The Kinematics of Multiple-Peaked Ly-alpha Emission in Star-Forming Galaxies at z~2-3

Abstract

We present new results on the Ly-alpha emission-line kinematics of 18 z~2-3 star-forming galaxies with multiple-peaked Ly-alpha profiles. With our large spectroscopic database of UV-selected star-forming galaxies at these redshifts, we have determined that ~30% of such objects with detectable Ly-alpha emission display multiple-peaked emission profiles. These profiles provide additional constraints on the escape of Ly-alpha photons due to the rich velocity structure in the emergent line. Despite recent advances in modeling the escape of Ly-alpha from star-forming galaxies at high redshifts, comparisons between models and data are often missing crucial observational information. Using Keck II NIRSPEC spectra of H-alpha (z~2) and [OIII] 5007 (z~3), we have measured accurate systemic redshifts, rest-frame optical nebular velocity dispersions and emission-line fluxes for the objects in the sample. Accurate systemic redshifts allow us to translate the multiple-peaked Ly-alpha profiles into velocity space, revealing that the majority (11/18) display double-peaked emission straddling the velocity-field zeropoint with stronger red-side emission. We compare our data with the predictions of simple models for outflowing and infalling gas distributions around high-redshift galaxies. While popular "shell" models provide a qualitative match with many of the observations of Ly-alpha emission, we find that in detail there are important discrepancies between the models and data, as well as problems with applying the framework of an expanding thin shell of gas to explain high-redshift galaxy spectra. Our data highlight these inconsistencies, as well as illuminating critical elements for success in future models of outflow and infall in high-redshift galaxies. [Abridged]

18 pages, 12 figures, ApJ in press

References in corpus (12)

• Cold streams in early massive hot haloes as the main mode of galaxy formation
• The Stellar, Gas and Dynamical Masses of Star-Forming Galaxies at z~2
• 3D Lyman-alpha radiation transfer. I. Understanding Lyman-alpha line profile morphologies
• 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
• H-alpha Observations of a Large Sample of Galaxies at z~2: Implications for Star Formation in High Redshift Galaxies
• Metallicities and Physical Conditions in Star-forming Galaxies at z~1.0-1.5
• The Impact of The IGM on High-Redshift Lyman Alpha Emission Lines
• 3D Lyman-alpha radiation transfer. III. Constraints on gas and stellar properties of z~3 Lyman break galaxies (LBG) and implications for high-z LBGs and Lyman-alpha emitters(LAEs)
• Lyman alpha Radiative Transfer in Cosmological Simulations using Adaptive Mesh Refinement
• Lyman alpha emission in high-redshift galaxies
• 3D Lya radiation transfer. II. Fitting the Lyman break galaxy MS 1512-cB58 and implications for Lya emission in high-z starbursts
• Kinematics of Gas in Lyman Alpha Nebulae

Cited by in corpus (93)

