A solar metallicity galaxy at z > 7? Possible detection of the [N II] 122 mu m and [O III] 52 mu m lines
Artikel i vetenskaplig tidskrift, 2023
We present the first detection of the [NII] 122 mu m and [O III ] 52 mu m lines for a reionization-epoch galaxy. Based on these lines and previous [C II ] 158 mu m and [O III ] 88 mu m measurements, using two different radiati ve transfer models of the interstellar medium, we estimate an upper limit on electron density of < 500 cm(-3) and an approximate gas-phase metallicity of Z/Z(circle dot) similar to 1.1 +/- 0.2 for A1689-zD1, a gravitationally lensed dusty galaxy at z = 7.133. Other measurements or indicators of metallicity so far in galaxy interstellar media at z greater than or similar to 6 are typically an order of magnitude lower than this. The unusually high metallicity makes A1689-zD1 inconsistent with the fundamental metallicity relation, although there is likely significant dust obscuration of the stellar mass, which may partly resolve the inconsistency. Given a solar metallicity, the dust-to-metals ratio is a factor of several lower than expected, hinting that galaxies be yond z similar to 7 may hav e lower dust formation efficiency . Finally , the inferred nitrogen enrichment compared to oxygen, on which the metallicity measurement depends, indicates that star formation in the system is older than about 250 Myr, pushing the beginnings of this galaxy to z > 10.
galaxies:ISM
galaxies:high-redshift
submillimetre:galaxies
ISM:abundances
galaxies:individual:(A1689-zD1)
Författare
Meghana Killi
Köpenhamns universitet
Darach Watson
Köpenhamns universitet
Seiji Fujimoto
Köpenhamns universitet
Hollis Akins
The University of Texas at Austin
Kirsten Knudsen
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
Johan Richard
Université de Lyon
Yuichi Harikane
University College London (UCL)
University of Tokyo
Dimitra Rigopoulou
University of Oxford
European University Cyprus
Francesca Rizzo
Köpenhamns universitet
Michele Ginolfi
Universita degli Studi di Firenze
Gergo Popping
European Southern Observatory Santiago
Vasily Kokorev
Köpenhamns universitet
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 521 2 2526-2534Ämneskategorier
Astronomi, astrofysik och kosmologi
Sannolikhetsteori och statistik
Fusion, plasma och rymdfysik
DOI
10.1093/mnras/stad687