Observation of the Fermi pulsar catalog at TeV energies with the Tibet air shower experiment

Abstract

Using the Tibet-III air shower array, we search for steady TeV γ-rays from 18 pulsars in the Fermi Large Area Telescope pulsar catalog. Among them, we observe 8 sources including the Crab instead of the expected 0.41 sources at a significance of 2 σ or more excess. Under the assumption of Poisson distribution, the chance probability is estimated to be 1.4 × 10 -8. When the Crab is excluded, it becomes 1.8 × 10 -7. These low chance probabilities clearly show that the Fermi pulsars have a statistically significant correlations with TeV γ-ray excesses. © Author(s) 2011.