High-energy processes in starburst-driven winds

Abstract

Starburst galaxies generate large-scale winds powered by the activity in the starforming regions located in the galactic disks. Fragmentation of the disk produced bythe outbreak of the wind results in the formation of clouds. Bowshocks caused by thesupersonic outflow appear around such clouds. In this paper we discuss the accelerationof relativistic particles and the production of non-thermal radiation in such scenario.Cosmic rays accelerated at the bowshocks do not reach the highest energies, althoughthe high-energy luminosity generated is significant. We show that up to ∼ 10% of thegamma-ray emission in starbursts might come from these sources outside the galacticdisks. Discrete X-ray sources with a power-law component are also expected.