Planck's Dusty GEMS. II. Extended [CII] emission and absorption in the Garnet at z=3.4 seen with ALMA
Journal article, 2016

We present spatially resolved ALMA [CII] observations of the bright (flux density S350 = 400 mJy at 350 μm), gravitationally lensed, starburst galaxy PLCK G045.1+61.1 at z = 3.427, the "Garnet". This source is part of our set of "Planck's Dusty GEMS", discovered with the Planck's all-sky survey. Two emission-line clouds with a relative velocity offset of ~600 km s-1 extend towards north-east and south-west, respectively, of a small, intensely star-forming clump with a star-formation intensity of 220 M⊙ yr-1 kpc-2, akin to maximal starbursts. [CII] is also seen in absorption, with a redshift of +350 km s-1 relative to the brightest CO component. [CII] absorption has previously only been found in the Milky Way along sightlines toward bright high-mass star-forming regions, and this is the first detection in another galaxy. Similar to Galactic environments, the [CII] absorption feature is associated with [CI] emission, implying that this is diffuse gas shielded from the UV radiation of the clump, and likely at large distances from the clump. Since absorption can only be seen in front of a continuum source, the gas in this structure can definitely be attributed to gas flowing towards the clump. The absorber could be part of a cosmic filament or merger debris being accreted onto the galaxy. We discuss our results also in light of the on-going debate of the origin of the [CII] deficit in dusty star-forming galaxies.

galaxies: high-redshift

galaxies: kinematics and dynamics

galaxies: starburst

infrared: galaxies

galaxies: ISM

Galaxy: formation


N. Nesvadba

University of Paris-Sud

Institut d'Astrophysique Spatiale

University Paris-Saclay

Centre national de la recherche scientifique (CNRS)

R. Kneissl

European Southern Observatory Santiago

Atacama Large Millimeter-submillimeter Array (ALMA)

R. Canameras

Institut d'Astrophysique Spatiale

University of Paris-Sud

University Paris-Saclay

Centre national de la recherche scientifique (CNRS)

F. Boone

University of Toulouse

E. Falgarone

LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres

B. Frye

University of Arizona

M. Gerin

LERMA - Laboratoire d'Etudes du Rayonnement et de la Matiere en Astrophysique et Atmospheres

Sabine König

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

Guilaine Lagache

Laboratoire d'Astrophysique de Marseille

E. Le Floc'H

The French Alternative Energies and Atomic Energy Commission (CEA)

Sangeeta Malhotra

Arizona State University

D. Scott

University of British Columbia (UBC)

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 593 L2- L2

Subject Categories

Astronomy, Astrophysics and Cosmology


Basic sciences



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