2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/9593The 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.14 p., LaTeX, 4 figures available on request, PAR-LPTHE 92 39/LPC 92 17Astrophysicstext