SIMBAD references

2025ApJS..277...37U - Astrophys. J., Suppl. Ser., 277, 37 (2025/April-0)

SILVERRUSH. XIV. Lyα Luminosity Functions and Angular Correlation Functions from 20,000 Lyα Emitters at z ∼ 2.2-7.3 from up to 24 deg2 HSC-SSP and CHORUS Surveys: Linking the Postreionization Epoch to the Heart of Reionization.

UMEDA H., OUCHI M., KIKUTA S., HARIKANE Y., ONO Y., SHIBUYA T., INOUE A.K., SHIMASAKU K., LIANG Y., MATSUMOTO A., SAITO S., KUSAKABE H., KAGEURA Y. and NAKANE M.

Abstract (from CDS):

We present luminosity functions (LFs) and angular correlation functions (ACFs) derived from 18,960 Lyα emitters (LAEs) at z = 2.2-7.3 over a wide survey area of ≲24 deg2 that are identified in the narrowband data of the HSC-SSP and CHORUS surveys. Confirming the large sample with 241 spectroscopically identified LAEs, we determine Lyα LFs and ACFs in the brighter luminosity range down to 0.5L⋆, and confirm that our measurements are consistent with previous studies but offer significantly reduced statistical uncertainties. The improved precision of our ACFs allows us to clearly detect one-halo terms at some redshifts, and provides large-scale bias measurements that indicate host halo masses of ∼1011M⊙ over z ≃ 2-7. By comparing our Lyα LF (ACF) measurements with reionization models, we estimate the neutral hydrogen fractions in the intergalactic medium to be x_H i_ < 0.05 (= ${0.06}_{-0.03}^{+0.12}$) at z = 5.7 and x_H i_ = $0.1{5}_{-0.08}^{+0.10}$ (${0.21}_{-0.14}^{+0.19}$), $0.1{8}_{-0.12}^{+0.14}$, and $0.7{5}_{-0.13}^{+0.09}$ at z = 6.6, 7.0, and 7.3, respectively. Our findings suggest that the neutral hydrogen fraction remains relatively low, xH I ≲ 0.2, at z = 5-7, but increases sharply at z > 7, reaching x_H i_ ∼ 0.9 by z ≃ 8-9, as indicated by recent JWST studies. The combination of our results from LAE observations with recent JWST observations suggests that the major epoch of reionization occurred at z ∼ 7-8, likely driven by the emergence of massive sources emitting significant ionizing photons.

Abstract Copyright: © 2025. The Author(s). Published by the American Astronomical Society.

Journal keyword(s): Reionization - Galaxy formation - Luminosity function - Lyman-alpha galaxies

Simbad objects: 3

goto Full paper

goto View the references in ADS

To bookmark this query, right click on this link: simbad:2025ApJS..277...37U and select 'bookmark this link' or equivalent in the popup menu