A candidate M31/M32 intergalactic microlensing event

  title={A candidate M31/M32 intergalactic microlensing event},
  author={St{\'e}phane Paulin-Henriksson and Paul Baillon and Alain Bouquet and Bernard J. Carr and Michel Cr{\'e}z{\'e} and N. Wyn Evans and Yannick Giraud-H{\'e}raud and A. Gould and Paul C. Hewett and Jean Kaplan and Eamonn Kerins and Y. Le Du and A. L. Melchior and Steven J. Smartt and David Valls-Gabaud and T. de France and Cern and Queen Mary and University of London and Universit{\'e} de Bretagne-Sud and Oxford and Ohio State and I University of Cambridge and U. LiverpoolJohnMoores and Lerma and Observatoire de Paris and Observatoire de Midi-Pyrenees},
  journal={The Astrophysical Journal},
We report the discovery of a microlensing candidate projected 2'54'' from the center of M32, on the side closest to M31. The blue color (R-I = 0.00 ? 0.14) of the source argues strongly that it lies in the disk of M31, while the proximity of the line of sight to M32 implies that this galaxy is the most likely host of the lens. If this interpretation is correct, it would confirm previous arguments that M32 lies in front of M31. If more events are discovered in this direction in a dedicated… 

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