Evolution of the inner structure of Dark Matter Haloes

RUIZ, ANDRÉS NICOLÁS; SGRÓ, MARIO AGUSTÍN; DOMINGUEZ, MARIANO

Salta

Congreso; 53 Reunión Anual de la Asociación Argentina de Astronomía; 2010

Asociación Argentina de Astronomía

We present an ongoing study of the evolution of the inner structure of dark matter haloes in cosmological simulations in the standard LCDM scenario. We study the mass and redshift dependence of the NFW concentration parameter in individual dark matter haloes. In our data, the evolution of the concentration parameter follows a random behaviour quite different from the steady increase statistically predicted by Bullock’s et al 2002 rule. We also perform several tests in order to ensure that our model is representative of the real density profile and the precision level of our measurements. Finally we search for correlations between the temporal observed variations of the concentration parameter and several measures of the dynamical state of the dark matter haloes. The phenomena resembles the chaotic variations of the halo spin parameter described by Vitvitska et al 2002.