QSOgalaxy correlations induced by weak lensing in arbitrary FriedmannLemaître cosmologies
Abstract
We calculate the angular crosscorrelation function between background QSOs and foreground galaxies induced by the weak lensing effect of largescale structures. Results are given for arbitrary FriedmannLemaître cosmologies. The nonlinear growth of density perturbations is included. Compared with the linear growth, the nonlinear growth increases the correlation amplitude by about an order of magnitude in an Einsteinde Sitter universe, and by even more for lower Omega_0. The dependence of the correlation amplitude on the cosmological parameters strongly depends on the normalization of the power spectrum. The QSOgalaxy crosscorrelation function is most sensitive to density structures on scales in the range (110)h^1Mpc, where the normalization of the power spectrum to the observed cluster abundance appears most appropriate. In that case, the correlation strength changes by less than a factor of <~2 when Omega_0 varies between 0.3 and 1, quite independent of the value of Omega_Lambda. For Omega_0<~0.3, the correlation strength increases with decreasing Omega_0, and it scales approximately linearly with the Hubble constant h.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 November 1997
 DOI:
 10.1093/mnras/291.3.446
 arXiv:
 arXiv:astroph/9704217
 Bibcode:
 1997MNRAS.291..446D
 Keywords:

 Gravitational Lenses;
 Quasars;
 Dark Matter;
 Galactic Structure;
 Power Spectra;
 Formalism;
 Cosmology;
 Cross Correlation;
 Weighting Functions;
 Astrophysics;
 DARK MATTER;
 GRAVITATIONAL LENSING;
 LARGESCALE STRUCTURE OF UNIVERSE;
 Astrophysics
 EPrint:
 revised version, accepted by MNRAS