High-energy γ rays of cosmic origin
- 15 May 1968
- journal article
- Published by Canadian Science Publishing in Canadian Journal of Physics
- Vol. 46 (10), S484-S487
- https://doi.org/10.1139/p68-276
Abstract
A stack of nuclear emulsions flown over Hyderabad (vertical geomagnetic cutoff rigidity 16.9 GV), India, under 6 g/cm2 of residual air has been used to set upper limits to the flux of γ rays of cosmic origin. The integral flux values obtained are 13 × 10−4, 6 × 10−4, 2.6 × 10−4, 1.4 × 10−4, 0.6 × 10−4, and 0.3 × 10−4 photons (em2 s sr)−1 for energies greater than 50 MeV, 100 MeV, 2 GeV, 5 GeV, 10 GeV, and 50 GeV respectively. Using these data and those of Kraushaar et al. (1965), it seems unlikely that cosmic-ray collisions in meta-galactic space can be an important source of electrons needed to explain the finite flux of cosmic X rays as due to the inverse Compton scattering of these electrons with photons of the universal blackbody radiation at 3 °K; such collisions would predict a flux of γ rays much in excess of the upper limits obtained in the energy region 50–100 MeV.Keywords
This publication has 4 references indexed in Scilit:
- Recent observations on cosmic electrons and their consequences on different cosmic ray models and related astrophysical quantitiesProceedings of the Indian Academy of Sciences - Section A, 1967
- Reported Cosmic Gamma-Ray Source In CygnusPhysical Review Letters, 1967
- Evidence for a Source of Primary Gamma RaysPhysical Review Letters, 1966
- Electron Component of the Primary Cosmic Radiation at Energies ≳15 GeVPhysical Review Letters, 1965