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arXiv · 2212.08004

Cosmological probes of helium reionization

Selim C. Hotinli
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Abstract

Joint analysis of CMB and large-scale structure at high redshifts provide new and unique windows into unexplored epochs of early structure formation. Here, we demonstrate how cosmic infrared background and high-redshift galaxies can be jointly analysed with CMB to probe the epoch of helium reionization ($2<z<4$) on the light cone using kinetic Sunyaev Zel'dovich tomography. Characterising this epoch has great potential significance for understanding astrophysics of galaxy formation, quasar activity and formation of the super-massive black holes. We find a detection at $8-10\sigma$ can be expected from combinations of data from CCAT-prime, Vera Rubin Observatory and CMB-S4 in the upcoming years.

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Selim C. Hotinli. 2022-12-15. Cosmological probes of helium reionization. https://doi.org/10.1103/physrevd.108.043528

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