The OGLE View of Microlensing towards the Magellanic Clouds. I. A
  Trickle of Events in the OGLE-II LMC data
  We present the results from the OGLE-II survey (1996-2000) towards the Large
Magellanic Cloud (LMC), which has the aim of detecting the microlensing
phenomena caused by dark matter compact objects in the Galactic Halo (Machos).
  We use high resolution HST images of the OGLE fields and derive the
correction for the number of monitored stars in each field. This also yield
blending distributions which we use in 'catalogue level' Monte Carlo
simulations of the microlensing events in order to calculate the detection
efficiency of the events.
  We detect two candidates for microlensing events in the All Stars Sample,
which translates into an optical depth of 0.43+-0.33x 10e-7. If both events
were due to Macho the fraction of mass of compact dark matter objects in the
Galactic halo would be 8+-6 per cent. This optical depth, however, along with
the characteristics of the events, seems to be consistent with the self-lensing
scenario, i.e., self-lensing alone is sufficient to explain the observed
microlensing signal. Our results indicate a non-detection of Machos lensing
towards the LMC with an upper limit on their abundance in the Galactic halo of
19 per cent for M=0.4 Msun and 10 per cent for masses between 0.01 and 0.2
Msun.
