A&A 439, 465-477 (2005)
Tracing the X-ray emitting intra-cluster medium of clusters of galaxies beyond rD. M. Neumann
AIM - Unité Mixte de Recherche CEA - CNRS - Université Paris VII - UMR N° 7158 CEA/Saclay; DSM/DAPNIA/Service d'Astrophysique, CEA/Saclay, L'Orme des Merisiers, Bât. 709, 91191 Gif-sur-Yvette, France
(Received 8 March 2005 / Accepted 2 May 2005 )
We present in this paper a study of a sample of 14 nearby clusters of galaxies ( 0.06<z<0.1) observed with the ROSAT/PSPC. We only select clusters with low galactic absorption ( 1020 cm-2) in order to trace the hot X-ray emitting intra-cluster medium (ICM) out to large radii. We convert the X-ray surface brightness profiles of the clusters into emission measure profiles scaled to the classical scaling relations based on the spherical collapse model. We sort the clusters into different temperature bins and stack the scaled emission measure (ScEM) profiles of clusters belonging to the same bin together. This method enhances the statistics of the profiles - especially in outer regions. The stacked profiles allow us to observe a signal out to radii r>r200.
Key words: galaxies: clusters: general -- cosmology: observations -- dark matter -- large-scale structure of Universe -- X-rays: galaxies: clusters
© ESO 2005