Pith. sign in

REVIEW 4 cited by

Large Lyman-alpha opacity fluctuations and low CMB tau in models of late reionization with large islands of neutral hydrogen extending to z<5.5

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 1809.06374 v2 pith:ECKUFFNZ submitted 2018-09-17 astro-ph.CO

Large Lyman-alpha opacity fluctuations and low CMB tau in models of late reionization with large islands of neutral hydrogen extending to z<5.5

classification astro-ph.CO
keywords largereionizationly-alphagalaxieslateneutralopacityrapid
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

High-redshift QSO spectra show large spatial fluctuations in the Ly-alpha opacity of the intergalactic medium on surprisingly large scales at z>~5.5. We present a radiative transfer simulation of cosmic reionization driven by galaxies that reproduces this large scatter and the rapid evolution of the Ly-alpha opacity distribution at 5<z<6. The simulation also reproduces the low Thomson scattering optical depth reported by the latest CMB measurement and is consistent with the observed short near-zones and strong red damping wings in the highest-redshift QSOs. It also matches the rapid disappearance of observed Ly-alpha emission by galaxies at z>~6. Reionization is complete at z=5.3 in our model, and 50% of the volume of the Universe is ionized at z=7. Agreement with the Ly-alpha forest data in such a late reionization model requires a rapid evolution of the ionizing emissivity of galaxies that peaks at z~6.8. The late end of reionization results in a large scatter in the photoionisation rate and the neutral hydrogen fraction at redshifts as low as z<~5.5 with large residual neutral 'islands' that can produce very long Gunn-Peterson troughs resembling those seen in the data.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 4 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. A self-consistent analytical model for both the photoionization rate and reionization history

    astro-ph.CO 2026-06 unverdicted novelty 7.0

    A new analytical formalism self-consistently predicts both the ionized fraction x_i(z) and photoionization rate Gamma_HI(z), achieving percent-level accuracy in x_i and 20-30% accuracy in Gamma_HI versus radiative tra...

  2. Nearest Neighbour-Based Statistics for 21cm-Galaxy Cross-Correlations in the Epoch of Reionization

    astro-ph.CO 2026-02 conditional novelty 7.0

    kNN CDF statistics detect 21cm-galaxy cross-correlations more effectively than two-point methods and distinguish reionization models at fixed ionized fraction even with noise and foregrounds.

  3. Constraints on Neutrino Physics from DESI DR2 BAO and DR1 Full Shape

    astro-ph.CO 2025-03 conditional novelty 5.0

    DESI DR2 BAO and full-shape data plus CMB yield ∑m_ν < 0.0642 eV (95% CL) under ΛCDM, in 3σ tension with oscillation lower limits, relaxed to <0.163 eV in w0waCDM.

  4. The Lumina Project: Intergalactic Clumping and Recombination Sinks

    astro-ph.GA 2026-06 unverdicted novelty 4.0

    Simulations show recombination-weighted clumping is systematically lower than density-based measures, density-only prescriptions overpredict rates by 1.29-1.84 depending on redshift, and a new phase-space clumping fac...