Speaker: Bannanje Sripathi Acharya, Tata Institute
Abstract: Work on VHE gamma-ray astronomy using the Atmospheric Cherenkov Technique started in India way back in 1969,soon after the discovery of pulsars. Over the years, steady improvements in telescope hardware have led to increase in the sensitivity and collection area as well as reduction in the energy threshold of the experiments. The latest in this series of experiments is the HiGRO project located at very high altitude (4.3km), at Hanle in the Ladakh region of Himalayas. In the first phase of this project 7 telescope array called HAGAR was installed the year 2008. It is an array of wavefront sampling non- imaging telescopes having a threshold energy of about 200 GeV for gamma-rays. This is the first ACT array operating at very high altitudes. A 21-m imaging telescope (called MACE), built by BARC group, will be commissioned at the same site adjascent to HAGAR array in this year. With MACE, the threshold energy of gamma-rays is expec to be about a few tens of GeV. Regular observations of galactic and extra galactic objects using HAGAR are going on since October 2008. I shall describe the status the HiGRO project at Hanle and the recent results obtained using the HAGAR array.