An attractor for the dynamical state of the intracluster medium
  Galaxy clusters provide us with important information about the cosmology of
our universe. Observations of the X-ray radiation or of the SZ effect allow us
to measure the density and temperature of the hot intergalactic medium between
the galaxies in a cluster, which then allow us to calculate the total mass of
the galaxy cluster. However, no simple connection between the density and the
temperature profiles has been identified. Here we use controlled
high-resolution numerical simulations to identify a relation between the
density and temperature of the gas in equilibrated galaxy clusters. We
demonstrate that the temperature-density relation is a real attractor, by
showing that a wide range of equilibrated structures all move towards the
attractor when perturbed and subsequently allowed to relax. For structures
which have undergone sufficient perturbations for this connection to hold, one
can therefore extract the mass profile directly from the X-ray intensity
profile.
