Green Pea Galaxies Reveal Secrets of Ly$\alpha$ Escape

Abstract

We analyze archival Ly$\alpha$ spectra of 12 "Green Pea" galaxies observed with the Hubble Space Telescope, model their Ly$\alpha$ profiles with radiative transfer models, and explore the dependence of Ly$\alpha$ escape fraction on various properties. Green Pea galaxies are nearby compact starburst galaxies with [OIII]$\lambda$5007 equivalent widths of hundreds of Å. All 12 Green Pea galaxies in our sample show Ly$\alpha$ lines in emission, with a Ly$\alpha$ equivalent width distribution similar to high redshift Ly$\alpha$ emitters. Combining the optical and UV spectra of Green Pea galaxies, we estimate their Ly$\alpha$ escape fractions and find correlations between Ly$\alpha$ escape fraction and kinematic features of Ly$\alpha$ profiles. The escape fraction of Ly$\alpha$ in these galaxies ranges from 1.4% to 67%. We also find that the Ly$\alpha$ escape fraction depends strongly on metallicity and moderately on dust extinction. We compare their high-quality Ly$\alpha$ profiles with single HI shell radiative transfer models and find that the Ly$\alpha$ escape fraction anti-correlates with the derived HI column densities. Single shell models fit most Ly$\alpha$ profiles well, but not the ones with highest escape fractions of Ly$\alpha$. Our results suggest that low HI column density and low metallicity are essential for Ly$\alpha$ escape, and make a galaxy a Ly$\alpha$ emitter.

arXiv comment9 figures, ApJ accepted

References in corpus (73)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• Correcting for the Effects of Interstellar Extinction
• Rest-Frame Ultraviolet Spectra of z~3 Lyman Break Galaxies
• The Structure and Kinematics of the Circum-Galactic Medium from Far-UV Spectra of z~2-3 Galaxies
• Statistics of 207 Lya Emitters at a Redshift Near 7: Constraints on Reionization and Galaxy Formation Models
• Galaxy Zoo Green Peas: Discovery of A Class of Compact Extremely Star-Forming Galaxies
• 3D Lyman-alpha radiation transfer. I. Understanding Lyman-alpha line profile morphologies
• Luminosity functions of Lyman-alpha emitters at z=6.5, and z=5.7: evidence against reionization at z=6
• Ly Alpha-Emitting Galaxies at z=3.1: L* Progenitors Experiencing Rapid Star Formation
• Lyman Alpha Radiation From Collapsing Protogalaxies I: Characteristics of the Emergent Spectrum
• Using Lyman-alpha to detect galaxies that leak Lyman continuum
• The Density of Lyman-alpha Emitters at Very High Redshift
• Extreme Feedback and the Epoch of Reionization: Clues in the Local Universe
• New observations of z~7 galaxies: evidence for a patchy reionization
• Keck Spectroscopy of Faint 3<z<7 Lyman Break Galaxies:- II. A High Fraction of Line Emitters at Redshift Six
• First Results from the Large Area Lyman Alpha Survey
• Subaru Deep Survey II. Luminosity Functions and Clustering Properties of Lya Emitters at z=4.86 in the Subaru Deep Field
• Ly$\alpha$ emission from Green Peas: the role of circumgalactic gas density, covering, and kinematics
• Green Pea Galaxies and cohorts: Luminous Compact Emission-Line Galaxies in the Sloan Digital Sky Survey
• Completing the Census of Ly-alpha Emitters at the Reionization Epoch
• Spectroscopic Confirmation of Three Redshift 5.7 Lyman-alpha Emitters from the Large Area Lyman Alpha Survey
• An Atlas of z=5.7 and z=6.5 Ly alpha Emitters
• Lyman-Alpha-Emitting Galaxies at z = 2.1 in ECDF-S: Building Blocks of Typical Present-day Galaxies?
