Centaurus X-3: A source of high-energy gamma rays

Centaurus X-3 is a well studied high-mass accreting X-ray binary and a vari able source of high-energy gamma rays with energies from 100 MeV to 1 TeV. Previous results have suggested that the origin of the gamma rays is not th e immediate vicinity of the neutron star but is sited in the accretion disk , perhaps in an accretion wake. The Durham Mark 6 gamma-ray telescope has b een used to measure the gamma-ray flux from Centaurus X-3 with much higher sensitivity than previous ground-based measurements. The flux above similar to 400 GeV was measured to be (2 +/- 0.3) x 10(-11) cm(-2) s(-1) and appea rs constant over a period of 2-3 months. In 10 hours of observations there is no evidence for periodicity in the detected gamma rays at the X-ray spin period either from a site in the region of the neutron star or from any ot her potential site in the orbit.