The connection between galactic outflows and the escape of ionizing photons

Abstract

We analyze spectra of a gravitationally lensed galaxy, known as the Sunburst Arc, that is leaking ionizing photons, also known as the Lyman continuum (LyC). Magnification from gravitational lensing permits the galaxy to be spatially resolved into one region that leaks ionizing photons, and several that do not. Rest-frame ultraviolet and optical spectra from Magellan target ten different regions along the lensed Arc, including six multiple images of the LyC leaking region, as well as four regions that do not show LyC emission. The rest-frame optical spectra of the ionizing photon emitting regions reveal a blue-shifted ($\Delta V$=27 km s${}^{-1}$) broad emission component (FWHM=327 km s${}^{-1}$) comprising 55% of the total [OIII] line flux, in addition to a narrow component (FWHM = 112 km s${}^{-1}$), suggesting the presence of strong highly ionized gas outflows. This is consistent with the high-velocity ionized outflow inferred from the rest-frame UV spectra. In contrast, the broad emission component is less prominent in the non-leaking regions, comprising $\sim$26% of total [OIII] line flux. The high ionization absorption lines are prominent in both leaker and non-leaker but low ionization absorption lines are very weak in the leaker, suggesting that the line of sight gas is highly ionized in the leaker. Analyses of stellar wind features reveal that the stellar population of the LyC leaking regions is considerably younger ($\sim$3 Myr) than the non-leaking regions ($\sim$12 Myr), highlighting that stellar feedback from young stars may play an important role in ionizing photon escape.

Accepted for publication in ApJ

References in corpus (17)

• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• Ubiquitous outflows in DEEP2 spectra of star-forming galaxies at z=1.4
• The Effects of Stellar Rotation. II. A Comprehensive Set of Starburst99 Models
• Conditions for Reionizing the Universe with A Low Galaxy Ionizing Photon Escape Fraction
• The MOSDEF Survey: Mass, Metallicity, and Star-formation Rate at z~2.3
• A Local Clue to the Reionization of the Universe
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionisation
• The MagE Spectrograph
• The Low-Redshift Lyman Continuum Survey I: New, Diverse Local Lyman-Continuum Emitters
• Q1549-C25: A Clean Source of Lyman-Continuum Emission at $z=3.15$
• The Low-Redshift Lyman Continuum Survey II: New Insights into LyC Diagnostics
• Lyman continuum leakage from low-mass galaxies with Mstar < 1.E8 Msun
• The origin of the escape of Lyman alpha and ionizing photons in Lyman Continuum Emitters
• The Sunburst Arc: Direct Lyman α escape observed in the brightest known lensed galaxy
• Do galaxies that leak ionizing photons have extreme outflows?
• Strong Lyman continuum emitting galaxies show intense CIV 1550 emission
• The impact of Stellar feedback from velocity-dependent ionised gas maps. -- A MUSE view of Haro 11

Cited by in corpus (20)

• JWST/NIRCam Probes Young Star Clusters in the Reionization Era Sunrise Arc
• Nitrogen-enriched, highly-pressurized nebular clouds surrounding a super star cluster at cosmic noon
• Very massive stars and Nitrogen emitting galaxies
• Ubiquitous broad-line emission and the relation between ionized gas outflows and Lyman continuum escape in Green Pea galaxies
• Clues on the presence and segregation of very massive stars in the Sunburst Lyman-continuum cluster at z=2.37
• Ionized gas kinematics and chemical abundances of low-mass star-forming galaxies at $z\sim 3$
• The Cosmic Telescope that Lenses the Sunburst Arc, PSZ1 G311.65-18.48: Strong Gravitational Lensing model and Source Plane Analysis
• Anatomy of an ionized bubble: NIRCam grism spectroscopy of the $z=6.6$ double-peaked Lyman-$\alpha$ emitter COLA1 and its environment
• New Ionization Models and the Shocking Nitrogen Excess at z > 5
• Spectroscopy of CASSOWARY gravitationally-lensed galaxies in SDSS: characterisation of an extremely bright reionization-era analog at $z=1.42$
• Witnessing an extreme, highly efficient galaxy formation mode with resolved Ly$\alpha$ and LyC emission
• Low-redshift Lyman Continuum Survey: Radio continuum properties of low-$z$ Lyman continuum emitters
• Little impact of mergers and galaxy morphology on the production and escape of ionizing photons in the early Universe
• The Sunburst Arc with JWST: II. Observations of an Eta Carinae Analog at $z=2.37$
• Ionizing Radiation Escape from Low-Redshift Galaxies and Its Connection to Cosmic Reionization
• The impact of cosmic ray feedback during the epoch of reionisation
• Power-law Emission-line Wings and Radiation-Driven Superwinds in Local Lyman Continuum Emitters
• Unraveling the Lyman Continuum Emission of Ion3: Insights from HST multi-band imaging and X-Shooter spectroscopy
• Lyman Continuum escaping from in-situ formed stars in a tidal bridge at z = 3
• Intergalactic Medium Tomography with the Sunburst Arc