• The Physical Nature of Lyman Alpha Emitting Galaxies at z=3.1
• Rapid Decline of Lyman-alpha Emission Toward the Reionization Era
• The Ly-alpha Properties of Faint Galaxies at z2-3 with Systemic Redshifts and Velocity Dispersions from Keck-MOSFIRE
• What is the physical origin of strong Lya emission? II. Gas Kinematics and Distribution of Lya Emitters
• A Galaxy at z=5.34
• The First Systematic Survey for Lyman Alpha Emitters at z=7.3 with Red-sensitive Subaru/Suprime-Cam
• Optical to mid-IR observations of Lyman-alpha galaxies at redshift 5 in the HUDF: a young and low mass population
• The Lyman alpha Reference Sample: II. HST imaging results, integrated properties and trends
• The Lyman alpha morphology of local starburst galaxies: release of calibrated images
• Lyman alpha emission in starbursts: implications for galaxies at high redshift
• The Lyman-alpha Reference Sample: I. Survey outline and first results for Markarian 259
• Average Metallicity and Star Formation Rate of Lya Emitters Probed by a Triple Narrow-Band Survey
• Gas Motion Study of Lya Emitters at z~2 Using UV and Optical Spectral Lines
• The Lyman Alpha Reference Sample: V. The impact of neutral ISM kinematics and geometry on Lyman Alpha escape
• On the Detectability of Lyman-alpha Emission in Star-forming Galaxies: The Role of Dust
• An Ultraviolet Spectroscopic Atlas of Local Starbursts and Star-Forming Galaxies: The Legacy of FOS and GHRS
• Effects of Dust Geometry in Lyman Alpha Galaxies at z = 4.4
• First spectroscopic measurements of [OIII] emission from Lyman-alpha selected field galaxies at z ~ 3.1
• A Close Comparison between Observed and Modeled Lyα Lines for z ~ 2.2 Lyman Alpha Emitters
• A systematic study of Lyman-Alpha transfer through outflowing shells: Model parameter estimation
• The effect of dust geometry on the Lyman-alpha output of galaxies
• The HETDEX Pilot Survey V: The Physical Origin of Lyman-alpha Emitters Probed by Near-infrared Spectroscopy
• Lyman alpha emitting galaxies at 0.2 < z < 0.35 from GALEX spectroscopy
• Grid of Lya radiation transfer models for the interpretation of distant galaxies
• Inferences on the distribution of Ly-alpha emission of z~7 and z~8 galaxies
• Lyman Alpha Emitters at z=7 in the Subaru/XMM-Newton Deep Survey Field: Photometric Candidates and Luminosity Function
• Linking Ly-alpha and Low-Ionization Transitions at Low Optical Depth
• The physical properties of Lyalpha emitting galaxies: not just primeval galaxies?
• Sizing up Lyman-alpha and Lyman Break Galaxies
• Lya escape from z~0.03 star-forming galaxies: the dominant role of outflows
• "Direct" Gas-phase Metallicities, Stellar Properties, and Local Environments of Emission-line Galaxies at Redshift below 0.90
• Ly alpha emitting galaxies as early stages in galaxy formation
• HST/ACS Lyman alpha imaging of the nearby starburst ESO338-IG04
• Lyman alpha line formation in starbursting galaxies I. Moderately thick, dustless, and static HI media
• Investigating Nearby Star-Forming Galaxies in the Ultraviolet with HST/COS Spectroscopy. I: Spectral Analysis and Interstellar Abundance Determinations
• On the influence of physical galaxy properties on Lyman-alpha escape in star-forming galaxies
• Evolution of the observed Ly-alpha luminosity function from z = 6.5 to z = 7.7: evidence for the epoch of reionization ?
