Yurij Kulinich, Bohdan Novosyadlyj, Stepan Apunevych
The paper represents a comprehensive treatment of late stages of large-scale structure evolution within the framework of halo model. A number of modifications to basic theory are suggested. We have engineered simple yet accurate approximation to relate the amplitude of non-linear spherical density perturbation to the one of the linear. The theory for final stages of spherical overdensity evolution is revised in order to re-evaluate the dependences of collapse and critical overdensity parameters, $\delta_{col}$, $\delta_{ta}$ and $\delta_{min}$, on redshift and other cosmological parameters. A new technique is proposed for straightforward computation of halo concentration parameter, $c$, without need to evaluate the $z_{col}$. Validity of the technique is proved for a number of $\Lambda$CDM and $\Lambda$WDM cosmologies. The parameters for Sheth-Tormen mass function are estimated, as well as new approximation is constructed for the dependence of subhalo mass function on initial power spectrum. The modified and extended halo model is applied to the determination the non-linear dark matter and galaxy power spectra. The semi-analytical estimation of dark matter power spectrum is verified by comparison with data from numerical simulations. Also the predictions for the galaxy power spectra are confronted with 'observed' data from PSCz and SDSS galaxy catalogs. Quite good accordance is found.
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http://arxiv.org/abs/1203.5297
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