Detection of the [O i] 63 μm emission line from the z = 6.04 quasar J2054-0005
Nozomi Ishii (University of Tsukuba, Systems Engineering Consultants Co., Ltd.)
Takuya Hashimoto (University of Tsukuba)
Carl Ferkinhoff (Winona State University)
Matus Rybak (Universiteit Leiden, TU Delft - Tera-Hertz Sensing, SRON–Netherlands Institute for Space Research)
Akio K. Inoue (Waseda University)
Tomonari Michiyama (Shunan University)
Darko Donevski (National Center for Nuclear Research, SISSA)
Seiji Fujimoto (The University of Texas at Austin)
undefined More Authors (External organisation)
Dragan Salak (Hokkaido University)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
We report the highest-redshift detection of [O i] 63 m from a luminous quasar, J20540005, at based on the Atacama Large Millimeter/sub-millimeter Array (ALMA) Band 9 observations. The [O i] 63 m line luminosity is, corresponding to the [O i] 63 m-to-far-infrared luminosity ratio of 6.7, which is consistent with the value obtained in the local Universe. Remarkably, [O i] 63 m is as bright as [C ii] 158 m, resulting in the [O i]-to-[C ii] line luminosity ratio of. Based on a careful comparison of the luminosity ratios of [O i] 63 m, [C ii] 158 m, and dust continuum emission to models of photodissociation regions, we find that J20540005 has a gas density and an incident far-ultraviolet radiation field of, showing that [O i] 63 m serves as an important coolant of the dense and warm gas in J20540005. A close examination of the [O i] and [C ii] line profiles suggests that the [O i] line may be partially self-absorbed; however, deeper observations are needed to verify this conclusion. Regardless, the gas density and incident radiation field are in broad agreement with the values obtained in nearby star-forming galaxies and objects with [O i] 63 m observations at -3 with the Herschel Space Observatory. These results demonstrate the power of ALMA high-frequency observations targeting [O i] 63 m to examine the properties of photodissociation regions in high-redshift galaxies.