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Title: COLD-MODE ACCRETION: DRIVING THE FUNDAMENTAL MASS–METALLICITY RELATION AT z ∼ 2

Abstract

We investigate the star formation rate (SFR) dependence on the stellar mass and gas-phase metallicity relation at z = 2 with MOSFIRE/Keck as part of the ZFIRE survey. We have identified 117 galaxies (1.98 ≤ z ≤ 2.56), with 8.9 ≤ log( M / M {sub ⊙}) ≤ 11.0, for which we can measure gas-phase metallicities. For the first time, we show a discernible difference between the mass–metallicity relation, using individual galaxies, when dividing the sample by low (<10 M {sub ⊙} yr{sup −1}) and high (>10 M {sub ⊙} yr{sup −1}) SFRs. At fixed mass, low star-forming galaxies tend to have higher metallicity than high star-forming galaxies. Using a few basic assumptions, we further show that the gas masses and metallicities required to produce the fundamental mass–metallicity relation and its intrinsic scatter are consistent with cold-mode accretion predictions obtained from the OWLS hydrodynamical simulations. Our results from both simulations and observations are suggestive that cold-mode accretion is responsible for the fundamental mass–metallicity relation at z = 2 and it demonstrates the direct relationship between cosmological accretion and the fundamental properties of galaxies.

Authors:
; ; ;  [1];  [2]; ;  [3];  [4]; ;  [5]; ;  [6];  [7]
  1. Swinburne University of Technology, Victoria 3122 (Australia)
  2. Department of Astronomy and Theoretical Astrophysics Center, University of California, Berkeley, CA 94720-3411 (United States)
  3. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States)
  4. Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia)
  5. Australian Astronomical Observatories, P.O. Box 915 North Ryde NSW 1670 (Australia)
  6. Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands)
  7. Department of Physics, University of California Davis, One Shields Avenue, Davis, CA 95616 (United States)
Publication Date:
OSTI Identifier:
22654270
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 826; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGY; EVOLUTION; FORECASTING; GALAXIES; MASS; METALLICITY; RED SHIFT; SIMULATION; STARS

Citation Formats

Kacprzak, Glenn G., Glazebrook, Karl, Nanayakkara, Themiya, Allen, Rebecca J., Van de Voort, Freeke, Tran, Kim-Vy H., Alcorn, Leo, Yuan, Tiantian, Cowley, Michael, Spitler, Lee, Labbé, Ivo, Straatman, Caroline, and Tomczak, Adam, E-mail: gkacprzak@astro.swin.edu.au. COLD-MODE ACCRETION: DRIVING THE FUNDAMENTAL MASS–METALLICITY RELATION AT z ∼ 2. United States: N. p., 2016. Web. doi:10.3847/2041-8205/826/1/L11.
Kacprzak, Glenn G., Glazebrook, Karl, Nanayakkara, Themiya, Allen, Rebecca J., Van de Voort, Freeke, Tran, Kim-Vy H., Alcorn, Leo, Yuan, Tiantian, Cowley, Michael, Spitler, Lee, Labbé, Ivo, Straatman, Caroline, & Tomczak, Adam, E-mail: gkacprzak@astro.swin.edu.au. COLD-MODE ACCRETION: DRIVING THE FUNDAMENTAL MASS–METALLICITY RELATION AT z ∼ 2. United States. doi:10.3847/2041-8205/826/1/L11.
Kacprzak, Glenn G., Glazebrook, Karl, Nanayakkara, Themiya, Allen, Rebecca J., Van de Voort, Freeke, Tran, Kim-Vy H., Alcorn, Leo, Yuan, Tiantian, Cowley, Michael, Spitler, Lee, Labbé, Ivo, Straatman, Caroline, and Tomczak, Adam, E-mail: gkacprzak@astro.swin.edu.au. 2016. "COLD-MODE ACCRETION: DRIVING THE FUNDAMENTAL MASS–METALLICITY RELATION AT z ∼ 2". United States. doi:10.3847/2041-8205/826/1/L11.
@article{osti_22654270,
title = {COLD-MODE ACCRETION: DRIVING THE FUNDAMENTAL MASS–METALLICITY RELATION AT z ∼ 2},
author = {Kacprzak, Glenn G. and Glazebrook, Karl and Nanayakkara, Themiya and Allen, Rebecca J. and Van de Voort, Freeke and Tran, Kim-Vy H. and Alcorn, Leo and Yuan, Tiantian and Cowley, Michael and Spitler, Lee and Labbé, Ivo and Straatman, Caroline and Tomczak, Adam, E-mail: gkacprzak@astro.swin.edu.au},
abstractNote = {We investigate the star formation rate (SFR) dependence on the stellar mass and gas-phase metallicity relation at z = 2 with MOSFIRE/Keck as part of the ZFIRE survey. We have identified 117 galaxies (1.98 ≤ z ≤ 2.56), with 8.9 ≤ log( M / M {sub ⊙}) ≤ 11.0, for which we can measure gas-phase metallicities. For the first time, we show a discernible difference between the mass–metallicity relation, using individual galaxies, when dividing the sample by low (<10 M {sub ⊙} yr{sup −1}) and high (>10 M {sub ⊙} yr{sup −1}) SFRs. At fixed mass, low star-forming galaxies tend to have higher metallicity than high star-forming galaxies. Using a few basic assumptions, we further show that the gas masses and metallicities required to produce the fundamental mass–metallicity relation and its intrinsic scatter are consistent with cold-mode accretion predictions obtained from the OWLS hydrodynamical simulations. Our results from both simulations and observations are suggestive that cold-mode accretion is responsible for the fundamental mass–metallicity relation at z = 2 and it demonstrates the direct relationship between cosmological accretion and the fundamental properties of galaxies.},
doi = {10.3847/2041-8205/826/1/L11},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 826,
place = {United States},
year = 2016,
month = 7
}
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