wide range $E_\gamma \sim (0.6\ldots 1)\, m_\chi$ and hence the form of the so-called "line-signal".