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 σ level. 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 σ level in 60 hr of integration time. For an on-axis source the angular resolution is shown to be ± 0.1°