EGRET Sources
نویسنده
چکیده
We compute the variation of the beaming fraction with the e ciency of high energy -ray production in the outer gap pulsar model of Romani and Yadigaroglu. This allows us to correct the uxes observed for pulsars in the EGRET band and to derive a simple estimate of the variation of e ciency with age. Integration of this model over the population of young neutron stars gives the expected number of -ray pulsars along with their distributions in age and distance. This model also shows that many of the unidenti ed EGRET plane sources should be pulsars, and predicts the -ray uxes of known radio pulsars. The contribution of unresolved pulsars to the background ux in the EGRET band is found to be about 5 %. Subject headings: pulsars | gamma rays | statistics
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