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 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 ($H_0=70.82_{-5.01}^{+4.94}$, ${\Omega }_{\mathrm{m}}=0.290_{-0.068}^{+0.092}$, $w_0=-1.038_{-0.437}^{+0.245}$) and the average optical depth of the galaxy sample ($\lg \bar{\tau }=-4.24\pm 0.10$). Compared to the GC-only analysis, the joint analysis yields tighter constraints on these cosmological parameters: the Figures of Merit improve by 20.5\%, 19.7\% and 10.0\% for the $H_0$--${\Omega }_{\mathrm{m}}$, $H_0$--$w_0$ and ${\Omega }_{\mathrm{m}}$--$w_0$ contours, respectively. For the first time, we demonstrate the complementary applicability of the kSZ effect in constraining cosmological parameters from real observational data.

26 pages, 18 figures, ApJL accepted. Correct several bugs in the theoretical models, add one appendix explaining and validating the covariance matrix calculation. The improvements of the FoMs decrease, but the main conclusions remain unchanged