  A combination of the X-ray imaging and SZ measurements of clusters permits an
indirect determination of the radial temperature profiles of intracluster gas,
which requires no assumption about the dynamical properties and the equation of
state for clusters. A comparison of such a derived gas temperature with that
given by the X-ray spectral analysis constitutes an effective probe of
properties of intracluster gas. Using the available data of 31 clusters in
literature, we have performed the first comparison of the central gas
temperatures provided by the two methods. The good agreement between these two
independent temperature estimates suggests that the distribution of
intracluster gas is essentially consistent with isothermality characterized by
a mean polytropic index of gamma=0.9+-0.1.