• Using Lyman-alpha to detect galaxies that leak Lyman continuum
• Lyman Alpha Emitting Galaxies as a Probe of Reionization
• Ly$\alpha$ emission from Green Peas: the role of circumgalactic gas density, covering, and kinematics
• Lyman-alpha spectral properties of five newly discovered Lyman continuum emitters
• An extreme [OIII] emitter at $z=3.2$: a low metallicity Lyman continuum source
• 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
• What is the physical origin of strong Lya emission? II. Gas Kinematics and Distribution of Lya Emitters
• The Properties and Prevalence of Galactic Outflows at z = 1 in the Extended Groth Strip
• The LyA-LyC Connection: Evidence for an Enhanced Contribution of UV-faint Galaxies to Cosmic Reionization
• Lyman-alpha emission properties of simulated galaxies: interstellar medium structure and inclination effects
• The Lyman alpha Reference Sample: II. HST imaging results, integrated properties and trends
• A Window On The Earliest Star Formation: Extreme Photoionization Conditions of a High-Ionization, Low-Metallicity Lensed Galaxy at z~2
• Gravitationally Lensed Galaxies at 2<z<3.5: Direct Abundance Measurements of Lya Emitters
• Recovering the systemic redshift of galaxies from their Lyman-alpha line profile
• Line Transfer through Clumpy, Large-Scale Outflows: Lyman Alpha Absorption and Halos around Starforming Galaxies
• High-resolution spectroscopy of a young, low-metallicity optically-thin L=0.02L* star-forming galaxy at z=3.12
• The COS Legacy Archive Spectroscopy SurveY (CLASSY) Treasury Atlas
• Discovery of a compact gas-rich DLA galaxy at z = 2.2: evidences for a starburst-driven outflow
• A systematic study of Lyman-Alpha transfer through outflowing shells: Model parameter estimation
• A Close Comparison between Observed and Modeled Lyα Lines for z ~ 2.2 Lyman Alpha Emitters
• On the (non-)enhancement of the Lyman α equivalent width by a multiphase interstellar medium
• Beamed Lyman Alpha Emission through Outflow-Driven Cavities
• The CALYMHA survey: Ly$\alpha$ escape fraction and its dependence on galaxy properties at $z=2.23$
• Ly$\alpha$ Spectra from Multiphase Outflows, and their Connection to Shell Models
• A connection between extremely strong Damped Lyman-alpha Systems and Lyman-alpha Emitting Galaxies at small impact parameters
• An HST/WFC3-IR Morphological Survey of Galaxies at z = 1.5-3.6: II. The Relation between Morphology and Gas-Phase Kinematics
• Three Lyman-alpha emitting filaments converging to a massive galaxy group at z=2.91: discussing the case for cold gas infall
• MUSE integral-field spectroscopy towards the Frontier Fields Cluster Abell S1063: I. Data products and redshift identifications
• Peering through the holes: the far UV color of star-forming galaxies at z~3-4 and the escaping fraction of ionizing radiation
• A VLT/FORS2 view at $z\sim 6$: Lyman-$\alpha$ emitter fraction and galaxy physical properties at the edge of the epoch of cosmic reionization
• Lya escape from z~0.03 star-forming galaxies: the dominant role of outflows
• Puzzling Lyman-alpha line profiles in green pea galaxies
• The X-SHOOTER Lyman-$\alpha$ survey at z=2 (XLS-z2) I: What makes a galaxy a Lyman-$\alpha$ emitter?
• Ly$\alpha$-Lyman Continuum connection in 3.5 < z < 4.3 star-forming galaxies from the VUDS survey
• Feedback in low-mass galaxies in the early Universe
• From Mirrors to Windows: Lyman-Alpha Radiative Transfer in a Very Clumpy Medium
• The LyAlpha Line Profiles of Ultraluminous Infrared Galaxies: Fast Winds and Lyman Continuum Leakage
• An Ultraluminous Lyman Alpha Emitter with a Blue Wing at z=6.6
• The redshift evolution of rest-UV spectroscopic properties in Lyman Break Galaxies at z ~ 2-4
• Resonant line transfer in a fog: Using Lyman-alpha to probe tiny structures in atomic gas
• Can galactic outflows explain the properties of Ly-alpha emitters?
• A High Fraction of Ly-alpha-Emitters Among Galaxies with Extreme Emission Line Ratios at z ~ 2
• Three Lyman-alpha emitting galaxies within a quasar proximity zone at z=5.8
• Modeling $237$ Lyman-$\alpha$ spectra of the MUSE-Wide survey
• Complex Lyman Alpha Profiles in Redshift 6.6 Ultraluminous Lyman Alpha Emitters
• The UV, Lyman-alpha, and dark matter halo properties of high redshift galaxies
• The physics of Lyman-alpha escape from disc-like galaxies
• Constraints on the Lyman continuum escape fraction for faint star forming galaxies
