Constraining galactic pγ interactions with cosmic ray electron and positron spectra

Abstract

High energy protons produced by various sources of cosmic rays, e.g., supernova remnants, pulsar wind nebulae, active galactic nuclei and gamma-ray bursts, participate in pγ and pp interactions. Although pp interactions may be the dominant mechanism in our Galaxy, it is unclear how important pγ process is. We show that the upper bound on the fraction of total number of protons participating in pγ interactions inside all Galactic astrophysical sources of cosmic rays is 10%.