The impact of faint AGN discovered by JWST on reionization

Abstract

The relative contribution of emission from stellar sources and accretion onto supermassive black holes to reionization has been brought into focus again by the apparent high abundance of faint Active Galactic Nuclei (AGN) at $4\lesssim z\lesssim 11$ uncovered by JWST. We investigate here the contribution of these faint AGN to hydrogen and the early stages of helium reionization using the GPU-based radiative transfer code ATON-HE by post-processing a cosmological hydrodynamical simulation from the sherwood-relics suite of simulations. We study four models: two galaxy-only late-end reionization models, a QSO-assisted and a QSO-only model. In the QSO-assisted model, 1% of the haloes host AGN, with AGN luminosities scaled to contribute 17% of the total hydrogen-ionizing emissivity. In the QSO-only model, quasars account for all the hydrogen-ionizing emissivity, with 10% of the haloes hosting AGN. The SED of AGN is assumed to be a power-law with $\alpha =-1.7$ each with a 10 Myr lifetime. All models are calibrated to the observed mean Lyman-$\alpha$ forest transmission at $5\lesssim z\lesssim 6.2$. The QSO-assisted model requires an emissivity similar to the galaxy-only models and fits the observed distribution of the Lyman-$\alpha$ optical depths well. The QSO-only model is inconsistent with the observed Lyman-$\alpha$ optical depths distribution, and produces excessively high IGM temperatures at $z\lesssim 5$ due to an early onset of HeII reionization, unless the escape fraction of HeII-ionizing photons is assumed to be low. Our results suggest that a modest AGN contribution to reionization aligns with the Lyman-$\alpha$ forest data, whereas an AGN dominated scenario is difficult to reconcile.

19 pages, 11 figures

References in corpus (61)

