Hubble imaging of the ionizing radiation from a star-forming galaxy at z=3.2 with fesc>50%

Abstract

Star-forming galaxies are considered to be the leading candidate sources that dominate the cosmic reionization at z>7, and the search for analogs at moderate redshift showing Lyman continuum (LyC) leakage is currently a active line of research. We have observed a star-forming galaxy at z=3.2 with Hubble/WFC3 in the F336W filter, corresponding to the 730-890A rest-frame, and detect LyC emission. This galaxy is very compact and also has large Oxygen ratio [OIII]5007/[OII]3727 (>=10). No nuclear activity is revealed from optical/near-infrared spectroscopy and deep multi-band photometry (including the 6Ms X-ray, Chandra). The measured escape fraction of ionizing radiation spans the range 50-100\%, depending on the IGM attenuation. The LyC emission is detected at S/N=10 with m(F336W)=27.57+/-0.11 and it is spatially unresolved, with effective radius R_e<200pc. Predictions from photoionization and radiative transfer models are in line with the properties reported here, indicating that stellar winds and supernova explosions in a nucleated star-forming region can blow cavities generating density-bounded conditions compatible with optically thin media. Irrespective to the nature of the ionizing radiation, spectral signatures of these sources over the entire electromagnetic spectrum are of central importance for their identification during the epoch of reionization, when the LyC is unobservable. Intriguingly, the Spitzer/IRAC photometric signature of intense rest-frame optical emissions ([OIII]+Hbeta) observed recently at z~7.5-8.5 is similar to what is observed in this galaxy. Only the James Webb Space Telescope will measure optical line ratios at z>7 allowing a direct comparison with lower redshift LyC emitters, as reported here.

6 pages, 5 figures, ApJ submitted (comments welcome)

References in corpus (49)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• Starburst99: Synthesis Models for Galaxies with Active Star Formation
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• Detailed Decomposition of Galaxy Images. II. Beyond Axisymmetric Models
• The Great Observatories Origins Deep Survey: Initial Results From Optical and Near-Infrared Imaging
• Radiative transfer in a clumpy universe: IV. New synthesis models of the cosmic UV/X-ray background
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• An updated analytic model for the attenuation by the intergalactic medium
• Reionization after Planck: The Derived Growth of the Cosmic Ionizing Emissivity now matches the Growth of the Galaxy UV Luminosity Density
• Bolometric luminosities and Eddington ratios of X-ray selected Active Galactic Nuclei in the XMM-COSMOS survey
• The Birth of a Galaxy - III. Propelling reionisation with the faintest galaxies
• Ionization State of Inter-Stellar Medium in Galaxies: Evolution, SFR-M_star-Z Dependence, and Ionizing Photon Escape
• On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
• Early star-forming galaxies and the reionization of the Universe
• Nuclear activity versus star formation: emission-line diagnostics at ultraviolet and optical wavelengths
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• Using Lyman-alpha to detect galaxies that leak Lyman continuum
• Lyman continuum leaking from the compact star-forming dwarf galaxy J0925+1403
• WFPC2 Observations of the Hubble Deep Field-South
• A Rapidly Star-forming Galaxy 700 Million Years After the Big Bang at z=7.51
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• The Origin and Optical Depth of Ionizing Radiation in the "Green Pea" Galaxies
• A new determination of the primordial He abundance using the HeI 10830A emission line: cosmological implications
• A Spectroscopic Redshift Measurement for a Luminous Lyman Break Galaxy at z=7.730 using Keck/MOSFIRE
• Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical Properties and Implications for Studies at z>7
• A Local Clue to the Reionization of the Universe
• An extreme [OIII] emitter at $z=3.2$: a low metallicity Lyman continuum source
• UVUDF: Ultraviolet Through Near-infrared Catalog and Photometric Redshifts of Galaxies in the Hubble Ultra Deep Field
• New Constraints on the Lyman Continuum Escape Fraction at z~1.3
• A Definitive Survey for Lyman Limit Systems at z~3.5 with the Sloan Digital Sky Survey
• A Refined Estimate of the Ionizing Emissivity from Galaxies at z~3: Spectroscopic Follow-up in the SSA22a Field
• A Deep HST Search for Escaping Lyman Continuum Flux at z~1.3: Evidence for an Evolving Ionizing Emissivity
• The Great Observatories Origins Deep Survey: Constraints on the Lyman Continuum Escape Fraction Distribution of Lyman--Break Galaxies at 3.4<z<4.5
• On The Detection Of Ionizing Radiation Arising From Star-Forming Galaxies At Redshift z ~ 3-4 : Looking For Analogs Of "Stellar Reionizers"
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• The Nature of Extreme Emission Line Galaxies at z=1-2: Kinematics and Metallicities from Near-Infrared Spectroscopy
• The Hawk-I UDS and GOODS Survey (HUGS): Survey design and deep K-band number counts
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• Contamination on Lyman continuum emission at z >= 3: implication on the ionising radiation evolution
• Quantifying Distributions of Lyman Continuum Escape Fraction
• Chandra counterparts of CANDELS GOODS-S sources
• Resolving Ionisation and Metallicity on Parsec Scales Across Mrk 71 with HST-WFC3

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