High-energy neutrino emission from x-ray binaries

Abstract

We show that high-energy neutrinos can be efficiently produced in X-ray binaries with relativistic jets and high-mass primary stars. We consider a system where the star presents a dense equatorial wind and the jet has a small content of relativistic protons. In this scenario, neutrinos and correlated gamma-rays result from $pp$ interactions and the subsequent pion decays. As a particular example we consider the microquasar LS I $+61$ 303. Above 1 TeV, we obtain a mean-orbital ${\ensuremath{\nu}}_{\ensuremath{\mu}}$-luminosity of $\ensuremath{\sim}5\text{ }{10}^{34}\text{ }\text{ }\mathrm{erg}/\mathrm{s}$ which can be related to an event rate of 4--5 muon-type neutrinos per kilometer-squared per year after considering the signal attenuation due to maximal neutrino oscillations. The maximal neutrino energies here considered will range between 20 and 85 TeV along the orbit. The local infrared photon field is responsible for opacity effects on the associated gamma radiation at high energies, but below 50 GeV the source could be detected by MAGIC telescope. GLAST observations at ${E}_{\ensuremath{\gamma}}g100\text{ }\text{ }\mathrm{MeV}$ should also reveal a strong source.