Search for microlensing events towards M31 galaxy

Abstract

M31, the prominent galaxy of the Local Group, is located at a distance of about 700 kpc. Due to its convenient orientation, it is an alluring target for gravitational microlensing to search for massive astrophysical compact halo objects (MACHOs), in both the Galactic halo and its own halo. We have carried out the observations of the suburb of M31 galaxy using the 104-cm Sampurnanand Telescope of the State Observatory, Nainital, India. The observations have been accumulated for about hundred nights spanning over 800 days during 1998-2001. After the initial tests and preliminary analysis of the first two years data we have detected some possible M31 Cepheid variables of period between 10 to 85 days. Also using pixel method we have got an irregular variable and further analysis is in progress to detect the lensing events in the observed region.