Speaker
Description
About forty (Mrk 421, Mrk 501, 1ES 1959+650, PG 1553+113 and others) northern TeV extragalactic sources have been discovered during last twenty five years. Most of them (2/3) we are monitoring in Abastumani Observatory during 20 years using 125-cm and dedicated 70-cm meniscus telescopes. All observations (over 3500 nights) have been conducted with Apogee Ap6E and SBIG ST-6 CCD cameras in BVRI bands. The frames have been reduced using Daophot II and homogenous light curves have been constructed. The amplitudes of long-term variability are within 0.3-1.5 magnitudes. Few sources show Intra-day variability within 0.05-0.15 magnitudes, while intra-night/micro-variability is below 0.05 magnitudes. The extensive multi-wavelength campaigns with Whipple, VERITAS, HESS and MAGIC have also been conducted.
