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arXiv · 1703.07797

[CII] 158 micron Emission from the Host Galaxies of Damped Lyman Alpha Systems

Marcel Neeleman·Nissim Kanekar·J. Xavier Prochaska·Marc Rafelski·Chris L. Carilli·Arthur M. Wolfe
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Abstract

Gas surrounding high redshift galaxies has been studied through observations of absorption line systems toward background quasars for decades. However, it has proven difficult to identify and characterize the galaxies associated with these absorbers due to the intrinsic faintness of the galaxies compared to the quasars at optical wavelengths. Utilizing the Atacama Large Millimeter/Submillimeter Array, we report on detections of [CII] 158 micron line and dust continuum emission from two galaxies associated with two such absorbers at a redshift of z~4. Our results indicate that the hosts of these high-metallicity absorbers have physical properties similar to massive star-forming galaxies and are embedded in enriched neutral hydrogen gas reservoirs that extend well beyond the star-forming interstellar medium of these galaxies.

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Marcel Neeleman, Nissim Kanekar, J. Xavier Prochaska, Marc Rafelski, Chris L. Carilli, Arthur M. Wolfe. 2017-03-22. [CII] 158 micron Emission from the Host Galaxies of Damped Lyman Alpha Systems. https://doi.org/10.1126/science.aal1737

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