We present stellar and dark matter ( DM ) density profiles for a sample of seven massive , relaxed galaxy clusters derived from strong and weak gravitational lensing and resolved stellar kinematic observations within the centrally-located brightest cluster galaxies ( BCGs ) .
In Paper I of the series , we demonstrated that the total density profile derived from these data , which span three decades in radius , is consistent with numerical DM-only simulations at radii \gtrsim 5 - 10 kpc , despite the significant contribution of stellar material in the core .
Here we decompose the inner mass profiles of these clusters into stellar and dark components .
Parametrizing the DM density profile as a power law \rho _ { \textrm { DM } } \propto r ^ { - \beta } on small scales , we find a mean slope \langle \beta \rangle = 0.50 \pm 0.10 ~ { } \textrm { ( random ) } ~ { } ^ { +0.14 } _ { -0.13 } ~ { } % \textrm { ( systematic ) } .
Alternatively , cored Navarro–Frenk–White ( NFW ) profiles with \langle \log r _ { \textrm { core } } / \textrm { kpc } \rangle = 1.14 \pm 0.13 ^ { +0.14 } _ { -0.22 } provide an equally good description .
These density profiles are significantly shallower than canonical NFW models at radii \lesssim 30 kpc , comparable to the effective radii of the BCGs .
The inner DM profile is correlated with the distribution of stars in the BCG , suggesting a connection between the inner halo and the assembly of stars in the central galaxy .
The stellar mass-to-light ratio inferred from lensing and stellar dynamics is consistent with that inferred using stellar population synthesis models if a Salpeter initial mass function is adopted .
We compare these results to theories describing the interaction between baryons and DM in cluster cores , including adiabatic contraction models and the possible effects of galaxy mergers and active galactic nucleus feedback , and evaluate possible signatures of alternative DM candidates .