SILVERRUSH. XIV. Lya Luminosity Functions and Angular Correlation Functions from ~20,000 Lya Emitters at z~2.2-7.3 from upto 24 \({\rm deg}^2\) HSC-SSP and CHORUS Surveys: Linking the Post-Reionization Epoch to the Heart of Reionization

We present the luminosity functions (LFs) and angular correlation functions (ACFs) derived from 18,960 Ly\(\alpha\) emitters (LAEs) at \(z=2.2-7.3\) over a wide survey area of \(\lesssim24 {\rm deg^2}\) that are identified in the narrowband data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) and the Cosmic HydrOgen Reionization Unveiled with Subaru (CHORUS) surveys. Confirming the large sample with the 241 spectroscopically identified LAEs, we determine Ly\(\alpha\) LFs and ACFs in the brighter luminosity range down to \(0.5L_{\star}\), 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 hosting halo masses of \(\sim 10^{11} M_\odot\) over \(z\simeq 2-7\). By comparing our Ly\(\alpha\) LF (ACF) measurements with reionization models, we estimate the neutral hydrogen fractions in the intergalactic medium to be \(x_{\rm \HI} 7\), reaching \(x_{\rm \HI} \sim 0.9\) by \(z \simeq 8-9\), 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 around \(z \sim 7-8\), likely driven by the emergence of massive sources emitting significant ionizing photons.