TY - JOUR
T1 - MOSEL
T2 - Strong [OIII] 5007 Å emitting galaxies at (3 < z < 4) from the ZFOURGE survey
AU - Tran, Kim-Vy H.
AU - Forrest, Ben
AU - Alcorn, Leo Y.
AU - Yuan, Tiantian
AU - Nanayakkara, Themiya
AU - Cohn, Jonathan
AU - Cowley, Michael
AU - Glazebrook, Karl
AU - Gupta, Anshu
AU - Kacprzak, Glenn G.
AU - Kewley, Lisa
AU - Labbé, Ivo
AU - Papovich, Casey
AU - Spitler, Lee
AU - Straatman, Caroline M. S.
AU - Tomczak, Adam
N1 - Copyright 2020 The American Astronomical Society. First published in the Astrophysical Journal, 898(1), 45, 2020, published by IOP Publishing. The original publication is available at https://doi.org/10.3847/1538-4357/ab8cba. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2020/7/21
Y1 - 2020/7/21
N2 - To understand how strong emission-line galaxies (SELGs) contribute to the overall growth of galaxies and star formation history of the universe, we target SELGs from the ZFOURGE imaging survey that have blended Hβ+[O III] rest-frame equivalent widths of >230 Å and 2.5 < zphot < 4.0. Using Keck/MOSFIRE, we measure 49 redshifts for galaxies brighter than Ks = 25 mag as part of our Multi-Object Spectroscopic Emission Line (MOSEL) survey. Our spectroscopic success rate is ∼53% and z uncertainty is σz = [Δz/(1+z)] = 0.0135. We confirm 31 ELGs at 3< zspec < 3.8, and show that SELGs have spectroscopic rest-frame [O III]5007 Å equivalent widths of 100-500 Å and tend to be lower-mass systems [log(M*/M⊙ ) ∼ 8.2-9.6] compared with more typical star-forming galaxies. The SELGs lie ∼0.9 dex above the star-forming main sequence at z ∼ 3.5 and have high inferred gas fractions of fgas ⪆ 60%, i.e., the inferred gas masses can easily fuel a starburst to double stellar masses within ∼10-100 Myr. Combined with recent results using ZFOURGE, our analysis indicates that (1) strong [O III]5007 Å emission signals an early episode of intense stellar growth in low-mass [M*< 0.1,M*] galaxies and (2) many, if not most, galaxies at z > 3 go through this starburst phase. If true, low-mass galaxies with strong [O III]5007 Å emission (EWrest > 200 Å) may be an increasingly important source of ionizing UV radiation at z > 3.
AB - To understand how strong emission-line galaxies (SELGs) contribute to the overall growth of galaxies and star formation history of the universe, we target SELGs from the ZFOURGE imaging survey that have blended Hβ+[O III] rest-frame equivalent widths of >230 Å and 2.5 < zphot < 4.0. Using Keck/MOSFIRE, we measure 49 redshifts for galaxies brighter than Ks = 25 mag as part of our Multi-Object Spectroscopic Emission Line (MOSEL) survey. Our spectroscopic success rate is ∼53% and z uncertainty is σz = [Δz/(1+z)] = 0.0135. We confirm 31 ELGs at 3< zspec < 3.8, and show that SELGs have spectroscopic rest-frame [O III]5007 Å equivalent widths of 100-500 Å and tend to be lower-mass systems [log(M*/M⊙ ) ∼ 8.2-9.6] compared with more typical star-forming galaxies. The SELGs lie ∼0.9 dex above the star-forming main sequence at z ∼ 3.5 and have high inferred gas fractions of fgas ⪆ 60%, i.e., the inferred gas masses can easily fuel a starburst to double stellar masses within ∼10-100 Myr. Combined with recent results using ZFOURGE, our analysis indicates that (1) strong [O III]5007 Å emission signals an early episode of intense stellar growth in low-mass [M*< 0.1,M*] galaxies and (2) many, if not most, galaxies at z > 3 go through this starburst phase. If true, low-mass galaxies with strong [O III]5007 Å emission (EWrest > 200 Å) may be an increasingly important source of ionizing UV radiation at z > 3.
UR - http://www.scopus.com/inward/record.url?scp=85088941230&partnerID=8YFLogxK
U2 - 10.3847/1538-4357/ab8cba
DO - 10.3847/1538-4357/ab8cba
M3 - Article
AN - SCOPUS:85088941230
SN - 0004-637X
VL - 898
SP - 1
EP - 13
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 45
ER -