EGRET Gamma-Ray Observations of the Crab P2/P1 Ratio

摘要

Recent observations of the Crab pulsar by the Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory show that the high-energy 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 19721982, along with earlier EGRET data, suggested a 14 yr sinusoidal variation in the flux ratio between the first and second peaks. The new data from EGRET indicate that the flux ratio is constant.