The flat density profiles of massive, and relaxed galaxy clusters
  In the present paper, we studied by means of the SIM introduced in Del Popolo
(2009), the total and DM density profiles, and the correlations among different
quantities, observed by Newman et al. (2012a,b), in seven massive and relaxed
clusters, namely MS2137, A963, A383, A611, A2537, A2667, A2390. Similarly to
Newman et al. (2012a,b), the total density profile, in the radius range 0.003 -
0.03$r_{200}$, has a mean total density profile in agreement with
dissipationless simulations. The slope of the DM profiles of all clusters is
flatter than -1. The slope, $\alpha$, has a maximum value (including errors) of
$\alpha=-0.88$ in the case of A2390, and minimum value $\alpha=-0.14$ for
A2537. The baryonic component dominates the mass distribution at radii $< 5-10$
kpc, while the outer distribution is dark matter dominated. We found an
anti-correlation among the slope $\alpha$, the effective radius, $R_e$, and the
BCG mass, and a correlation among the core radius $r_{core}$, and $R_e$.
Moreover, the mass in 100 kpc (mainly dark matter) is correlated with the mass
inside 5 kpc (mainly baryons).
  The behavior of the total mass density profile, the DM density profile, and
the quoted correlations can be understood in a double phase scenario. In the
first dissipative phase the proto-BCG forms, and in the second dissipationless
phase, dynamical friction between baryonic clumps (collapsing to the center)
and the DM halo flattens the inner slope of the density profile.
  In simple terms, the large scatter in the inner slope from cluster to
cluster, and the anti-correlation among the slope, $\alpha$ and $R_e$ is due to
the fact that in order to have a total mass density profile which is NFW-like,
clusters having more massive BCGs at their centers must contain less DM in
their center. Consequently the inner profile has a flatter slope.
