Chandra observations of the galaxy cluster Abell 1835

We present the analysis of 30 ks of Chandra observations of the galaxy clus ter Abell 1835. Overall, the X-ray image shows a relaxed morphology, althou gh we detect substructure in the inner 30-kpc radius. Spectral analysis sho ws a steep drop in the X-ray gas temperature from similar to 12 keV in the outer regions of the cluster to similar to4 keV in the core. The Chandra da ta provide tight constraints on the gravitational potential of the cluster which can be parametrized by a Navarro, Frenk & White model. The X-ray data allow us to measure the X-ray gas mass fraction as a function of radius, l eading to a determination of the cosmic matter density of Omega (m) = 0.40 +/-0.09 h(50)(-0.5). The projected mass within a radius of similar to 150 k pc implied by the presence of gravitationally lensed arcs in the cluster is in good agreement with the mass models preferred by the Chandra data. We f ind a radiative cooling time of the X-ray gas in the centre of Abell 1835 o f about 3 x 10(8) yr. Cooling-flow model fits to the Chandra spectrum and a deprojection analysis of the Chandra image both indicate the presence of a young cooling flow (similar to6 x 10(8) yr) with an integrated mass deposi tion rate of 230(-50)(+80) M-circle dot yr(-1) within a radius of 30 kpc. W e discuss the implications of our results in the light of recent Reflection Grating Spectrograph (RGS) observations of Abell 1835 with XMM-Newton.