Energisation of interstellar media and cosmic ray production by jets from X-ray binaries

Abstract

Drawing on recent estimates of the power of jets from X-ray binary systems as a function of X-ray luminosity, combined with improved estimates of the relevant Log(N)-Log(L_X) luminosity functions, we calculate the total energy input to the interstellar medium (ISM) from these objects. The input of kinetic energy to the ISM via jets is dominated by those of the black hole systems, in contrast to the radiative input, which is dominated by accreting neutron stars. Summing the energy input from black hole jets L_J in the Milky Way, we find that it is likely to correspond to >1% of L_SNe, the time-averaged kinetic luminosity of supernovae, and >5% of L_CR, the cosmic ray luminosity. Given uncertainties in jet power estimates, significantly larger contributions are possible. Furthermore, in elliptical galaxies with comparable distributions of low mass X-ray binaries, but far fewer supernovae, the ratio L_J / L_SNe is likely to be larger by a factor of ~5. We conclude that jets from X-ray binaries may be an important, distributed, source of kinetic energy to the ISM in the form of relativistic shocks, and as a result are likely to be a major source of cosmic rays.