STELLAR MASS–GAS-PHASE METALLICITY RELATION AT 0.5 ≤ z ≤ 0.7: A POWER LAW WITH INCREASING SCATTER TOWARD THE LOW-MASS REGIME
Author
Guo, YichengKoo, David C.
Lu, Yu
Forbes, John C.
Rafelski, Marc
Trump, Jonathan R.
Amorín, Ricardo
Barro, Guillermo
Davé, Romeel
Faber, S. M.
Hathi, Nimish
Yesuf, Hassen
Cooper, Michael
Dekel, Avishai
Guhathakurta, Puragra
Kirby, Evan N.
Koekemoer, Anton M.
Pérez-González, Pablo G.
Lin, Lihwai
Newman, Jeffery A.
Primack, Joel R.
Rosario, David J.
Willmer, Christopher N. A.
Yan, Renbin
Affiliation
Univ Arizona, Steward ObservIssue Date
2016-05-11Keywords
galaxies: abundancesgalaxies: dwarf
galaxies: evolution
galaxies: formation
galaxies: fundamental parameters
galaxies: ISM
Metadata
Show full item recordPublisher
IOP PUBLISHING LTDCitation
STELLAR MASS–GAS-PHASE METALLICITY RELATION AT 0.5 ≤ z ≤ 0.7: A POWER LAW WITH INCREASING SCATTER TOWARD THE LOW-MASS REGIME 2016, 822 (2):103 The Astrophysical JournalJournal
The Astrophysical JournalRights
© 2016. The American Astronomical Society. All rights reserved.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
We present the stellar mass (M-*)-gas-phase metallicity relation (MZR) and its scatter at intermediate redshifts (0.5 <= z <= 0.7) for 1381 field galaxies collected from deep spectroscopic surveys. The star formation rate (SFR) and color at a given M-* of this magnitude-limited (R less than or similar to 24 AB) sample are representative of normal star-forming galaxies. For masses below 10(9) M-circle dot, our sample of 237 galaxies is similar to 10 times larger than those in previous studies beyond the local universe. This huge gain in sample size enables superior constraints on the MZR and its scatter in the low-mass regime. We find a power-law MZR at 10(8) M-circle dot < M-* < 10(11) M-circle dot: 12 + log (O/H) = (5.83 +/- 0.19)+(0.30 +/- 0.02) log (M-*/M-circle dot). At 10(9) M-circle dot < M-* < 10(10.5) M-circle dot, our MZR shows agreement with others measured at similar redshifts in the literature. Our power-law slope is, however, shallower than the extrapolation of the MZRs of others to masses below 10(9) M-circle dot. The SFR dependence of the MZR in our sample is weaker than that found for local galaxies (known as the fundamental metallicity relation). Compared to a variety of theoretical models, the slope of our MZR for low-mass galaxies agrees well with predictions incorporating supernova energy-driven winds. Being robust against currently uncertain metallicity calibrations, the scatter of the MZR serves as a powerful diagnostic of the stochastic history of gas accretion, gas recycling, and star formation of low-mass galaxies. Our major result is that the scatter of our MZR increases as M-* decreases. Our result implies that either the scatter of the baryonic accretion rate (sigma((M) over dot)) or the scatter of the M-*-M-halo relation (sigma(SHMR)) increases as M-* decreases. Moreover, our measure of scatter at z = 0.7 appears consistent with that found for local galaxies. This lack of redshift evolution constrains models of galaxy evolution to have both sigma((M) over dot) and sigma(SHMR) remain unchanged from z = 0.7 to z = 0.ISSN
1538-4357Version
Final published versionSponsors
NSF [AST-0808133, AST-1405962]; NASA through a grant from the Space Telescope Science Institute [HST-GO-12060, HST-AR-13891]; NASA [NAS 5-26555]; NASA through Hubble Fellowship - Space Telescope Science Institute [51330]; ISF [24/12]; I-CORE Program of the PBC ISF grant [1829/12]; Spanish MINECO [AYA2012-31277]; [HST-AR-13909]Additional Links
http://stacks.iop.org/0004-637X/822/i=2/a=103?key=crossref.cb5a8f7fd58e1cbf9ac37932d58d5913ae974a485f413a2113503eed53cd6c53
10.3847/0004-637X/822/2/103