• A luminous quasar at a redshift of z = 7.085
• Model-independent evidence in favor of an end to reionization by z~6
• A Luminous Quasar at Redshift 7.642
• New Determinations of the UV Luminosity Functions from z~9 to z~2 show a remarkable consistency with halo growth and a constant star formation efficiency
• The Pan-STARRS1 distant z>5.6 quasar survey: more than 100 quasars within the first Gyr of the universe
• A CEERS Discovery of an Accreting Supermassive Black Hole 570 Myr after the Big Bang: Identifying a Progenitor of Massive z > 6 Quasars
• Pōniuā'ena: A Luminous $z=7.5$ Quasar Hosting a 1.5 Billion Solar Mass Black Hole
• The Final SDSS High-Redshift Quasar Sample of 52 Quasars at z>5.7
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• Physical properties of 15 quasars at $z\gtrsim 6.5$
• Hydrogen reionisation ends by $z=5.3$: Lyman-$\alpha$ optical depth measured by the XQR-30 sample
• The first ultraviolet quasar stacked spectrum at z=2.4 from WFC3
• Four quasars above redshift 6 discovered by the Canada-France High-z Quasar Survey
• Inferences on the Timeline of Reionization at z~8 From the KMOS Lens-Amplified Spectroscopic Survey
• A Significantly Neutral Intergalactic Medium Around the Luminous z=7 Quasar J0252-0503
• The mean free path of ionizing photons at 5 < z < 6: evidence for rapid evolution near reionization
• A radiative transfer scheme for cosmological reionization based on a local Eddington tensor
• Probing the thermal state of the intergalactic medium at $z>5$ with the transmission spikes in high-resolution Ly$\alpha$ forest spectra
• Measurements of the z ~ 6 Intergalactic Medium Optical Depth and Transmission Spikes Using a New z > 6.3 Quasar Sample
• Voigt Profile Fitting to Quasar Absorption Lines: An Analytic Approximation to the Voigt-Hjerting Function
• Reionization and galaxy inference from the high-redshift Lyα forest
• JWST UNCOVER: Extremely red and compact object at$z_{\mathrm{phot}}\simeq 7.6$ triply imaged by Abell 2744
• A Candidate of a Least-Massive Black Hole at the First 1.1 Billion Years of the Universe
• Three new VHS-DES Quasars at 6.7 < z < 6.9 and Emission Line Properties at z > 6.5
• A consistent and robust measurement of the thermal state of the IGM at $2\le z\le 4$ from a large sample of Ly$\alpha$ forest spectra: Evidence for late and rapid HeII reionization
• LyC escape from SPHINX galaxies in the Epoch of Reionization
• The Obelisk simulation: galaxies contribute more than AGN to HI reionization of protoclusters
• Long Dark Gaps in the Ly$\beta$ Forest at $z<6$: Evidence of Ultra Late Reionization from XQR-30 Spectra
• (Nearly) Model-Independent Constraints on the Neutral Hydrogen Fraction in the Intergalactic Medium at $z\sim 5-7$ Using Dark Pixel Fractions in Ly$\alpha$ and Ly$\beta$ Forests
• Two bright z > 6 quasars from VST ATLAS and a new method of optical plus mid-infra-red colour selection
• XQR-30: the ultimate XSHOOTER quasar sample at the reionization epoch
• Unveiling Dark Matter free-streaming at the smallest scales with high redshift Lyman-alpha forest
• The Sherwood-Relics simulations: overview and impact of patchy reionization and pressure smoothing on the intergalactic medium
• Damping Wing-Like Features in the Stacked Ly$\alpha$ Forest: Potential Neutral Hydrogen Islands at $z<6$
• The Magellan M2FS Spectroscopic Survey of High-$z$ Galaxies: Lyα Emitters at $z\approx 6.6$ and the Evolution of Lyα Luminosity Function over $z\approx 5.7-6.6$
• A new bright z=6.82 quasar discovered with VISTA: VHS J0411-0907
• The Lyman Continuum Escape Fraction of Galaxies and AGN in the GOODS Fields
• The Lyman continuum escape fraction and the Mean Free Path of hydrogen ionizing photons for bright z~4 QSOs from SDSS DR14
• The need for obscured supermassive black hole growth to explain quasar proximity zones in the epoch of reionization
• Models of the Cosmological 21 cm Signal from the Epoch of Reionization Calibrated with Lyman-alpha and CMB Data
• UNCOVER: Candidate Red Active Galactic Nuclei at 3<z<7 with JWST and ALMA
• New Evidence for Extended HeII Reionization at z>3.5 from HeII Lyman Alpha and Beta Transmission Spikes
• The Rise of Faint, Red AGN at $z>4$: A Sample of Little Red Dots in the JWST Extragalactic Legacy Fields
• The Morphology of Reionization in a Dynamically Clumpy Universe
• Astraeus VI: Hierarchical assembly of AGN and their large-scale effect during the Epoch of Reionization
• UNCOVER: A NIRSpec Census of Lensed Galaxies at z=8.50-13.08 Probing a High AGN Fraction and Ionized Bubbles in the Shadow
• JWST Measurements of Neutral Hydrogen Fractions and Ionized Bubble Sizes at $z=7-12$ Obtained with Ly$\alpha$ Damping Wing Absorptions in 27 Bright Continuum Galaxies
• COSMOS-Web: The over-abundance and physical nature of "little red dots"--Implications for early galaxy and SMBH assembly
• Late-end reionization with ATON-HE: towards constraints from Lyman-$\alpha$ emitters observed with JWST
• Discovery of a very Lyman-$\alpha$-luminous quasar at z=6.62
• JWST PRIMER: A new multi-field determination of the evolving galaxy UV luminosity function at redshifts $\mathbf{z}\simeq 9-15$
• The Lyman-limit photon mean free path at the end of late reionisation in the Sherwood-Relics simulations
• Ly$\alpha$ Emission at $z=7-13$: Clear Ly$\alpha$ Equivalent Width Evolution Indicating the Late Cosmic Reionization History
• HeII Ly$\alpha$ Transmission Spikes and Absorption Troughs in Eight High-resolution Spectra Probing the End of HeII Reionization
• Ionising properties of galaxies in JADES for a stellar mass complete sample: resolving the cosmic ionising photon budget crisis at the Epoch of Reionisation
• Robustness of direct measurements of the mean free path of ionizing photons in the epoch of reionization
• Chasing the beginning of reionization in the JWST era
• The ionizing photon budget and effective clumping factor in radiative transfer simulations calibrated to Lyman-alpha forest data
• The Small Sizes and High Implied Densities of `Little Red Dots' with Balmer Breaks Could Explain Their Broad Emission Lines Without an AGN
• Cosmic Reionization in the JWST Era: Back to AGNs?
• What are the Pillars of Reionization? Revising the AGN Luminosity Function at z~5

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