Galaxy Proximate Damped Lyman-Alpha Systems and HI Reionization Topology in TECHNICOLOR DAWN

Abstract

Recent observations from the James Webb Space Telescope (JWST) have revealed proximate damped Lyman-$\alpha$ systems (PDLAs) in the foreground of high redshift galaxies ($z>5$), which have been interpreted as neutral circumgalactic media (CGM). The ionization state of the CGM, potentially inferred from DLA strength, may serve as a probe to trace the progress of reionization, similarly to the ionization state of the intergalactic medium (IGM). To determine if this method has merit, we use the cosmological hydrodynamical simulation TECHNICOLOR DAWN to study simulated gas halos at redshifts $z=10,8,6,$ and $5.5$. We investigate the reionization topology to determine whether the CGM and IGM have similar ionization histories, and we study the relation between column density of neutral hydrogen (observationally measured by DLA strength), neutral fraction, and gas mass fraction of the foreground gas to determine whether PDLAs can be used to trace the progress of reionization. We find an inside-out-middle reionization topology, where the CGM reionizes after the IGM and remains partially neutral at $z=5.5$. The foreground column density of neutral hydrogen depends mostly on halo mass, with a weak dependence on neutral fraction or redshift. Therefore, provided precise estimates of halo or stellar mass, PDLAs may be used to trace the progress of reionization particularly at high redshifts.

arXiv comment12 Pages, 8 Figures; Published in ApJ

References in corpus (26)

• Planck 2015 results. XIII. Cosmological parameters
• The cosmological simulation code GADGET-2
• Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars
• Reionization of the Inhomogeneous Universe
• Reionization after Planck: The Derived Growth of the Cosmic Ionizing Emissivity now matches the Growth of the Galaxy UV Luminosity Density
• Evidence of patchy hydrogen reionization from an extreme Ly$\alpha$ trough below redshift six
• Reionization of the Intergalactic Medium and the Damping Wing of the Gunn-Peterson Trough
• Simulating Cosmic Reionization at Large Scales I: the Geometry of Reionization
• Hydrogen reionisation ends by $z=5.3$: Lyman-$\alpha$ optical depth measured by the XQR-30 sample
• Evidence of Gunn-Peterson damping wings in high-z quasar spectra: strengthening the case for incomplete reionization
• High Redshift Metals I.: The Decline of C IV at z > 5.3
• Metals in the IGM approaching the re-ionization epoch: results from X-shooter at the VLT
• Tracing the Reionization-Epoch Intergalactic Medium with Metal Absorption Lines
• The Local Group as a test of cosmological models
• The JWST-PRIMAL Legacy Survey. A JWST/NIRSpec reference sample for the physical properties and Lyman-$\alpha$ absorption and emission of $\sim 500$ galaxies at $z=5.5-13.4$
• JADES: Carbon enrichment 350 Myr after the Big Bang in a gas-rich galaxy
• The Evolution of O I over 3.2 < z < 6.5: Reionization of the Circumgalactic Medium
• SILVERRUSH. VI. A simulation of Ly$\alpha$ emitters in the reionization epoch and a comparison with Subaru Hyper Suprime-Cam survey early data
• Reionization in Technicolor
• The nature of proximate damped Lyman alpha systems
• The Topology of Cosmological Reionization
• The Late Reionization of Filaments
• The Faint Host Galaxies of C IV Absorbers at z > 5
• Evolution of Neutral Oxygen During the Epoch of Reionization and its Use in Estimating the Neutral Hydrogen Fraction
• Cosmic Variance and the Inhomogeneous UV Luminosity Function of Galaxies During Reionization
• All the Massive Galaxy Overdensities during Reionization: JWST Rest-Frame Optical Selection Reveals Young, Chemically Evolved Galaxies Embedded in Dense, Neutral Gas at z > 5