AGAPEROS : SEARCHES FOR MICROLENSING IN THE LMC WITH THE PIXEL METHOD. II.SELECTION OF POSSIBLE MICROLENSING EVENTS

We apply the pixel method of analysis (sometimes called ``pixel lensing'') to a small subset of the EROS-1\ microlensing observations of the bar of the Large Magellanic Cloud (LMC). The pixel method is designed to find microlensing events of unresolved source stars and had heretofore been applied only to M31 where essentially all sources are unresolved. With our analysis optimised for the detection of long-duration microlensing events due to 0.01-1 M_sun Machos, we detect no microlensing events and compute the corresponding detection efficiencies. We show that the pixel method, applied to crowded fields, should detect 10 to 20 times more microlensing events for M〉0.05 M_sun Machos compared to a classical analysis of the same data which latter monitors only resolved stars. In particular, we show that for a full halo of Machos in the mass range 0.1 - 0.5 M_sun, a pixel analysis of the three-year EROS-1 data set covering 0.39 deg(2) would yield =~ 4 events.