EXOSAT observations of the hot gas in the A1060 cluster of galaxies

Abstract

We have used the EXOSAT Observatory to map and to obtain the X-ray spectrum of the hot gas in the A1060 cluster of galaxies. The density and temperature profiles of the intracluster gas have been determined by spherical deprojection of the X-ray surface brightness distribution obtained. We assume hydrostatic equilibrium and a cluster gravitational potential as described analytically by a King law, with a total binding mass of 10¹⁴ M⊚. The electron density and the temperature of the hot gas within a radius of 16 kpc from the cluster center are found to lie in the range (1.1-1.2) × 10^-2 cm ^-3 and (1.0-1.5) × 10⁷ K, respectively, when the effects of an extra" galaxy-like" potential are also included. We confirm the presence of cooling inflow in the central regions <70 kpc) of the cluster with mass accretion rate falling from 7-14 M⊚ yr^-1 at the periphery of the start of the cooling flow to 2-4 M⊚ yr^-1 in the innermost bin. The observed X-ray gas when extrapolated out to a radius of ~ 500 kpc has ~5% of the total binding mass.