GeV gamma-rays and TeV neutrinos from very massive compact binary systems: The case of WR 20a

Abstract

Massive Wolf-Rayet stars in a compact binary systems are characterised by very strong winds which collide creating a shock wave. If the wind nuclei accelerated at the shock can reach large enough energies, they suffer disintegration in collisions with soft thermal radiation from the massive stars injecting relativistic protons and neutrons. Protons collide with the matter of the wind and a fraction of neutrons colide with the massive stars producing gamma-rays and neutrinos. We calculate the gamma-rays fluxes from the inverse Compton pair cascades, initiated by primary gamma-rays and leptons produced by protons, and the neutrino fluxes produced by protons and neutrons for the example compact massive binary WR 20a. From normalization of the gamma-ray spectra to the fluxes of the EGRET sources, 2EG J1021-5835 and 2EG J1049-5847, we conclude that this massive binary can be detected by the IceCube type neutrino detector with the event rate between a few up to a few tens per km^2 per yr.