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Halo profiles from weakly nonlinear initial conditions

Ewa L. Lokas
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Abstract

Using weakly nonlinear conditional PDF for the density field around an overdense region we find that the expected density contrast around a peak is always smaller while its rms fluctuation larger than in the linear case. We apply these results to the spherical model of collapse as developed by Hoffman & Shaham (1985) and find that in the case of open Universe the effect of weakly nonlinear interactions is to decrease the scale from which a peak gathers mass and the mass itself as well as to steepen the final profile of the virialized protoobject.

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Ewa L. Lokas. 1997-11-12. Halo profiles from weakly nonlinear initial conditions. https://arxiv.org/abs/astro-ph/9711128

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