* Astronomy

Title: Microlensing events from the 11-year observations of the Wendelstein Calar Alto Pixellensing Project
Author: C.-H. Lee (1,2), A. Riffeser (1,2), S. Seitz (1,2), R. Bender (1,2), J. Koppenhoefer (2,1) ((1) University Observatory Munich, (2) Max Planck Institute for Extraterrestrial Physics)

We present the results of the decade-long M31 observation from the Wendelstein Calar Alto Pixellensing Project (WeCAPP). WeCAPP has monitored M31 from 1997 till 2008 in both R- and I-filters, thus provides the longest baseline of all M31 microlensing surveys. The data are analysed with the difference imaging analysis, which is most suitable to study variability in crowded stellar fields. We extracted light curves based on each pixel, and devised selection criteria that are optimized to identify microlensing events. This leads to 10 new events, and sums up to a total of 12 microlensing events from WeCAPP, for which we derive their timescales, flux excesses, and colours from their light curves. The colour of the lensed stars fall between (R-I) = 0.56 to 1.36, with a median of 1.0 mag, in agreement with our expectation that the sources are most likely bright, red stars at post main-sequence stage. The event FWHM timescales range from 0.5 to 14 days, with a median of 3 days, in good agreement with predictions based on the model of Riffeser et al. (2006).

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