EGRET Gamma-Ray Observations of the Crab P2/P1 Ratio
نویسندگان
چکیده
Recent observations of the Crab pulsar by the Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory show that the highenergy gamma-ray light curve has changed little over the lifetime of the instrument. Previous data collected by SAS-2 and COS-B in the years 1972-82, along with earlier EGRET data, suggested a 14 year sinusoidal variation in the flux ratio between the first and second peaks. The new data from EGRET indicate that the flux ratio is constant. Subject headings: gamma-rays: observations – pulsars : individual (Crab) Accepted Astrophysical Journal. Scheduled 20 Sep 1997. [email protected]
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