Department of Earth and Space Sciences, University of Science and Technology of China, Hefei, China
Laboratory for Astrophysics and Space Research, Enrico Fermi Institute, University of Chicago, USA
Abstract:
We calculate the spectrum of the diffuse cosmic gamma ray in the single and double leaky box models for several galactic distribution laws of cosmic rays and hdydrogen. The results show that LI Ti-pei's distribution law for the cosmic rays is the best and that the number of interstellar hydrogen molecules should be less than Gordon's value divided by 1.7. The observed spectrum of gamma rays can be reproduced by a suitable choice of the galactic distributions within certain ranges.