First Cosmological Constraints from the Joint Analysis of Galaxy Clustering and the Kinetic Sunyaev-Zel'dovich Effect
Abstract
We perform the first joint analysis of the galaxy clustering (GC) and the kinetic Sunyaev-Zel'dovich (kSZ) effect to simultaneously constrain cosmological and astrophysical parameters in this work, utilizing a combination of the Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) map and the Constant Stellar Mass (CMASS) galaxy sample. As a complementary probe to the galaxy density power spectrum, we incorporate the pairwise kSZ power spectrum detected with a high signal-to-noise ratio (S/N $\sim 7$) to derive constraints on cosmological parameters ($H_0 = 71.16^{+5.09}_{-5.50}$, $\Omega_{\rm m} = 0.276^{+0.086}_{-0.067}$, $w_0 = -0.971^{+0.236}_{-0.380}$) and the average optical depth of the galaxy sample ($\lg\bar{\tau} = -4.22 \pm +0.09$). Compared to the GC-only analysis, the joint analysis yields tighter constraints on these cosmological parameters: the Figures of Merits (FoMs) improve by 29.3%, 32.3% and 21.5% for the $H_0$--$\Omega_{\rm m}$, $H_0$--$w_0$ and $\Omega_{\rm m}$--$w_0$ contours. For the first time, we demonstrate the complementary applicability of the kSZ effect in constrain cosmological parameters from real observational data.