Non-linear power spectra of dark and luminous matter in halo model of structure formation

TL;DR

This paper develops a semi-analytical halo model approach to accurately predict the non-linear power spectra of dark and luminous matter, validated against simulations and galaxy survey data.

Contribution

It introduces a new approximation relating non-linear to linear amplitudes and a novel method for computing halo concentration, improving power spectrum predictions.

Findings

Accurate semi-analytical predictions for dark matter power spectra.

Good agreement between model predictions and galaxy survey data.

Validated methods for different cosmologies like bLambdabCDM and bLambdabWDM.

Abstract

The late stages of large-scale structure evolution are treated semi-analytically within the framework of modified halo model. We suggest simple yet accurate approximation for relating the non-linear amplitude to linear one for spherical density perturbation. For halo concentration parameter, $c$, a new computation technique is proposed, which eliminates the need of interim evaluation of the $z_{col}$. Validity of the technique is proved for $\Lambda$CDM and $\Lambda$WDM cosmologies. Also, the parameters for Sheth-Tormen mass function are estimated. The modified and extended halo model is applied for determination of non-linear power spectrum of dark matter, as well as for galaxy power spectrum estimation. The semi-analytical techniques for dark matter power spectrum are 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, good accordance is found.