• The Spectrally Resolved Lyman-alpha Emission of Three Lyman-alpha Selected Field Galaxies at z~2.4 from the HETDEX Pilot Survey
• Dust Extinction and Metallicities of Star-Forming Lyman Alpha Emitting Galaxies at Low Redshift
• A 10 deg${}^2$ Lyman-$\alpha$ survey at z=8.8 with spectroscopic follow-up: strong constraints on the LF and implications for other surveys
• The Lyman Alpha Reference Sample: III. Properties of the Neutral ISM from GBT and VLA Observations
• Evidence for Spatially Compact Lyman Alpha Emission in z=3.1 Lyman-Alpha-Emitting Galaxies
• Lyman alpha Luminosity Functions at Redshift z = 4.5
• A Plethora of AGN Among Lyman Alpha Galaxies at Low Redshift
• Cosmic Origins Spectrograph Observations of the Chemical Composition of LMC N132D
• Metallicities of Emission-Line Galaxies from HST ACS PEARS and HST WFC3 ERS Grism Spectroscopy at 0.6 < z < 2.4
• On The Origin of Lyman-alpha Absorption in Nearby Starbursts and Implications for Other Galaxies
• Galactic winds and stellar populations in Lyman $\alpha$ emitting galaxies at z ~ 3.1
• X-ray Constraints on the Lyman-Alpha Escape Fraction

Cited by in corpus (75)

• The Universe is Reionizing at z~7: Bayesian Inference of the IGM Neutral Fraction Using Ly$\alpha$ Emission from Galaxies
• Detection of high Lyman continuum leakage from four low-redshift compact star-forming galaxies
• Inferences on the Timeline of Reionization at z~8 From the KMOS Lens-Amplified Spectroscopic Survey
• Lyman-alpha spectral properties of five newly discovered Lyman continuum emitters
• Ly$\alpha$ profile, dust, and prediction of Ly$\alpha$ escape fraction in Green Pea Galaxies
• Direct Lyman continuum and Lyman-alpha escape observed at redshift 4
• The LyA-LyC Connection: Evidence for an Enhanced Contribution of UV-faint Galaxies to Cosmic Reionization
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization III. the Ly$\alpha$ Equivalent-width Distribution and Ionized Structures at $z>7$
• Blueberry galaxies: the lowest mass young starbursts
• SILVERRUSH. V. Census of Lya, [OIII]5007, Ha, and [CII]158um Line Emission with ~1000 LAEs at z=4.9-7.0 Revealed with Subaru/HSC
• Recovering the systemic redshift of galaxies from their Lyman-alpha line profile
• Understanding the escape of LyC and Ly$\alpha$ photons from turbulent clouds
• Lyman Radiation Hydrodynamics of Turbulent H II Regions in Molecular Clouds: A Physical Origin of LyC Leakage and the Associated Ly$\alpha$ Spectra
• The CALYMHA survey: Lya luminosity function and global escape fraction of Lya photons at z=2.23
• The THESAN project: Lyman-alpha emission and transmission during the Epoch of Reionization
• The Recent Burstiness of Star Formation in Galaxies at z~4.5 from H$\alpha$ Measurements
• Finding Peas in the Early Universe with JWST
• Three Lyman-alpha emitting filaments converging to a massive galaxy group at z=2.91: discussing the case for cold gas infall
• Measuring the properties of reionised bubbles with resolved Lyman alpha spectra
• The MUSE Hubble Ultra Deep Field Survey XIII. Spatially resolved spectral properties of Lyman alpha haloes around star-forming galaxies at z > 3
• Puzzling Lyman-alpha line profiles in green pea galaxies
• From Mirrors to Windows: Lyman-Alpha Radiative Transfer in a Very Clumpy Medium
• Resonant line transfer in a fog: Using Lyman-alpha to probe tiny structures in atomic gas
• On the UV compactness and morphologies of typical Lyman-a emitters from z~2 to z~6
• Modeling $237$ Lyman-$\alpha$ spectra of the MUSE-Wide survey
• On the Lack of Correlation Between [OIII]/[OII] and Lyman-Continuum Escape Fraction
• Lyman-alpha emitters gone missing: the different evolution of the bright and faint populations
• Modelling the observed luminosity function and clustering evolution of Lyman-$\alpha$ emitters: growing evidence for late reionization
• AGN-driven outflows and the formation of Ly$\alpha$ nebulae around high-z quasars
• Lyman Alpha Signatures from Direct Collapse Black Holes
• Evidence for a direct collapse black hole in the Lyman-alpha source CR7
• A systematic study of the escape of LyC and Ly$\alpha$ photons from star-forming, magnetized turbulent clouds
