THE EFFECT OF WEAK LENSING ON THE ANGULAR-CORRELATION FUNCTION OF FAINT GALAXIES

The angular correlation function omega (theta) of faint galaxies is af fected both by non-linear gravitational evolution and by magnification bias resulting from gravitational lensing. We compute the resulting o mega (theta) for different cosmological models and show how its shape and redshift evolution depend on Omega and Lambda. For galaxies at red shift greater than 1 (R magnitude fainter than about 24), magnificatio n bias can significantly enhance or suppress omega(theta), depending o n the slope of the number-magnitude relation. We show, for example, ho w it changes the ratio of omega(theta) for two galaxy samples with dif ferent number count slopes.