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Distance limit for a class of model gamma-ray burst sourcesIt is pointed out that MeV photons have actually been observed in bursts. These observations imply that the nonrelativistic sources cannot be further away than a few kpc from the sun and, therefore, must be galactic. The 27 April 1972 event observed by Apollo 16 shows at higher energies a power law spectrum with a possible line feature around 4 MeV. The optical depth of a homogeneous, isotropic radiation field is estimated with the aid of formulae used by Nikishov (1962) and Jauch and Rohrlich (1955). On the basis of an investigation of the various factors involved, it is tentatively suggested that the gamma-ray bursts which have been detected are galactic, but are in the majority of the cases not connected with unique irreversible star transformation. It appears also unlikely that the gamma-ray bursts are connected with galactic novae.
Document ID
Document Type
Reprint (Version printed in journal)
External Source(s)
Schmidt, W. K. H. (NASA Goddard Space Flight Center Laboratory for High Energy Astrophysics, Greenbelt, Md., United States)
Date Acquired
August 9, 2013
Publication Date
February 9, 1978
Publication Information
Publication: Nature
Volume: 271
Subject Category
Distribution Limits