7th of August 2017 |
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A Massive Dusty Star-forming Galaxy at z = 6.9 |
by Strandet et al. |
Strandet et al. report the discovery and constrain the physical conditions of the
interstellar medium of the highest-redshift millimeter-selected dusty
star-forming galaxy to date, SPT0311-58, at z=6.9 (corresponding
to an age of the Universe of only 780 million years). SPT0311-58 was discovered via its
1.4 mm thermal dust continuum emission in the South Pole Telescope
survey. The spectroscopic redshift was determined via
ALMA (Atacama Large Millimeter/submillimeter Array) 3mm band observations
and subsequently
confirmed by the detections of other spectral lines with the Australia Telescope
Compact Array and APEX. These observations
enable the
properties of the inter-stellar medium (ISM) to be constrained,
revealing that SPT0311-58 is extremely
massive. Such a large mass and intense star formation is very rare for a
source well into the epoch of reionization.
The image above shows several of the spectral line detections,
all different transitions of the carbon monoxide molecule, confirming
the high redshift for SPT0311-58, with the left-hand panel being the
ATCA 7mm band detection, and the other two being ALMA detections.
The results are described in the recent paper by Strandet et al.
Astrophysical Journal Letters, |