  The temperature profile (TP) of the intracluster medium (ICM) is of primeval
importance for deriving the dynamical parameters of the largest equilibrium
systems known in the universe, in particular their total mass profile.
Analytical models of the ICM often assume that the ICM is isothermal or
parametrize the TP with a polytropic index. This parameter is ajusted to
observations, but has in fact poor physical meaning for values other than 1 or
5/3, when considering monoatomic gases. In this article, I present a
theoretical model of a relaxed cluster where the TP is instead structured by
electronic thermal conduction. Neglecting cooling and heating terms, the
stationnary energy conservation equation reduces to a 2nd order differential
equation, whose resolution requires two boundary conditions, taken here as the
inner radius and the ratio between inner and outer temperature. Once these two
constants are chosen, the TP has a fixed analytical expression, which
reproduces nicely the observed ``universal'' TP obtained by Markevitch et al.
(1998) from ASCA data. Using observed X-ray surface brightnesses for two hot
clusters with spatially resolved TP, the local polytropic index and the hot gas
fraction profile are predicted and compare very well with ASCA observations
(Markevitch et al 1999). Moreover, the total density profile derived from
observed X-ray surface brightness, hydrostatic equilibrium and the
conduction-driven TP is very well fit by three analytical profiles found to
describe the structure of galactic or cluster halos in numerical simulations of
collisionless matter (Hernquist, 1991; Navarro et al. 1995, 1997; Burkert
1995). (abriged)
