TY - JOUR

T1 - Low Star Formation Activity and Low Gas Content of Quiescent Galaxies at z=3.5-4.0 Constrained with ALMA

AU - Suzuki, Tomoko L.

AU - Glazebrook, Karl

AU - Schreiber, Corentin

AU - Kodama, Tadayuki

AU - Kacprzak, Glenn G.

AU - Leiton, Roger

AU - Nanayakkara, Themiya

AU - Oesch, Pascal A.

AU - Papovich, Casey

AU - Spitler, Lee

AU - Straatman, Caroline M. S.

AU - Kim-Vy Tran, null

AU - Wang, Tao

PY - 2022/8/31

Y1 - 2022/8/31

N2 - The discovery in deep near-infrared surveys of a population of massive quiescent galaxies at z > 3 has given rise to the question of how they came to be quenched so early in the history of the universe. Measuring their molecular gas properties can distinguish between physical processes where they stop forming stars due to a lack of fuel versus those where the star formation efficiency is reduced and the gas is retained. We conducted Atacama Large Millimeter/submillimeter Array observations of four quiescent galaxies at z = 3.5-4.0 found by the Fourstar Galaxy Evolution Survey and a serendipitous optically dark galaxy at z = 3.71. We aim to investigate the presence of dust-obscured star formation and their gas content by observing the dust continuum emission at Band 7 and the atomic carbon [C i]((3) P (1)-(3) P (0)) line at 492.16 GHz. Among the four quiescent galaxies, only one source is detected in the dust continuum at lambda (obs) = 870 mu m. The submillimeter observations confirm their passive nature, and all of them are located more than four times below the main sequence of star-forming galaxies at z = 3.7. None of the targets are detected in [C i], constraining their gas-mass fractions to be z = 3.7. These results support scenarios where massive galaxies at z = 3.5-4.0 quench by consuming/expelling all the gas rather than by reducing the efficiency of the conversion of their gas into stars.

AB - The discovery in deep near-infrared surveys of a population of massive quiescent galaxies at z > 3 has given rise to the question of how they came to be quenched so early in the history of the universe. Measuring their molecular gas properties can distinguish between physical processes where they stop forming stars due to a lack of fuel versus those where the star formation efficiency is reduced and the gas is retained. We conducted Atacama Large Millimeter/submillimeter Array observations of four quiescent galaxies at z = 3.5-4.0 found by the Fourstar Galaxy Evolution Survey and a serendipitous optically dark galaxy at z = 3.71. We aim to investigate the presence of dust-obscured star formation and their gas content by observing the dust continuum emission at Band 7 and the atomic carbon [C i]((3) P (1)-(3) P (0)) line at 492.16 GHz. Among the four quiescent galaxies, only one source is detected in the dust continuum at lambda (obs) = 870 mu m. The submillimeter observations confirm their passive nature, and all of them are located more than four times below the main sequence of star-forming galaxies at z = 3.7. None of the targets are detected in [C i], constraining their gas-mass fractions to be z = 3.7. These results support scenarios where massive galaxies at z = 3.5-4.0 quench by consuming/expelling all the gas rather than by reducing the efficiency of the conversion of their gas into stars.

KW - WIDE-FIELD SURVEY

KW - MOLECULAR GAS

KW - COSMOS FIELD

KW - SCALING RELATIONS

KW - PASSIVE GALAXIES

KW - MASSIVE GALAXIES

KW - FORMING GALAXIES

KW - STELLAR

KW - DUST

KW - EVOLUTION

U2 - 10.3847/1538-4357/ac7ce3

DO - 10.3847/1538-4357/ac7ce3

M3 - Journal article

VL - 936

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 61

ER -