Turbulence in the SuperModel: Mass Reconstruction with Nonthermal Pressure for Abell 1835. (arXiv:1305.3020v1 [astro-ph.CO])

Turbulence in the SuperModel: Mass Reconstruction with Nonthermal Pressure for Abell 1835. (arXiv:1305.3020v1 [astro-ph.CO]):
The total mass derived from X-ray emission is biased low in a large number of
clusters when compared with the mass estimated via strong and weak lensing.
Suzaku and Chandra observations out to the virial radius report in several
relaxed clusters steep temperature gradients that on assuming pure thermal
hydrostatic equilibrium imply an unphysically decreasing mass profile.
Moreover, the gas mass fraction appears to be inconsistent with the cosmic
value measured from the CMB. Such findings can be interpreted as an evidence
for an additional nonthermal pressure in the outskirts of these clusters. This
nonthermal component may be due to turbulence stirred by residual bulk motions
of extragalactic gas infalling into the cluster. Here we present a SuperModel
analysis of Abell 1835 observed by Chandra out to the virial radius. The
SuperModel formalism can include in the equilibrium a nonthermal component
whose level and distribution are derived imposing that the gas mass fraction
f_{gas} equals the cosmic value at the virial radius. Including such a
nonthermal component, we reconstruct from X rays an increasing mass profile
consistent with the hydrostatic equilibrium also in the cluster outskirts and
in agreement at the virial boundary with the weak lensing value. The increasing
f_{gas} profile confirms that the baryons are not missing but located at the
cluster outskirts.