2024/11/14 by Ayodeji Ibitoye, Ibitoye, Ayodeji, Furen Deng +7
Mathematics · Physics and Astronomy · #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Solar and Space Plasma Dynamics #Statistical and numerical algorithms
paper · pdf · doi:10.48550/arxiv.2411.09437
openalex publication_date 2024/11/14 · openalex created_date 2024/11/17 · openalex updated_date 2026/07/28
The 21 cm emission from neutral hydrogen surveys holds great potential as a valuable method for exploring the large-scale structure of the Universe. In this paper, we forecast for the cross-correlation between the Thermal Sunyaev-Zel'dovich (SZ) fluctuations as probed by the Planck satellite, and fluctuations in the HI brightness temperature as probed by the ground-based Five-hundred-meter Aperture Spherical Telescope (FAST), to trace the connection between galaxy clusters and the HI large-scale structure. Assuming that the measurement is limited by instrumental noise rather than by foreground, we estimate the potential detectability of the cross-correlation signal and their improvement in the measurement of the HI cosmic density, the hydrostatic mass bias parameter, and the universal pressure profile (UPP) parameters. We obtain a constraint on the cosmic neutral hydrogen density parameter significantly to σ(Ω\rm HI) = 1.0 × 10-6. We also find that the average halo masses contributing to the \rm HI-y cross-power spectrum in the one-halo regime is ∼ 1.5× 1014 M\odot. Our results also show that the HI-SZ cross-correlation has great potential to probe the distribution of neutral hydrogen (HI) within halos at low redshift.