Double-Peaked Lyα Emission during Reionization Requires Nearby Voids and a Favorable Local Ionizing Background
Clicks: 3
ID: 325542
2026
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This
article has not been analysed, so there is no overall score —
reader engagement is measured and shown alongside.
Reader Engagement
Emerging Content
0.6
/100
3 views
2 readers
AI Quality Assessment
Not analyzed
Readership in this journal
EmergingRanked #222 of 908 articles by views in monthly notices of the royal astronomical society
Most read
Least read
Bar heights use a square-root scale. Only the 120 most-read articles are drawn; the journal has 908 in total.
Mint this article as an NFT
Not yet mintedCreate a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.
5
SUSD
one-off · no wallet required
Abstract
Abstract Several Lyman-alpha (Lyα) emitters deep into the reionization era exhibit double-peaked Lyα emission profiles, raising the question of how the intergalactic medium can transmit photons blueward of the Lyα resonance at such high redshifts. To investigate this, we compute Lyα transmission along sightlines originating from galaxies in the Cosmic Dawn III simulation and identify cases that closely reproduce the observed double-peaked emission. In these cases, the sightlines intersect highly underdense voids located a few comoving megaparsecs from the source galaxy. These voids allow photons emitted blueward of Lyα to redshift through resonance without scattering while traversing them. The low opacity arises because the neutral hydrogen density scales with the square of the underlying gas density under ionization equilibrium, making sufficiently underdense regions with ≲ 30 % of cosmic mean density highly transmissive. Such voids naturally occur in the fluctuating cosmic density field, even in the vicinity of galaxies, and can also be associated with transmissive spikes in the Lyα forest. We find that the global probability of observing double-peaked emission is ∼0.5 % during reionization at an 80 % global ionization fraction, while no cases are found at 60 % ionization. We also find that this probability depends sensitively on the local ionizing background intensity, increasing by a factor of ∼103 for a tenfold increase in intensity. Recent accretion episodes of supermassive black holes can further increase this probability. These results suggest that double-peaked Lyα emission in high-z galaxies can serve as a sensitive probe of the ionizing background during the late stages of cosmic reionization.
| Reference Key |
openalex_W7159099411
Use this key to autocite in the manuscript while using
SciMatic Manuscript Manager or Thesis Manager
|
|---|---|
| Authors | Hyunbae Park, Aaron Smith, Intae Jung, Hidenobu Yajima, Pierre Ocvirk, Joseph S. W. Lewis, Luke Conaboy, Paul R. Shapiro, Ilian T. Iliev, Kyungjin Ahn, Joohyun Lee, Jenny G. Sorce, Yohan Dubois, Dominique Aubert |
| Journal | monthly notices of the royal astronomical society |
| Year | 2026 |
| DOI |
10.1093/mnras/stag1454
|
| URL | |
| Keywords | Keywords not found |
Citations
No citations found. To add a citation, contact the admin at info@scimatic.org
Comments
No comments yet. Be the first to comment on this article.