Temperature Structure and Mass-Temperature Scatter In Galaxy Clusters
  Precision cosmology studies based on wide-field surveys of galaxy clusters
benefit from constraints on intrinsic scatter in mass-observable relationships.
In principle, two-parameter models combining direct measurements of galaxy
cluster structural variation with mass proxies such as X-ray luminosity and
temperature can be used to constrain scatter in the relationship between the
mass proxy and the cluster's halo mass and to measure the redshift evolution of
that scatter. One candidate for quantifying cluster substructure is the ICM
temperature inhomogeneity inferred from X-ray spectral properties, an example
of which is T_HBR, the ratio of hardband to broadband spectral-fit
temperatures. In this paper we test the effectiveness of T_HBR as an indicator
of scatter in the mass-temperature relation using 118 galaxy clusters simulated
with radiative cooling and feedback. We find that, while T_HBR is correlated
with clusters' departures \delta lnT_X from the mean M-T_X relation, the effect
is modest.
