Narrowband Lyman-Continuum Imaging of Galaxies at z ~ 2.85

Abstract

We present results from a survey for z~2.85 Lyman-Continuum (LyC) emission in the HS1549+1933 field and place constraints on the amount of ionizing radiation escaping from star-forming galaxies. Using a custom narrowband filter (NB3420) tuned to wavelengths just below the Lyman limit at z>=2.82, we probe the LyC spectral region of 49 Lyman break galaxies (LBGs) and 91 Lya-emitters (LAEs) spectroscopically confirmed at z>=2.82. Four LBGs and seven LAEs are detected in NB3420. Using V-band data probing the rest-frame non-ionizing UV, we observe that many NB3420-detected galaxies exhibit spatial offsets between their LyC and non-ionizing UV emission and are characterized by extremely blue NB3420-V colors, corresponding to low ratios of non-ionizing to ionizing radiation (F_UV/F_LyC) that are in tension with current stellar population synthesis models. We measure average values of F_UV/F_LyC for our LBG and LAE samples, correcting for foreground galaxy contamination and HI absorption in the IGM. We find (F_UV/F_LyC)_corr^LBG=82 +/- 45 and (F_UV/F_LyC)_corr^LAE=7.4 +/- 3.6. These flux-density ratios correspond respectively to relative LyC escape fractions of f_esc,rel^LBG=5-8% and f_esc,rel^LAE=18-49%, absolute LyC escape fractions of f_esc^LBG=1-2% and f_esc^LAE=5-15%, and a comoving LyC emissivity from star-forming galaxies of 8.8-15.0 x 10^24 ergs/s/Hz/Mpc^3. In order to study the differential properties of galaxies with and without LyC detections, we analyze narrowband Lya imaging and rest-frame near-infrared imaging, finding that while LAEs with LyC detections have lower Lya equivalent widths on average, there is no substantial difference in the rest-frame near-infrared colors of LBGs or LAEs with and without LyC detections. These preliminary results are consistent with an orientation-dependent model where LyC emission escapes through cleared paths in a patchy ISM.

31 pages, 14 figures, accepted by ApJ

References in corpus (12)

• An Observational Determination of the Bolometric Quasar Luminosity Function
• Multi-Wavelength Constraints on the Cosmic Star Formation History from Spectroscopy: the Rest-Frame UV, H-alpha, and Infrared Luminosity Functions at Redshifts 1.9<z<3.4
• The observed ionization rate of the intergalactic medium and the ionizing emissivity at z >5: Evidence for a photon starved and extended epoch of reionization
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• The Direct Detection of Lyman-Continuum Emission from Star-forming Galaxies at z~3
• A Spectroscopic Survey of Redshift 1.4<z<3.0 Galaxies in the Goods-North Field: Survey Description, Catalogs, and Properties
• Evolution of the Intergalactic Opacity: Implications for the Ionizing Background, Cosmic Star Formation, and Quasar Activity
• New Constraints on the Lyman Continuum Escape Fraction at z~1.3
• The Physical Nature of Rest-UV Galaxy Morphology During the Peak Epoch of Galaxy Formation
• The Column Density Distribution and Continuum Opacity of the Intergalactic and Circumgalactic Medium at Redshift <z>=2.4
• Feedback in the local LBG Analog Haro 11 as probed by far-UV and X-ray observations
• High-Redshift QSOs in the SWIRE Survey and the z~3 QSO Luminosity Function

Cited by in corpus (78)

