Detection of Pulsed Gamma Rays of ~10^{12} EV from the Pulsar in the Crab Nebula

The previous evidence we have given for the detection of pulsed -rays of 1012 eV from NP 0532 has been confirmed by an additional 99 drift scans on the Crab in 1971 November and December. Again, only those extensive air showers detected to be possibly initiated by -rays showed a 4.5 excess at the phase of the optical interpulse. The sum of these data and those reported previously yielded a 5.5 peak at the interpulse and a 3.5 peak at the main pulse, consistent with a pulsed flux F(E > 6.8 X 1011 eV) 1.25X 1011 photons 1 The ratio of interpulse to primary pulse is 3.5:1, and the spectrum appears consistent with an extrapolation from the X-ray data. Some implications of these results are discussed.