Did Globular Clusters Reionize the Universe?

Abstract

A problem still unsolved in cosmology is the identification of the sources of radiation able to reionize HI in the intergalactic medium (IGM) by z~6. Theoretical works and observations seem to indicate that the fraction, f_esc, of HI ionizing radiation emitted from galaxies that escapes into the IGM is small in the local universe (f_esc < 10%). At high redshift galaxies are more compact and probably gas rich implying smaller values of f_esc from their disks or spheroids. But if the sites of star formation are displaced from the disk or spheroid and the star formation efficiency of the proto-clusters is high, then f_esc should be about one. This star formation scenario is consistent with several models for globular clusters formation. Using simple arguments based on the observed number of globular cluster systems in the local universe and assuming that the oldest globular clusters formed before reionization and had f_esc~1, I show that they produced enough ionizing photons to reionize the IGM at z=6.

Accepted for publication in MNRAS letters. 5 pages, including 2 figures and 1 table

References in corpus (5)

• A Redshift z = 6.56 Galaxy Behind the Cluster Abell 370
• The baryon content of the Universe
• Approaching Reionization: The Evolution of the Lyman Alpha Forest from Redshifts Four to Six
• A Low Upper Limit to the Lyman Continuum Emission of two galaxies at z 3
• Lyman Break Galaxies and the Reionization of the Intergalactic Medium

Cited by in corpus (65)

• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• Extragalactic Globular Clusters and Galaxy Formation
• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• The First Cosmic Structures and their Effects
• X-ray Preionisation Powered by Accretion on the First Black Holes. I: a Model for the WMAP Polarisation Measurement
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionisation
• The White Dwarf Cooling Sequence of NGC6397
• Paving the way for the JWST: witnessing globular cluster formation at z>3
• A Deep HST Search for Escaping Lyman Continuum Flux at z~1.3: Evidence for an Evolving Ionizing Emissivity
• Simulating IGM Reionization
• Star clusters near and far; tracing star formation across cosmic time
• Interpreting ALMA Observations of the ISM During the Epoch of Reionisation
• Star formation at the smallest scales; A JWST study of the clump populations in SMACS0723
• A new perspective on globular clusters, their initial mass function, and their contribution to the stellar halo and to cosmic reionisation
• Massive Star cluster formation under the microscope at z=6
• Ionising the Intergalactic Medium by Star Clusters: The first empirical evidence
• Narrowband Lyman-Continuum Imaging of Galaxies at z ~ 2.85
• A Common Origin for Globular Clusters and Ultra-faint Dwarfs in Simulations of the First Galaxies
• The MUSE Deep Lensed Field on the Hubble Frontier Field MACS~J0416
• The Globular Cluster - Dark Matter Halo Connection
• Cosmic Star Formation, Reionization, and Constraints on Global Chemical Evolution
• Globular Cluster Formation Within The Aquarius Simulation
• Simulating Star Clusters Across Cosmic Time: I. Initial Mass Function, Star Formation Rates and Efficiencies
• Two Epochs of Globular Cluster Formation from Deep Fields Luminosity Functions: Implications for Reionization and the Milky Way Satellites
• The Little Engines That Could? Globular Clusters Contribute Significantly to Reionization-era Star Formation
• Runaway Stars and the Escape of Ionizing Radiation from High-Redshift Galaxies
• Globular Clusters as Tracers of Stellar Bimodality in Elliptical Galaxies: The Case of NGC 1399
• Clues on the Missing Sources of Reionization from Self-consistent Modeling of Milky Way and Dwarf Galaxy Globular Clusters
• Uncertain Times: The Redshift-Time Relation from Cosmology and Stars
• New Methods for Identifying Lyman Continuum Leakers and Reionization-Epoch Analogues
• Multiple stellar populations and their evolution in globular clusters: A nucleosynthesis perspective
• Primordial Globular Clusters, X-Ray Binaries & Cosmological Reionisation
• Searching for z ~ 6 Objects with the HST Advanced Camera for Surveys: Preliminary Analysis of a Deep Parallel Field
• Simulating Star Clusters Across Cosmic Time: II. Escape Fraction of Ionizing Photons from Molecular Clouds
• Feedback from High-Mass X-Ray Binaries on the High Redshift Intergalactic Medium : Model Spectra
• Hubble Space Telescope Wide Field Camera 3 Observations of Escaping Lyman Continuum Radiation from Galaxies and Weak AGN at Redshifts $z$$\simeq$2.3-4.1
• The Metallicity of Pre-Galactic Globular Clusters: Observational consequences of the first stars
• Constraints on the Cosmological Coupling of Black Holes from the Globular Cluster NGC 3201
• A Census of the LyC Photons that Form the UV Background During Reionization
• Anatomy of a z=6 Lyman-α emitter down to parsec scales: extreme UV slopes, metal-poor regions and possibly leaking star clusters
• Star Cluster Formation and Survival in the First Galaxies
• Tracing the Sources of Reionization in Cosmological Radiation Hydrodynamics Simulations
• Search Instructions for Globular Clusters in Formation at High Redshifts
• Constraints on the [CII] luminosity of a proto-globular cluster at z~6 obtained with ALMA
• Globular Clusters in High-Redshift Dwarf Galaxies: A Case Study from the Local Group
• Star Forming Galaxies at z~6 and Reionization
• The evolution of the UV luminosity function of globular clusters in the E-MOSAICS simulations
• Have we detected one of the sources responsible for an early reionisation of the Universe?
• Statistical Microlensing Toward Magnified High-Redshift Star Clusters
• Globular Clusters and Streaming Velocities: Testing the new formation channel in high-resolution cosmological simulations
• The First Billion Years Project: Finding Infant Globular Clusters at z=6
• An Observational Test for the Anthropic Origin of the Cosmological Constant
• Modeling Reionization in a Bursty Universe
• The contribution of globular clusters to cosmic reionization
• Formation of globular clusters induced by external ultraviolet radiation
• Distinguishing reionization models using the largest cluster statistics of the 21-cm maps
• The inhomogenous reionization of the inter-galactic medium by metal-poor globular clusters
• Ghostly Halos in Dwarf Galaxies: Constraints on the Star Formation Efficiency before Reionization
• Ghostly Stellar Haloes and their Relationship to Ultra-faint Dwarfs
• The Lost Dwarfs of Centaurus A and the Formation of its Dark Globular Clusters
• ARC: Adaptive Ray-tracing with CUDA, a New Ray Tracing Code for Parallel GPUs
• Interpreting the HI 21-cm cosmology maps through Largest Cluster Statistics -- I: Impact of the synthetic SKA1-Low observations
• Unveiling the Cosmic Gems Arc at $z\sim 10$ with JWST NIRCam
• Dynamical Simulations of the First Globular Clusters
• The Predicted Properties of Helium-Enriched Globular Cluster Progenitors at High Redshift