Strong Gravitational Lensing and Dynamical Dark Energy

Abstract

We study the strong gravitational lensing properties of galaxy clusters obtained from N-body simulations with different kind of Dark Energy (DE). We consider both dynamical DE, due to a scalar field self--interacting through Ratra-Peebles (RP) or SUGRA potentials, and DE with constant negative w=p/rho= -1 (LCDM). We have 12 high resolution lensing systems for each cosmological model with a mass greater than 5x10^{14} solar masses. Using a Ray Shooting technique we make a detailed analysis of the lensing properties of these clusters with particular attention to the number of arcs and their properties (magnification, length and width). We found that the number of giant arcs produced by galaxy clusters changes in a considerable way from LCDM models to Dynamical Dark Energy models with a RP or SUGRA potentials. These differences originate from the different epochs of cluster formation and from the non-linearity of the strong lensing effect. We suggest the Strong lensing is one of the best tool to discriminate among different kind of Dark Energy.Comment: 8 pages, 11 figures. Lensing map resolution improved and effects of resolution discussed. One more RP model analysed. Accepted for publication by MNRA