Secondary photons from high-energy protons accelerated in hypernovae

Recent observations show that hypernovae may deposit some fraction of their kinetic energy in mildly relativistic ejecta. In the dissipation process of such ejecta in a stellar wind, cosmic-ray protons can be accelerated up to ∼10¹⁹ eV. We discuss the TeV to MeV gamma-ray and the X-ray photon signatures of cosmic rays accelerated in hypernovae. Secondary X-ray photons, emitted by electron-positron pairs produced via cascade processes due to high-energy protons, are the most promising targets for X-ray telescopes. Synchrotron photons emitted by protons can appear in the GeV band, requiring nearby (<40 Mpc) hypernovae for detection with GLAST. In addition, air Cerenkov telescopes may be able to detect regenerated TeV photons emitted by electron-positron pairs generated by CMB attenuation of π⁰-decay photons.