Towards Reconciling Reionization with JWST: The Role of Bright Galaxies and Strong Feedback

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Bera, Ankita, Hassan, Sultan, Feldmann, Robert, Davé, Romeel, Finlator, Kristian
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913041324441600
author Bera, Ankita
Hassan, Sultan
Feldmann, Robert
Davé, Romeel
Finlator, Kristian
author_facet Bera, Ankita
Hassan, Sultan
Feldmann, Robert
Davé, Romeel
Finlator, Kristian
contents The elevated UV luminosity functions (UVLF) from recent James Webb Space Telescope (JWST) have challenged the viability of existing theoretical models. To address this, we use a semi-analytical framework -- which couples a physically motivated source model derived from radiative-transfer hydrodynamic simulations of reionization with a Markov Chain Monte Carlo sampler -- to perform a joint calibration to JWST galaxy surveys (UVLF, $ϕ_{\rm UV}$ and UV luminosity density, $ρ_{\rm UV}$) and reionization-era observables (ionizing emissivity, $\dot{N}_{\rm ion}$, neutral hydrogen fraction, $x_{\rm HI}$, and Thomson optical depth, $τ$). We find that models with weak feedback and a higher contribution from faint galaxies reproduce the reionization observables but struggle to match the elevated JWST UVLF at $z > 9$. In contrast, models with stronger feedback (i.e., rapid redshift evolution) and a higher contribution from bright galaxies successfully reproduce JWST UVLF at $z \geq 10$, but over-estimate the bright end at $z < 9$. The strong-feedback model constrained by JWST UVLF predicts a more gradual and extended reionization history, as opposed to the sudden reionization seen in the weak-feedback models. This extended nature of reionization ($z\sim 16$ - $6$) yields an optical depth consistent (at 2-$σ$) with the Cosmic Microwave Background (CMB) constraint, thereby alleviating the photon-budget crisis. In both scenarios, reionization is complete by $z \sim 6$, consistent with current data. Our analysis highlights the importance of accurately modeling feedback and ionizing emissivities from different source populations during the first billion years after the Big Bang.
format Preprint
id arxiv_https___arxiv_org_abs_2511_19600
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Towards Reconciling Reionization with JWST: The Role of Bright Galaxies and Strong Feedback
Bera, Ankita
Hassan, Sultan
Feldmann, Robert
Davé, Romeel
Finlator, Kristian
Cosmology and Nongalactic Astrophysics
Astrophysics of Galaxies
The elevated UV luminosity functions (UVLF) from recent James Webb Space Telescope (JWST) have challenged the viability of existing theoretical models. To address this, we use a semi-analytical framework -- which couples a physically motivated source model derived from radiative-transfer hydrodynamic simulations of reionization with a Markov Chain Monte Carlo sampler -- to perform a joint calibration to JWST galaxy surveys (UVLF, $ϕ_{\rm UV}$ and UV luminosity density, $ρ_{\rm UV}$) and reionization-era observables (ionizing emissivity, $\dot{N}_{\rm ion}$, neutral hydrogen fraction, $x_{\rm HI}$, and Thomson optical depth, $τ$). We find that models with weak feedback and a higher contribution from faint galaxies reproduce the reionization observables but struggle to match the elevated JWST UVLF at $z > 9$. In contrast, models with stronger feedback (i.e., rapid redshift evolution) and a higher contribution from bright galaxies successfully reproduce JWST UVLF at $z \geq 10$, but over-estimate the bright end at $z < 9$. The strong-feedback model constrained by JWST UVLF predicts a more gradual and extended reionization history, as opposed to the sudden reionization seen in the weak-feedback models. This extended nature of reionization ($z\sim 16$ - $6$) yields an optical depth consistent (at 2-$σ$) with the Cosmic Microwave Background (CMB) constraint, thereby alleviating the photon-budget crisis. In both scenarios, reionization is complete by $z \sim 6$, consistent with current data. Our analysis highlights the importance of accurately modeling feedback and ionizing emissivities from different source populations during the first billion years after the Big Bang.
title Towards Reconciling Reionization with JWST: The Role of Bright Galaxies and Strong Feedback
topic Cosmology and Nongalactic Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2511.19600