Density profiles of simulated galaxy cluster-sized dark matter haloes are analysed in the context of a recently introduced nonextensive theory of dark matter and gas density distributions .
Nonextensive statistics accounts for long-range interactions in gravitationally coupled systems and is derived from the fundamental concept of entropy generalisation .
The simulated profiles are determined down to radii of \approx 1 % of R _ { 200 } .
The general trend of the relaxed , spherically averaged profiles is accurately reproduced by the theory .
For the main free parameter \kappa , measuring the degree of coupling within the system , and linked to physical quantities as the heat capacity and the polytropic index of the self-gravitating ensembles , we find a value of -15 .
The significant advantage over empirical fitting functions is provided by the physical content of the nonextensive approach .