We present the physical extent of [C ii] 158 μm line-emitting gas from 46 star-forming galaxies at z = 4-6 from the ALMA Large Program to INvestigate C ii at Early Times (ALPINE). Using exponential profile fits, we measure the effective radius of the [C ii] line () for individual galaxies and compare them with the rest-frame ultraviolet (UV) continuum () from Hubble Space Telescope images. The effective radius exceeds by factors of ∼2-3, and the ratio of increases as a function of M star. We do not find strong evidence that the [C ii] line, rest-frame UV, and far-infrared (FIR) continuum are always displaced over ≃1 kpc scale from each other. We identify 30% of isolated ALPINE sources as having an extended [C ii] component over 10 kpc scales detected at 4.1σ-10.9σ beyond the size of rest-frame UV and FIR continuum. One object has tentative rotating features up to ∼10 kpc, where the 3D model fit shows the rotating [C ii]-gas disk spread over 4 times larger than the rest-frame UV-emitting region. Galaxies with the extended [C ii] line structure have high star formation rate, high stellar mass (M star), low Lyα equivalent width, and more blueshifted (redshifted) rest-frame UV metal absorption (Lyα line), as compared to galaxies without such extended [C ii] structures. Although we cannot rule out the possibility that a selection bias toward luminous objects may be responsible for such trends, the star-formation-driven outflow also explains all these trends. Deeper observations are essential to test whether the extended [C ii] line structures are ubiquitous to high-z star-forming galaxies.

The ALPINE-ALMA [C ii] Survey: Size of Individual Star-forming Galaxies at z = 4-6 and Their Extended Halo Structure

Vallini L.;Loiacono F.
Data Curation
;
Talia M.
Supervision
;
Bardelli S.;Vergani D.;Zucca E.;Cimatti A.
Supervision
2020

Abstract

We present the physical extent of [C ii] 158 μm line-emitting gas from 46 star-forming galaxies at z = 4-6 from the ALMA Large Program to INvestigate C ii at Early Times (ALPINE). Using exponential profile fits, we measure the effective radius of the [C ii] line () for individual galaxies and compare them with the rest-frame ultraviolet (UV) continuum () from Hubble Space Telescope images. The effective radius exceeds by factors of ∼2-3, and the ratio of increases as a function of M star. We do not find strong evidence that the [C ii] line, rest-frame UV, and far-infrared (FIR) continuum are always displaced over ≃1 kpc scale from each other. We identify 30% of isolated ALPINE sources as having an extended [C ii] component over 10 kpc scales detected at 4.1σ-10.9σ beyond the size of rest-frame UV and FIR continuum. One object has tentative rotating features up to ∼10 kpc, where the 3D model fit shows the rotating [C ii]-gas disk spread over 4 times larger than the rest-frame UV-emitting region. Galaxies with the extended [C ii] line structure have high star formation rate, high stellar mass (M star), low Lyα equivalent width, and more blueshifted (redshifted) rest-frame UV metal absorption (Lyα line), as compared to galaxies without such extended [C ii] structures. Although we cannot rule out the possibility that a selection bias toward luminous objects may be responsible for such trends, the star-formation-driven outflow also explains all these trends. Deeper observations are essential to test whether the extended [C ii] line structures are ubiquitous to high-z star-forming galaxies.
2020
Fujimoto S.; Silverman J.D.; Bethermin M.; Ginolfi M.; Jones G.C.; Le F vre O.; Dessauges-Zavadsky M.; Rujopakarn W.; Faisst A.L.; Fudamoto Y.; Cassata P.; Morselli L.; Maiolino R.; Schaerer D.; Capak P.; Yan L.; Vallini L.; Toft S.; Loiacono F.; Zamorani G.; Talia M.; Narayanan D.; Hathi N.P.; Lemaux B.C.; Boquien M.; Amorin R.; Ibar E.; Koekemoer A.M.; Mendez-Hernandez H.; Bardelli S.; Vergani D.; Zucca E.; Romano M.; Cimatti A.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/806102
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