Extracting cosmological information from the angular power spectrum of the 2MASS Photometric Redshift catalogue

TL;DR

This paper performs a tomographic analysis of galaxy angular clustering using the 2MASS Photometric Redshift catalogue, estimating cosmological parameters and demonstrating the technique's value for future surveys.

Contribution

First tomographic analysis of galaxy clustering in the local Universe using 2MPZ, providing cosmological parameter estimates and validating the method for upcoming surveys.

Findings

Measured cosmological parameters consistent with Planck results.

Estimated galaxy bias increasing with redshift.

Confirmed the effectiveness of tomographic analysis for future surveys.

Abstract

Using the almost all-sky 2MASS Photometric Redshift catalogue (2MPZ) we perform for the first time a tomographic analysis of galaxy angular clustering in the local Universe ($z<0.24$). We estimate the angular auto- and cross-power spectra of 2MPZ galaxies in three photometric redshift bins, and use dedicated mock catalogues to assess their errors. We measure a subset of cosmological parameters, having fixed the others at their Planck values, namely the baryon fraction $f_{b}=0.14^{+0.09}_{-0.06}$, the total matter density parameter $\Omega_{\rm m}=0.30\pm 0.06$, and the effective linear bias of 2MPZ galaxies $b_{\rm eff}$, which grows from $1.1^{+0.3}_{-0.4}$ at $\langle z \rangle=0.05$ up to $2.1^{+0.3}_{-0.5}$ at $\langle z\rangle=0.2$, largely because of the flux-limited nature of the dataset. The results obtained here for the local Universe agree with those derived with the same methodology at higher redshifts, and confirm the importance of the tomographic technique for next-generation photometric surveys such as Euclid or LSST.