The MACHO Project: Microlensing Results from 5.7 Years of Large Magellanic Cloud Observations

  title={The MACHO Project: Microlensing Results from 5.7 Years of Large Magellanic Cloud Observations},
  author={The Macho collaboration C. Alcock and Robyn A. Allsman and David Randall Alves and Timothy S. Axelrod and Andrew Cameron Becker and David P. Bennett and K. H. Cook and Neal Krishnakant Dalal and Andrew J. Drake and Kenneth C. Freeman and Marla Geha and Kim Griest and Matthew J. Lehner and Simon L. Marshall and Dante Minniti and Cailin Anne Nelson and Bruce A. Peterson and Piotr Popowski and Mark Robin Pratt and Peter Quinn and Christopher W. Stubbs and William J. Sutherland and Austin Bede Tomaney and Thor Vandehei and D. L. Welch},
  journal={The Astrophysical Journal},
We report on our search for microlensing toward the Large Magellanic Cloud (LMC). Analysis of 5.7 yr of photometry on 11.9 million stars in the LMC reveals 13-17 microlensing events. A detailed treatment of our detection efficiency shows that this is significantly more than the ~2-4 events expected from lensing by known stellar populations. The timescales () of the events range from 34 to 230 days. We estimate the microlensing optical depth toward the LMC from events with 2 < < 400 days to be… Expand
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