Strong Lensing in Abell 1703: Constraints on the Slope of the Inner Dark Matter Distribution - AstrophysicsReportar como inadecuado

Strong Lensing in Abell 1703: Constraints on the Slope of the Inner Dark Matter Distribution - Astrophysics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: In this article, we apply strong lensing techniques in Abell 1703, a massiveX-ray luminous galaxy cluster at z=0.28. Our analysis is based on imaging databoth from space and ground in 8 bands, complemented with a spectroscopicsurvey. Abell 1703 looks rather circular from the general shape of its multiplyimaged systems and present a dominant giant elliptical cD galaxy in its centre.This cluster exhibits a remarkable bright -central ring- formed by 4 brightimages at z {spec}=0.888 located very close to the cD galaxy, providingobservational constraints that are potentially very interesting to probe thecentral mass distribution. The stellar contribution from the cD galaxy ~1.2510^{12} M {sun} within 7- is accounted for in our parametric mass modelling,and the underlying smooth dark matter component distribution is described usinga generalized NFW profile parametrized with a central logarithmic slope \alpha.We find that within the range where observational constraints are present from~5- to ~50-, the slope of the dark matter distribution in Abell1703 is equalto 1.09^{+0.05} {-0.11} 3\sigma confidence level. The concentration parameteris equal to c {200} ~ 3.5, and the scale radius is constrained to be largerthan the region where observational constraints are available. Within thisradius, the 2D mass is equal to M50-=2.4 10^{14} M {\sun}. We cannot draw anyconclusions on cosmological models at this point since we lack results fromrealistic numerical simulations containing baryons to make a proper comparison.We advocate the need for a sample of observed and simulated unimodal relaxedgalaxy clusters in order to make reliable comparisons, and potentially providea test of cosmological models.

Autor: M. Limousin, J. Richard, J.-P. Kneib, H. Brink, R. Pello, E. Jullo, H. Tu, J. Sommer-Larsen, E. Egami, M. J. Michalowski, R. Caba


Documentos relacionados