Interacting galaxies and cosmological parameters

UMR 5024, CNRS – Université Montpellier 2, GRAAL, CC 72, 34095 Montpellier Cedex 5, France e-mail: reboul@graal.univ-montp2.fr

Received: 21 July 2005
Accepted: 10 November 2005

Abstract

We propose a (physical)-geometrical method to measure and , the present rates of the density cosmological parameters for a Friedmann-Lemaître universe. The distribution of linear separations between two interacting galaxies, when both of them undergo a first massive starburst, is used as a standard of length. Statistical properties of the linear separations of such pairs of “interactivated” galaxies are estimated from the data in the Two Degree Field Galaxy Redshift Survey. Synthetic samples of interactivated pairs are generated with random orientations and a likely distribution of redshifts. The resolution of the inverse problem provides the probability densities of the retrieved cosmological parameters. The accuracies that can be achieved by that method on and are computed depending on the size of ongoing real samples. Observational prospects are investigated as the foreseeable surface densities on the sky and magnitudes of those objects.