• The Evolution of the Galaxy Rest-Frame Ultraviolet Luminosity Function Over the First Two Billion Years
• Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
• Reionization after Planck: The Derived Growth of the Cosmic Ionizing Emissivity now matches the Growth of the Galaxy UV Luminosity Density
• The Universe is Reionizing at z~7: Bayesian Inference of the IGM Neutral Fraction Using Ly$\alpha$ Emission from Galaxies
• Stellar Population Effects on the Inferred Photon Density at Reionization
• Cosmic Reionization after Planck: Could Quasars Do It All?
• Detection of high Lyman continuum leakage from four low-redshift compact star-forming galaxies
• The realm of the galaxy protoclusters
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• The Keck Lyman Continuum Spectroscopic Survey (KLCS): The Emergent Ionizing Spectrum of Galaxies at $z\sim 3$
• Using Lyman-alpha to detect galaxies that leak Lyman continuum
• The first ultraviolet quasar stacked spectrum at z=2.4 from WFC3
• Quasar Quartet Embedded in Giant Nebula Reveals Rare Massive Structure in Distant Universe
• J1154+2443: a low-redshift compact star-forming galaxy with a 46 per cent leakage of Lyman continuum photons
• Fluctuating feedback-regulated escape fraction of ionizing radiation in low-mass, high-redshift galaxies
• The First Billion Years Project: The escape fraction of ionizing photons in the epoch of reionization
• The Lyman-Continuum Photon Production Efficiency xi_{ion} of z~4-5 Galaxies from IRAC-based Halpha Measurements: Implications for the Escape Fraction and Cosmic Reionization
• A Local Clue to the Reionization of the Universe
• Hubble imaging of the ionizing radiation from a star-forming galaxy at z=3.2 with fesc>50%
• An extreme [OIII] emitter at $z=3.2$: a low metallicity Lyman continuum source
• The Lyman Continuum Escape Survey: Ionizing Radiation from [O III]-Strong Sources at a Redshift of 3.1
• The Ly-alpha Properties of Faint Galaxies at z2-3 with Systemic Redshifts and Velocity Dispersions from Keck-MOSFIRE
• The Spectroscopic Properties of Lyα-Emitters at z $\approx$ 2.7: Escaping Gas and Photons from Faint Galaxies
• Q1549-C25: A Clean Source of Lyman-Continuum Emission at $z=3.15$
• Reionization and high-redshift galaxies: the view from quasar absorption lines
• The Connection Between Reddening, Gas Covering Fraction, and the Escape of Ionizing Radiation at High Redshift
• A Deep Hubble and Keck Search for Definitive Identification of Lyman Continuum Emitters at z~3.1
• SILVERRUSH. VIII. Spectroscopic Identifications of Early Large Scale Structures with Protoclusters Over 200 Mpc at z~6-7: Strong Associations of Dusty Star-Forming Galaxies
• A Hard Ionizing Spectrum in z=3-4 Ly-alpha Emitters with Intense [OIII] Emission: Analogs of Galaxies in the Reionization Era?
• The Lyman Continuum escape fraction of galaxies at z=3.3 in the VUDS-LBC/COSMOS field
• A High-Resolution Hubble Space Telescope Study of Apparent Lyman Continuum Leakers at $z\sim 3$
• Indirect Evidence for Escaping Ionizing Photons in Local Lyman Break Galaxy Analogs
• The Lyman Continuum escape fraction of faint galaxies at z~3.3 in the CANDELS/GOODS-North, EGS, and COSMOS fields with LBC
• Peering through the holes: the far UV color of star-forming galaxies at z~3-4 and the escaping fraction of ionizing radiation
• Consequences of bursty star formation on galaxy observables at high redshifts
• The Metagalactic Ionizing Background: A Crisis in UV Photon Production or Incorrect Galaxy Escape Fractions?
• The fraction of ionizing radiation from massive stars that escapes to the intergalactic medium
• Ly$\alpha$-Lyman Continuum connection in 3.5 < z < 4.3 star-forming galaxies from the VUDS survey
• The Efficiency of Stellar Reionization: Effects of Rotation, Metallicity, and Initial Mass Function
• Feedback in low-mass galaxies in the early Universe
• The Lyman Continuum Escape Fraction of Low-Mass Star-Forming Galaxies at z~1
• The Role of Galaxies and AGN in Reionising the IGM - I: Keck Spectroscopy of 5 < z < 7 Galaxies in the QSO Field J1148+5251
• The contribution of faint AGNs to the ionizing background at z~4
• A physical model for the evolving UV luminosity function of high redshift galaxies and their contribution to the cosmic reionization
• The Lyman Continuum Escape Fraction of The Cosmic Horseshoe: A Test of Indirect Estimates
• Quantifying Distributions of Lyman Continuum Escape Fraction
• The contribution from stars stripped in binaries to cosmic reionization of hydrogen and helium
• No strong dependence of Lyman continuum leakage on physical properties of star-forming galaxies at $3.1\lesssim \mathbf{z}\lesssim 3.5$
• New constraints on the average escape fraction of Lyman continuum radiation in z~4 galaxies from the VIMOS Ultra Deep Survey (VUDS)
• Constraints on the Lyman continuum escape fraction for faint star forming galaxies
• The Lyman Continuum Escape Survey: Connecting Time-Dependent [OIII] and [OII] Line Emission with Lyman Continuum Escape Fraction in Simulations of Galaxy Formation
• The VANDELS survey: a measurement of the average Lyman-continuum escape fraction of star-forming galaxies at z=3.5
• Limits on the LyC signal from z~3 sources with secure redshift and HST coverage in the E-CDFS field
• Detection of hot, metal-enriched outflowing gas around $z\approx$2.3 star-forming galaxies in the Keck Baryonic Structure Survey
• Two sub-millimetre bright protoclusters bounding the epoch of peak star-formation activity
• Ly$\alpha$ view around a z=2.84 hyperluminous QSO at a node of the cosmic web
• Evidence of very low metallicity and high ionization state in a strongly lensed, star-forming dwarf galaxy at z=3.417
• On the AGN nature of two UV bright sources at z_spec~5.5 in the CANDELS fields: an update of the AGN space density at M1450~-22.5
• 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
• Searching for candidates of Lyman continuum sources - revisiting the SSA22 field
• The Epoch of Reionization in the R_h=ct Universe
• The source of leaking ionizing photons from Haro11 -- Clues from HST/COS spectroscopy of knots A, B and C
• On the origin of low escape fractions of ionizing radiation from massive star-forming galaxies at high redshift
• Characterizing the Star Formation of the Low-Mass SHIELD Galaxies from Hubble Space Telescope Imaging
• 3D-HST Emission Line Galaxies at z ~ 2: Discrepancies in the Optical/UV Star Formation Rates
• Lyman Continuum Galaxy Candidates in COSMOS
• Outside the Lyman-break box: detecting Lyman continuum emitters at $3.5<z<5.1$ with CLAUDS
• Upper limits on the escape fraction of ionizing radiation from galaxies at $2\lesssim z<6$
• The Lyman Continuum Escape Fraction of Star-forming Galaxies at $2.4\lesssim z\lesssim 3.0$ from UVCANDELS
• Ultra-deep Large Binocular Camera U-band Imaging of the GOODS-North Field: Depth vs. Resolution
• The Flatness and Sudden Evolution of the Intergalactic Ionizing Background
• Subaru narrow-band imaging search for Lyman continuum from galaxies at z>3 in the GOODS-N field
• High-Redshift Galaxy Surveys and the Reionization of the Universe
• Trident: A three-pronged galaxy survey. I. Lyman alpha emitting galaxies at z~2 in GOODS North
• Testing an indirect method for identifying galaxies with high levels of Lyman continuum leakage
• UV & Ly$\alpha$ halos of Ly$\alpha$ emitters across environments at z=2.84
• Physically motivated modeling of LyC escape fraction during reionization
• The Contribution of AGN Accretion Disks to Hydrogen Reionization