GAMMA-RAY OBSERVATIONS OF THE CRAB-NEBULA AT TEV ENERGIES

The Crab Nebula was observed in TeV gamma rays with the Whipple Observatory high-resolution atmospheric Cherenkov camera and a signal was detected at the 20-sigma-level. The energy spectrum derived has the form N(E) x dE = 2.5 x 10(-10) (E/0.4 TeV)-2.4 +/- 0.3 photons cm-2 s-1 TeV-1 between 0.4 and 4 TeV. There is no evidence for the pulsar periodicity, and the flux is steady on a monthly time scale. If this signal is used to optimize the technique for gamma-ray detection, then a flux one-tenth that of the Crab can be detected at the 3-sigma-level in 60 hr of integration time. For an on-axis source the angular resolution is shown to be +/- 0.-degrees-1.