• Equivalent widths of Lyman $\alpha$ emitters in MUSE-Wide and MUSE-Deep
• Assessing the sources of reionisation: a spectroscopic case study of a 30$\times$ lensed galaxy at $z\sim 5$ with Lyα, CIV, MgII, and [NeIII]
• Direct T${}_e$ metallicity calibration of R23 in strong line emitters
• Crucial Factors for Lyα Transmission in the Reionizing Intergalactic Medium: Infall Motion, HII Bubble Size, and Self-shielded Systems
• Lyman-alpha transmission properties of the intergalactic medium in the CoDaII simulation
• The Lensed Lyman-Alpha MUSE Arcs Sample (LLAMAS) : I. Characterisation of extended Lyman-alpha haloes and spatial offsets
• Stars and gas in the most metal-poor galaxies I: COS and MUSE observations of SBS 0335-052E
• Ly$\alpha$ and UV Sizes of Green Pea Galaxies
• Lyman-Alpha Emitter Galaxies at z ~ 2.8 in the Extended Chandra Deep Field-South: I. Tracing the Large-Scale Structure via Lyman-Alpha Imaging
• About AGN ionization echoes, thermal echoes, and ionization deficits in low redshift Lyman-alpha blobs
• The Compact UV Size of Green Pea Galaxies As Local Analogs of High-redshift Ly$\alpha$-Emitters
• Variations of Observed Lyman-α Spectra Shapes due to the Intergalactic Absorption
• The VIMOS Ultra Deep Survey: The role of HI kinematics and HI column density on the escape of Lyalpha photons in star-forming galaxies at 2<z<4
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization II. The Deepest Near-Infrared Spectroscopic Observation at $z\gtrsim 7$
• The Importance Of Star Formation Intensity In LYα Escape From Green Pea Galaxies And Lyman Break Galaxy Analogs
• Revisiting the Gas Kinematics in SSA22 Lyman-$\alpha$ Blob 1 with Radiative Transfer Modeling in a Multiphase, Clumpy Medium
• Lyman-alpha radiative transfer: Modeling spectrum and surface brightness profile of Lyman-alpha emitting galaxies at z=3-6
• Properties and redshift evolution of star-forming galaxies with high [OIII]/[OII] ratios with MUSE at 0.28<z<0.85
• The Effect of Bi-conical Outflows on Ly$\alpha$ Escape From Green Peas
• The imprint of cosmic ray driven outflow on Lyman-alpha spectra
• Ly-alpha emission in low-redshift most metal-deficient compact star-forming galaxies
• The Atomic Gas Mass of Green Pea Galaxies
• The THESAN project: Lyman-alpha emitter luminosity function calibration
• Ly-alpha Radiative Transfer: A Stokes Vector Approach to Ly-alpha Polarization
• Median Surface Brightness Profiles of Lyman-$\alpha$ Haloes in the MUSE Extremely Deep Field
• SN 2021adxl: A luminous nearby interacting supernova in an extremely low metallicity environment
• Characterisation of the stellar content of SDSS EELGs through self-consistent spectral modelling
• A Green Pea starburst arising from a galaxy-galaxy merger
• Stellar feedback in a clumpy galaxy at $z\sim$ 3.4
• Crossing walls and windows: the curious escape of Lyman-$\alpha$ photons through ionised channels
• NuSTAR hard X-ray data and Gemini 3D spectra reveal powerful AGN and outflow histories in two low-redshift Lyman-$\alpha$ blobs
• HI Imaging of a Blueberry Galaxy Suggests a Merger Origin
• A MUSE/VLT spatially resolved study of the emission structure of Green Pea galaxies
• A NuSTAR and XMM-Newton Study of the Two Most Actively Star-forming Green Pea Galaxies (SDSS J0749+3337 and SDSS J0822+2241)
• The MUSE Extremely Deep Field: Classifying the Spectral Shapes of Lya Emitting Galaxies
• Ionized gas metallicity of the strong [OIII]λ emission-line compact galaxies in the LAMOST survey
• Low-metallicity massive single stars with rotation. III. Source of ionization and C-IV emission in I Zw 18
• Scattering of Lyα Photons through the Reionizing Intergalactic Medium: I. Spectral Energy Distribution
• The HI gas fraction scaling relation of the Green Pea galaxies
• A resolved Lyman-Alpha profile with doubly peaked emission at z~7
• Double-Peaked Ly$\alpha$ Emission during Reionization Requires Nearby Voids and a Favorable Local Ionizing Background
• Unveiling an old disk around a massive young leaking blueberry in SDSS-IV MaNGA
• Constraining the geometry of the gas surrounding a typical galaxy at $z=3.4$ with Ly$\alpha$ polarization