Gamma-ray sources observations with the HAGAR telescope system in the Himalayas - Richard BRITTO - Tata Institute of Fundamental Research - MUMBAI (INDIA)

jeudi 25 juin 2009, 15:00 → 16:00 Europe/Paris

We have observed Crab nebula using the recently commissioned wave-front sampling high altitude (4270 m amsl) array, HAGAR, at Hanle in the Ladakh region of the Himalayas. Regular source observations have begun with the complete setup of 7 telescopes since Sept. 2008. HAGAR is the first array of atmospheric Cherenkov telescopes established at a so high altitude and was designed to reach a relatively low threshold with quite a low mirror area (31 sq m). Estimation of the sensitivity of the experiment is undergoing using several hours of data from the direction of crab nebula, the standard candle source of TeV gamma ray astronomy. Data were acquired using the On-source/Off-source mode and by comparing these sky regions the strength of the gamma-ray signal could be estimated. Gamma-ray events arrive close to telescope axis direction while the cosmic-ray background events arrive from the whole field of view. We discuss our analysis procedures for the estimate of arrival direction, estimate of gamma-ray flux from Crab nebula and the sensitivity of the HAGAR system. Also preliminary results on blazars 1es2344+514 and Mkn421 will be presented.

Slides HAGAR_Seminar_Britto_LPNHE.pdf