Very High Energy Gamma Rays from the Vela Pulsar Direction
نویسندگان
چکیده
We have observed the Vela pulsar region at TeV energies using the 3.8 m imaging Čerenkov telescope near Woomera, South Australia between January 1993 and March 1995. Evidence of an unpulsed gamma-ray signal has been detected at the 5.8 σ level. The detected gamma-ray flux is (2.9± 0.5± 0.4)× 10 photons cm sec above 2.5± 1.0 TeV and the signal is consistent with steady emission over the two years. The gamma-ray emission region is offset from the Vela pulsar position to the southeast by about 0. 13. No pulsed emission modulated with the pulsar period has been detected and the 95 % confidence flux upper limit to the pulsed emission from the pulsar is (3.7± 0.7)× 10 photons cm sec above 2.5± 1.0 TeV. Subject headings: gamma rays: observations — ISM: individual (Vela SNR) — ISM: magnetic fields — pulsars: individual (Vela pulsar) — supernova remnants
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