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arXiv · 1907.02721

A luminous molecular gas pair beyond redshift 7

Ekaterina Koptelova·Chorng-Yuan Hwang
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Abstract

We report the first detection of molecular gas beyond redshift 7. The molecular gas is associated with the host galaxy of the quasar candidate PSO J145.5964+19.3565 and its companion PSO J145.5964+19.3565N separated by 20.7 kpc. The molecular gas of both companions is detected in two rotational transition lines of carbon monoxide, CO(6-5) and CO(7-6). We also detected the Lyman-alpha line of PSO J145.5964+19.3565 at z=7.08. The Lyman-alpha line emission is extended and might represent the blended emission of two different sources at a separation of <5 kpc. The detected CO and Lyman-alpha emission likely originate from a system of interacting star-forming galaxies that might host a quasar(s). We also report the detection of a new emission line from the system which is a possible 793.62-GHz water maser line.

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Ekaterina Koptelova, Chorng-Yuan Hwang. 2019-07-05. A luminous molecular gas pair beyond redshift 7. https://doi.org/10.3847/2041-8213%2Fab2ed9

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