2005A&A...433..787J

We report our first microlensing candidate NMS-E1 towards M 31 from the data accumulated during the four years of Nainital Microlensing Survey. Cousin R and I band observations of ∼13'x13' field in the direction of M 31 have been carried out since 1998 and data is analysed using the pixel technique proposed by the AGAPE collaboration. NMS-E1 lies in the disk of M 31 at α=0^h43^m33.3s and δ=+41°06'44'', about 15.5 arcmin to the South-East direction of the center of M 31. The degenerate Paczynski fit gives a half intensity duration of ∼59-days. The photometric analysis of the candidate shows that it reached R∼20.1mag at the time of maximum brightness and the colour of the source star was estimated to be (R-I)₀∼1.1mag. The microlensing candidate is blended by red variable stars; consequently the light curves do not strictly follow the characteristic Paczynski shape and achromatic nature. However its long period monitoring and similar behaviour in R and I bands supports its microlensing nature.