• Illuminating gas in-/outflows in the MUSE deepest fields: discovery of Ly-alpha nebulae around forming galaxies at z~3.3
• Searching for Neutral Hydrogen Halos around z ~ 2.1 and z ~ 3.1 Ly-alpha Emitting Galaxies
• Spectroscopic Confirmation of an Ultra Massive and Compact Galaxy at z=3.35: A Detailed Look at an Early Progenitor of Local Most Massive Ellipticals
• Simulating the diversity of shapes of the Lyman-$\alpha$ line
• The Spectrally Resolved Lyman-alpha Emission of Three Lyman-alpha Selected Field Galaxies at z~2.4 from the HETDEX Pilot Survey
• HETDEX Public Source Catalog 1: 220K Sources Including Over 50K Lyman Alpha Emitters from an Untargeted Wide-area Spectroscopic Survey
• Equivalent widths of Lyman $\alpha$ emitters in MUSE-Wide and MUSE-Deep
• The Properties of Lyman Alpha Nebulae: Gas Kinematics from Non-resonant Lines
• The VANDELS survey: the role of ISM and galaxy physical properties on the escape of Lyα emission in z $\sim$ 3.5 star-forming galaxies
• The KBSS-KCWI Survey: The connection between extended Ly$\alpha$ halos and galaxy azimuthal angle at $z\sim 2-3$
• Stacked Rest-Frame UV Spectra of Ly$\alpha$-Emitting and Continuum-Selected Galaxies at 2<z<3.5
• Double-peaked Lyman-$\alpha$ emission at z=6.803: a reionisation-era galaxy self-ionising its local HII bubble
• Crucial Factors for Lyα Transmission in the Reionizing Intergalactic Medium: Infall Motion, HII Bubble Size, and Self-shielded Systems
• Confirmation of double peaked Lyman-alpha emission at z=6.593: Witnessing a galaxy directly contributing to the reionisation of the Universe
• Lyman Alpha and MgII as Probes of Galaxies and their Environments
• The Circumgalactic Medium of Extreme Emission Line Galaxies at z ~ 2: Resolved Spectroscopy and Radiative Transfer Modeling of Spatially Extended Lyman-alpha Emission in the KBSS-KCWI Survey
• The Evolution of the Ultraluminous Ly-alpha Luminosity Function over z=5.7-6.6
• Magellan/MMIRS near-infrared multi-object spectroscopy of nebular emission from star forming galaxies at 2<z<3
• Early Results from GLASS-JWST XXII: Rest frame UV-optical spectral properties of Lyman-alpha emitting galaxies at 3 $<$ z $<$ 6
• The interstellar medium and feedback in the progenitors of the compact passive galaxies at z~2
• Galactic winds and stellar populations in Lyman $\alpha$ emitting galaxies at z ~ 3.1
• Recovery and analysis of rest-frame UV emission lines in 2052 galaxies observed with MUSE at $1.5<z<6.4$
• Revisiting the Gas Kinematics in SSA22 Lyman-$\alpha$ Blob 1 with Radiative Transfer Modeling in a Multiphase, Clumpy Medium
• Probing High-Redshift Galaxy Formation at the Highest Luminosities: New Insights from DEIMOS Spectroscopy
• Lyα emitters in a cosmological volume I: the impact of radiative transfer
• The imprint of cosmic ray driven outflow on Lyman-alpha spectra
• Pinpointing the Molecular Gas within a Lyman Alpha Blob at z ~ 2.7
• Extended and Filamentary Lyman Alpha Emission from the Formation of a Protogalactic Halo at z=2.63
• Radiative Transfer Distortions of Lyman-$\alpha$ Emitters: a New Fingers-of-God Damping in the Clustering in Redshift Space
• Dust attenuation of the nebular regions and optical emission lines of $z\sim 2$ star-forming galaxies
• Galactic winds - How to launch galactic outflows in typical Lyman-break galaxies
• LESSER: A Catalogue of Spectroscopically selected sample of Lyman-$\alpha$ Emitters Lensed By Galaxies
• A Correlation Between Lyα Spectral Line Profile and Rest-Frame UV Morphology
• The Ly$\alpha$ emission from high-$z$ galaxies hosting strong Damped Ly$\alpha$ systems
• SHELLQs. Bridging the Gap: JWST Unveils Obscured Quasars in the Most Luminous Galaxies at z > 6
• A UV Ultra-luminous Lyman Break Galaxy at Z=2.78 in NDWFS Bootes Field
• Resolved galactic superwinds reconstructed around their host galaxies at z>3
• The MUSE Extremely Deep Field: Classifying the Spectral Shapes of Lya Emitting Galaxies
• Blue Wings and Bumps via Fermi-like Acceleration of Lyman-alpha photons across Shocks
• Spitzer's View of the Candidate Cluster and Protocluster Catalog (CCPC)
• The Evolution of Lyman Alpha Emitter Line Widths from z=5.7 to z=6.6
• A z ~ 5.7 Lyα Emission Line with an Ultra Broad Red Wing
• Design and construction progress of LRS2-B: a new low resolution integral field spectrograph for the Hobby-Eberly Telescope
• A unique window into the Epoch of Reionisation: A double-peaked Lyman-$\alpha$ emitter in the proximity zone of a quasar at $z\sim 6.6$