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The Very High Energy Gamma Ray Astronomy (VHE) is a rapidly evolving branch of modern astronomy, which covers the range from about 50 GeV to several tens of TeV from the ground. In the past years, the second generation instruments firmly established a growing and varied list of sources including plerions, supernova remnants and active galactic nuclei, and started to study some fundamental questions such as the origin of cosmic rays or the emission mechanisms of the active galactic nuclei. New results now include the first VHE unidentified sources as well as more puzzling sources such as the Galactic center. The arrival of new generation instruments (HESS, CANGAROO III, VERITAS, MAGIC) already gives a impressive look at the near future. Here we attempt to summarize the current status of the field. We briefly describe the instruments and analysis techniques, and give an outlook on the sources detected sofar.
In this work we study how the cosmological parameter, the Hubble constant $H_0$, can be constrained by observation of very high energy (VHE) $gamma$-rays at the TeV scale. The VHE $gamma$-rays experience attenuation by background radiation field thro
A report is made on a comprehensive observation of a burst-like $gamma$-ray emission from thunderclouds on the Sea of Japan, during strong thunderstorms on 2007 January 6. The detected emission, lasting for $sim$40 seconds, preceded cloud-to-ground l
Centaurus X-3 is a well-studied high-mass accreting X-ray binary and a variable source of high energy gamma rays with energies from 100 MeV to 1 TeV. Previous results have suggested that the origin of the gamma rays is not the immediate vicinity of t
We have observed the Vela pulsar region at TeV energies using the 3.8 m imaging Cherenkov telescope near Woomera, South Australia every year since 1992. This is the first concerted search for pulsed and unpulsed emission from the Vela region, and the
We have observed the Vela pulsar region at TeV energies using the 3.8 m imaging Cherenkov 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 sigma level.