An extended [CII] halo around a massive star-forming galaxy at z = 5.3

Abstract

High-redshift observations are often biased towards massive and bright galaxies that are not necessarily representative of the full population. In order to accurately study galaxy evolution and mass assembly at these redshifts, observations of ``normal'' main sequence galaxies are required. Here we present Atacama Large Millimeter/Submillimeter Array (ALMA) 0.3" resolution observations of the [CII] emission line at 158$\mu$m of HZ7, a main sequence galaxy at $z=5.25$. Comparing to archival rest-frame UV observations taken by the Hubble Space Telescope (HST), we find strong evidence of the existence of extended [CII] emission, which we estimate to be twice the size of the rest-frame UV emission, yielding one of the first high-redshift objects where a clear signature of a [CII] ``Halo'' has been detected to date. For a matched Sérsic profile with n = 1, we measured a [CII] effective radius of $0.50\pm 0.04$" (3.07$\pm 0.25$ kpc) and an average rest-frame UV effective radius of $0.2\pm 0.04$" ($1.48\pm 0.16$ kpc). The [CII] morphology and kinematics of the system suggest a merging event resulting in a non rotating disk system. This event could be responsible for the extended [CII] emission. Alternatively, some potential obscured emission could also explain the [CII] to UV size ratio. These results contribute to the growing consensus with respect to the existence of extended [CII] emission around galaxies.

8 pages, 6 figures. Accepted to be published in MNRAS

References in corpus (15)

• Cosmic Star Formation History
• The Cosmic Evolution Survey (COSMOS) -- Overview
• A Highly Consistent Framework for the Evolution of the Star-Forming "Main Sequence" from z~0-6
• Weak Gravitational Lensing with COSMOS: Galaxy Selection and Shape Measurements
• A massive proto-cluster of galaxies at a redshift of z {\approx} 5.3
• Reionization Era Bright Emission Line Survey: Selection and Characterization of Luminous Interstellar Medium Reservoirs in the z>6.5 Universe
• The ALPINE-ALMA [CII] survey: Star-formation-driven outflows and circumgalactic enrichment in the early Universe
• Galaxy Stellar Mass Functions from z~10 to z~6 using the Deepest Spitzer/IRAC Data: No Significant Evolution in the Stellar-to-Halo Mass Ratio of Galaxies in the First Gyr of Cosmic Time
• Discovery of a Very Bright Strongly-Lensed Galaxy Candidate at z ~ 7.6
• ALMA Observation of 158 micron [CII] Line and Dust Continuum of a z=7 Normally Star-forming Galaxy in the Epoch of Reionization
• A kiloparsec view of a typical star-forming galaxy when the Universe was ~1 Gyr old. Part I. Outflow, halo, and interstellar medium properties
• Dust Properties of [CII] Detected z $\sim$ 5.5 Galaxies: New HST/WFC3 Near-IR Observations
• The ALPINE-ALMA [CII] survey: The contribution of major mergers to the galaxy mass assembly at z~5
• Blue Rest-Frame UV-Optical Colors in z~8 Galaxies from GREATS: Very Young Stellar Populations at ~650 Myr of Cosmic Time
• Relations between mid-IR dust emission and UV extinction

Cited by in corpus (16)

• Star-formation driven outflows in local dwarf galaxies as revealed from [CII] observations by Herschel
• The ALMA-CRISTAL survey: Gas, dust, and stars in star-forming galaxies when the Universe was ~1 Gyr old I. Survey overview and case studies
• Multi-phase black-hole feedback and a bright [CII] halo in a Lo-BAL quasar at $z\sim 6.6$
• The ALMA-CRISTAL Survey: Spatial extent of [CII] line emission in star-forming galaxies at $z=4-6$
• The ALMA-CRISTAL survey. Discovery of a 15 kpc-long gas plume in a $z=4.54$ Lyman-$\alpha$ blob
• The ALMA-CRISTAL survey: Resolved kinematic studies of main sequence star-forming galaxies at 4<z<6
• Evidence of extended [CII] and dust emission in local dwarf galaxies
• Carbon envelopes around merging galaxies at z ~ 4.5
• Infrared fine-structure lines at high redshift
• HYACINTH: HYdrogen And Carbon chemistry in the INTerstellar medium in Hydro simulations
• The ALMA-CRISTAL survey: Extended [CII] emission in an interacting galaxy system at z ~ 5.5
• The [C II] line emission as an interstellar medium probe in the MARIGOLD galaxies
• CO spectra of the ISM in the Host Galaxies of the Most Luminous WISE-Selected AGNs
• The early Universe with JWST and ALMA
• Far-infrared lines hidden in archival deep multi-wavelength surveys: Limits on [CII]-158$\mu$m at $z\sim 0.3-2.9$
• Uncovering the absorbed atomic Universe with the [OI]63um line