Spectral changes for local cosmic rays. II. The electron component and its interpretation

Abstract

This is the second paper on the spectral variations of cosmic rays over the local region of the Galaxy and deals with the electron component. The EGRET data on cosmic gamma rays below 150 MeV from the Compton Gamma Ray Observatory are analysed in the manner of flux ratios of two energy bands over the sky. Combined with the results on the proton component from the first paper, and a measure of confirmation from the authors' earlier analysis of COS B data, they favour an interpretation that adiabatic energy losses and reacceleration by old supernova remnants are responsible for the observed spectral variations. Other possibilities are also discussed. They suggest that the directly measured cosmic ray spectrum at the Earth is probably not the same as the average over the local region of the Galaxy.