Galactic Bulge microlensing optical depth from EROS-2

  title={Galactic Bulge microlensing optical depth from EROS-2},
  author={Clarisse Hamadache and Laurent Le Guillou and Patrick Tisserand and Cristina Afonso and J-N. Albert and Johannes Andersen and R'eza Ansari and Eric Aubourg and P. Bareyre and Jean Philippe Beaulieu and Xavier Charlot and Ch. Coutures and Roger Ferlet and Pascal Fouqu'e and J. F. Glicenstein and Bertrand Goldman and Andrew P. Gould and David S. Graff and M. Gros and Jacques Haissinski and Jan Otto de Kat and {\'E}. Lesquoy and C{\'e}cile Loup and Ch. Magneville and Jean Baptiste Marquette and Eric Maurice and Anaelle J. Maury and Alain Milsztajn and Marc Moniez and Nathalie Palanque-Delabrouille and Olivier Perdereau and Y. R. Rahal and Joshua Rich and Michel Spiro and Alfred Vidal-Madjar and Laurent G. Vigroux and S. Zylberajch},
  journal={Astronomy and Astrophysics},
We present a new EROS-2 measurement of the microlensing optical depth toward the Galactic Bulge. Light curves of $5.6\times 10^{6}$ clump-giant stars distributed over $66 \deg^2$ of the Bulge were monitored during seven Bulge seasons. 120 events were found with apparent amplifications greater than 1.6 and Einstein radius crossing times in the range $5 {\rm d} 

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