Detection of brown dwarfs by the micro-lensing of unresolved stars
  The presence of brown dwarfs in the dark galactic halo could be detected through their gravitational lensing effect and experiments under way monitor about one million stars to observe a few lensing events per year. We show that if the photon flux from a galaxy is measured with a good precision, it is not necessary to resolve the stars and besides more events could be observed. 
Paul Baillon, Alain Bouquet, Yannick Giraud-H\'eraud and Jean Kaplan