The Evolution of the Ultraluminous Ly-alpha Luminosity Function over z=5.7-6.6

Abstract

Ultraluminous Lyman alpha (Lya) emitting galaxies (ULLAEs) with log L (Lya)>43.5 erg/s near the epoch of reionization (z>5) make up the bright end of the LAE luminosity function (LF) and may provide insight into the process of reionization, including the formation of ionized bubbles around these extreme systems. We present a spectroscopic LF for ULLAEs at z=5.7. We used data from the HEROES ~45 sq. deg Subaru Hyper Suprime-Cam survey, which is centered on the North Ecliptic Pole and has both broadband (grizY) and narrowband (NB816 and NB921) imaging, to select candidate ULLAEs based on a NB816 excess and a strong broadband Lyman break. We spectroscopically observed 17 ULLAE candidates with DEIMOS on Keck II. We confirmed 12 as LAEs at z=5.7, 9 of which are ULLAEs. The remaining sources are an AGN at z=5.7, an [OIII]5007 emitter at z=0.63, a red star, and two spectroscopic non-detections. Using the 9 confirmed ULLAEs, we construct a ULLAE LF at z=5.7. After applying a comprehensive incompleteness correction, we compare our new z=5.7 LF with our recent z=6.6 LF and with other LFs from the literature to look for evolution at the ultraluminous end. We find the overall ratio of the z=5.7 to z=6.6 ULLAE comoving number densities to be 1.92 (+1.12, -0.71), which corresponds to a LF offset of 0.28 (+0.20, -0.20) dex.

Accepted for publication in ApJ. 13 pages, 8 Figures, 3 Tables. v2 integrates an erratum to correct the coordinates of NEP5.7AGN. This change has been made directly in the article text, tables, and figures, and does not affect the results or conclusions of the work

References in corpus (3)

• The Subaru/XMM-Newton Deep Survey (SXDS). IV. Evolution of Lya Emitters from z=3.1 to 5.7 in the 1 deg^2 Field: Luminosity Functions and AGN
• Identification of the brightest Lyα emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era
• The Ultraluminous Lyman Alpha Luminosity Function at z=6.6

Cited by in corpus (16)

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• Peering into cosmic reionization: the Ly$\alpha$ visibility evolution from galaxies at $z$ = 4.5-8.5 with JWST
• The Magellan M2FS Spectroscopic Survey of High-$z$ Galaxies: Lyα Emitters at $z\approx 6.6$ and the Evolution of Lyα Luminosity Function over $z\approx 5.7-6.6$
• Crucial Factors for Lyα Transmission in the Reionizing Intergalactic Medium: Infall Motion, HII Bubble Size, and Self-shielded Systems
• An Hα Impression of Lyα Galaxies at $z\simeq 6$ with Deep JWST/NIRCam Imaging
• The THESAN project: Lyman-alpha emitter luminosity function calibration
• HEROES: The Hawaii eROSITA Ecliptic Pole Survey Catalog
• First upper limits on the 21-cm signal power spectrum of neutral hydrogen at $z=9.16$ from the LOFAR 3C196 field
• Impact of the Epoch of Reionization sources on the 21-cm bispectrum
• The Evolution of Lyman Alpha Emitter Line Widths from z=5.7 to z=6.6
• Subaru/HSC z-Broadband Excess Selection of Extreme Emission Line Galaxies at z<1
• Lyman-$\alpha$ Emitting Galaxies (LAEs) at Cosmic Dawn: Implications and Predictions
• Near-IR narrow-band imaging with CIRCE at the Gran Telescopio Canarias: Searching for Ly$\alpha$-emitters at $z\sim 9.3$
• From ANN to BNN: Inferring Reionization Parameters using Uncertainty-aware Emulators of 21-cm Summaries