ZFIRE: similar stellar growth in hα-emitting cluster and field galaxies at z ∼ 2

Journal Article · Tue Jan 10 04:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/834/2/101· OSTI ID:22869538

Tran, Kim-Vy H.; Alcorn, Leo Y.; Papovich, Casey; Quadri, Ryan ^[1]; Kacprzak, Glenn G.; Nanayakkara, Themiya; Glazebrook, Karl ^[2]; Straatman, Caroline; Labbé, Ivo ^[3]; Yuan, Tiantian; Kewley, Lisa J. ^[4]; Cowley, Michael; Spitler, Lee R. ^[5]; Davé, Romeel ^[6]; Martizzi, Davidé ^[7]; Tomczak, Adam ^[8]

---

1. George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States)
2. Swinburne University of Technology, Hawthorn, VIC 3122 (Australia)
3. Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands)
4. Research School of Astronomy and Astrophysics, The Australian National University, Cotter Road, Weston Creek, ACT 2611 (Australia)
5. Department of Physics and Astronomy, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109 (Australia)
6. University of the Western Cape, Bellville, Cape Town, 7535 (South Africa)
7. Department of Astronomy, University of California, Berkeley, CA 95720 (United States)
8. Department of Physics, University of California, Davis, CA 95616 (United States)

We compare galaxy scaling relations as a function of environment at z∼2 with our ZFIRE survey{sup 12} where we have measured Hα fluxes for 90 star-forming galaxies selected from a mass-limited (log(M{sub ⋆}/M{sub ⊙})>9) sample based on ZFOURGE.{sup 13} The cluster galaxies (37) are part of a confirmed system at z = 2.095 and the field galaxies (53) are at 1.9 2 × 10{sup 11} L{sub ⊙}). Because the luminous IR galaxies in our combined sample are ∼5 times more massive than the low-IR galaxies, their radii are ∼70% larger. To track stellar growth, we separate galaxies into those that lie above, on, or below the Hα star-forming main sequence (SFMS) using ΔSFR(M{sub ⋆}) = ±0.2 dex. Galaxies above the SFMS (starbursts) tend to have higher Hα SFR surface densities and younger light-weighted stellar ages than galaxies below the SFMS. Our results indicate that starbursts (+SFMS) in the cluster and field at z∼2 are growing their stellar cores. Lastly, we compare to the (SFR–M{sub ⋆}) relation from Rhapsody-G cluster simulations and find that the predicted slope is nominally consistent with the observations. However, the predicted cluster SFRs tend to be too low by a factor of ∼2, which seems to be a common problem for simulations across environment.

• OSTI ID: 22869538
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 834; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
APPROXIMATIONS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
DENSITY
DISTRIBUTION
FUNCTIONS
GALACTIC EVOLUTION
GALAXIES
GALAXY CLUSTERS
MASS
PARTICLE TRACKS
STAR EVOLUTION
STARS
SURFACES
UNIVERSE