TY - JOUR

T1 - Probing Patchy Reionization with the Void Probability Function of Ly alpha Emitters

AU - Perez, Lucia. A. A.

AU - Malhotra, Sangeeta

AU - Rhoads, James. E. E.

AU - Laursen, Peter

AU - Wold, Isak G. B.

PY - 2022/12/1

Y1 - 2022/12/1

N2 - We probe what constraints for the global ionized hydrogen fraction the void probability function (VPF) clustering can give for the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) narrowband survey as a function of area. Neutral hydrogen acts like a fog for Ly alpha emission, and measuring the drop in the luminosity function of Ly alpha emitters (LAEs) has been used to constrain the ionization fraction in narrowband surveys. However, the clustering of LAEs is independent of the luminosity function's inherent evolution, and can offer additional constraints for reionization under different models. The VPF measures how likely a given circle is to be empty. It is a volume-averaged clustering statistic that traces the behavior of higher-order correlations, and its simplicity offers helpful frameworks for planning surveys. Using the Jensen et al. simulations of LAEs within various amounts of ionized intergalactic medium, we predict the behavior of the VPF in one (301 x 150.5 x 30 Mpc(3)), four (5.44 x 10(6) Mpc(3)), or eight (1.1 x 10(7) Mpc(3)) fields of LAGER imaging. We examine the VPF at 5 ' and 13 ', corresponding to the minimum scale implied by the LAE density and the separation of the 2D VPF from random, and the maximum scale from the eight-field 15.5 deg(2) LAGER area. We find that even a single DECam field of LAGER (2-3 deg(2)) could discriminate between mostly neutral versus ionized. Additionally, we find four fields allow for the distinction between 30%, 50%, and 95% ionized, and eight fields could even distinguish between 30%, 50%, 73%, and 95% ionized.

AB - We probe what constraints for the global ionized hydrogen fraction the void probability function (VPF) clustering can give for the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) narrowband survey as a function of area. Neutral hydrogen acts like a fog for Ly alpha emission, and measuring the drop in the luminosity function of Ly alpha emitters (LAEs) has been used to constrain the ionization fraction in narrowband surveys. However, the clustering of LAEs is independent of the luminosity function's inherent evolution, and can offer additional constraints for reionization under different models. The VPF measures how likely a given circle is to be empty. It is a volume-averaged clustering statistic that traces the behavior of higher-order correlations, and its simplicity offers helpful frameworks for planning surveys. Using the Jensen et al. simulations of LAEs within various amounts of ionized intergalactic medium, we predict the behavior of the VPF in one (301 x 150.5 x 30 Mpc(3)), four (5.44 x 10(6) Mpc(3)), or eight (1.1 x 10(7) Mpc(3)) fields of LAGER imaging. We examine the VPF at 5 ' and 13 ', corresponding to the minimum scale implied by the LAE density and the separation of the 2D VPF from random, and the maximum scale from the eight-field 15.5 deg(2) LAGER area. We find that even a single DECam field of LAGER (2-3 deg(2)) could discriminate between mostly neutral versus ionized. Additionally, we find four fields allow for the distinction between 30%, 50%, and 95% ionized, and eight fields could even distinguish between 30%, 50%, 73%, and 95% ionized.

KW - TO 7 IMPLICATIONS

KW - LUMINOSITY FUNCTION

KW - LYMAN-ALPHA

KW - COSMIC REIONIZATION

KW - EMITTING GALAXIES

KW - REDSHIFT Z

KW - EVOLUTION

KW - EPOCH

KW - END

KW - SPECTROSCOPY

U2 - 10.3847/1538-4357/ac9b57

DO - 10.3847/1538-4357/ac9b57

M3 - Journal article

VL - 940

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 102

ER -