Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published September 1, 2014 | Published + Submitted
Journal Article Open

The FMOS-Cosmos Survey of Star-Forming Galaxies at z ~ 1.6 II. The Mass-Metallicity Relation and the Dependence on Star Formation Rate and Dust Extinction


We investigate the relationships between stellar mass, gas-phase oxygen abundance (metallicity), star formation rate (SFR), and dust content of star-forming galaxies at z ~ 1.6 using Subaru/FMOS spectroscopy in the COSMOS field. The mass-metallicity (MZ) relation at z ~ 1.6 is steeper than the relation observed in the local universe. The steeper MZ relation at z ~ 1.6 is mainly due to evolution in the stellar mass where the MZ relation begins to turnover and flatten. This turnover mass is 1.2 dex larger at z ~ 1.6. The most massive galaxies at z ~ 1.6 (~10^(11) M_☉) are enriched to the level observed in massive galaxies in the local universe. The MZ relation we measure at z ~ 1.6 supports the suggestion of an empirical upper metallicity limit that does not significantly evolve with redshift. We find an anti-correlation between metallicity and SFR for galaxies at a fixed stellar mass at z ~ 1.6, which is similar to trends observed in the local universe. We do not find a relation between stellar mass, metallicity, and SFR that is independent of redshift; rather, our data suggest that there is redshift evolution in this relation. We examine the relation between stellar mass, metallicity, and dust extinction, and find that at a fixed stellar mass, dustier galaxies tend to be more metal rich. From examination of the stellar masses, metallicities, SFRs, and dust extinctions, we conclude that stellar mass is most closely related to dust extinction.

Additional Information

© 2014 American Astronomical Society. Received 2013 October 18; accepted 2014 July 8; published 2014 August 18. We thank the anonymous referee for a careful reading and for many useful suggestions that greatly improved this paper. This work is possible through the important contribution of Kentaro Aoki and the Subaru Telescope staff who assisted in acquiring much of the data presented in this work. This work was supported by World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan. This work has been partially supported by the Grant-in-Aid for the Scientific Research Fund under grant Nos. 22340056: N.S., 23224005: N.A., 25707010 and Program for Leading Graduate Schools PhD Professional: Gateway to Success in Frontier Asia commissioned by the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan. We are also grateful to INAF for regular support through grant "PRIN-2010." We acknowledge the importance of Mauna Kea within the indigenous Hawaiian community and with all respect say mahalo for the use of this sacred site.

Attached Files

Published - 0004-637X_792_1_75.pdf

Submitted - 1310.4950v3.pdf


Files (1.6 MB)
Name Size Download all
582.9 kB Preview Download
973.6 kB Preview Download

Additional details

August 22, 2023
October 17, 2023