Universal thermodynamic properties of the intracluster medium over two
  decades in radius in the X-COP sample
  The hot plasma in galaxy clusters is expected to be heated to high
temperatures through shocks and adiabatic compression. The thermodynamical
properties of the gas encode information on the processes leading to the
thermalization of the gas in the cluster's potential well as well as
non-gravitational processes such as gas cooling, AGN feedback and kinetic
energy. In this work we present the radial profiles of the thermodynamic
properties of the intracluster medium (ICM) out to the virial radius for a
sample of 12 galaxy clusters selected from the Planck all-sky survey. We
determine the universal profiles of gas density, temperature, pressure, and
entropy over more than two decades in radius. We exploit jointly X-ray
information from XMM and Sunyaev-Zel'dovich constraints from Planck to recover
thermodynamic properties out to 2 R500. We provide average functional forms for
the radial dependence of the main quantities and quantify the slope and
intrinsic scatter of the population as a function of radius. We find that gas
density and pressure profiles steepen steadily with radius, in excellent
agreement with previous observational results. Entropy profiles beyond R500
closely follow the predictions for the gravitational collapse of structures.
The scatter in all thermodynamical quantities reaches a minimum in the range
[0.2-0.8] R500 and increases outwards. Somewhat surprisingly, we find that
pressure is substantially more scattered than temperature and density. Our
results indicate that once accreting substructures are properly excised, the
properties of the ICM beyond the cooling region R > 0.3 R500) follow remarkably
well the predictions of simple gravitational collapse and require little
non-gravitational corrections.
