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Profiles of dark-matter haloes at high redshift

A. Del Popolo
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Abstract

I study the evolution of haloes density profiles as a function of time in the SCDM and LCDM cosmologies. Following Del Popolo et al. (1999), I calculate the concentration parameter c=r_v/a and study its time evolution. For a given halo mass, I find that c(z) ~1/(1+z) both in the LCDM and SCDM cosmology, in agreement with Bullock et al. (1999) analytic model and N-body simulations. In both models, a(z) is roughly constant. The present model predicts a stronger evolution of c(z) with respect to Navarro et al. (1997) model. Finally I show some consequences of the result on galaxy modelling.

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A. Del Popolo. 2001-03-27. Profiles of dark-matter haloes at high redshift. https://doi.org/10.1046/j.1365-8711.2001.04539.x

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