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arXiv · 1003.4740

Halo model description of the non-linear dark matter power spectrum at $k \gg 1$ Mpc$^{-1}$

Carlo Giocoli·Matthias Bartelmann·Ravi K. Sheth·Marcello Cacciato
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Abstract

Accurate knowledge of the non-linear dark-matter power spectrum is important for understanding the large-scale structure of the Universe, the statistics of dark-matter haloes and their evolution, and cosmological gravitational lensing. We analytically model the dark-matter power spectrum and its cross-power spectrum with dark-matter haloes. Our model extends the halo-model formalism, including realistic substructure population within individual dark-matter haloes and the scatter of the concentration parameter at fixed halo mass. We consider three prescriptions for the mass-concentration relation and two for the substructure distribution in dark-matter haloes. We show that this extension of the halo model mainly increases the predicted power on the small scales, and is crucial for proper modeling the cosmological weak-lensing signal due to low-mass haloes. Our extended formalism shows how the halo model approach can be improved in accuracy as one increases the number of ingredients that are calibrated from n-body simulations.

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Carlo Giocoli, Matthias Bartelmann, Ravi K. Sheth, Marcello Cacciato. 2010-03-24. Halo model description of the non-linear dark matter power spectrum at $k \gg 1$ Mpc$^{-1}$. https://doi.org/10.1111/j.1365-2966.2010.17108.x

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