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arXiv · 1306.3210

Dark matter halo formation in the multicomponent dark matter models

Abstract

This work investigates a set of cosmological collisionless N-body simulations with featured power spectra of initial perturbations in the context of the core-cusp and satellites problems. On the studied power spectra some scales of fluctuations were suppressed. Such spectral features can be caused by multicomponent dark matter. The density profiles innermost resolved slopes $α\equiv d \log(ρ) /d \log(r) $ of the five largest haloes were measured and its dependence on the parameters of the suppression was traced. In a certain range of the parameters the slopes flatten from initial value of about -1.2 to -0.6 or even to -0.2 in one of the cases. This qualitatively demonstrates that (i) profiles shape depends on initial power spectrum and (ii) this effect may be responsible for the solution of the core-cusp problem. The suppression of some part of the initial power spectrum also leads to the decrease of the number of massive subhaloes.

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Vadim Semenov, Sergey Pilipenko, Andrei Doroshkevich, Vladimir Lukash, Elena Mikheeva. 2013-06-13. Dark matter halo formation in the multicomponent dark matter models. https://arxiv.org/abs/1306.3210

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