GAMMA-1 OBSERVATIONS OF THE GAMMA-RAY PULSAR PSR 0833-45 - PHASE DEPENDENCE OF THE LUMINOSITY

In the summer of 1990 and spring of 1991, the gamma-ray telescope Gamma 1 observed the Vela pulsar in hard gamma rays. Making use of up-to-date radio measurements, we have constructed light curves for the pulsar and conducted a preliminary timing analysis for gamma ray energies above 100 MeV. We discuss, in particular, the position of the most prominent features on the light curve in relation to the radio peak; we also discuss the possibility that the intensity of the pulsed emission is variable, based on two sets of observations taken six months apart. Finally, we compare our results with those obtained by the COS B group.