@article{dd9694a70d7543cd857d38e44281b9da,
title = "Does the Lockstep Growth between Black Holes and Bulges Create Their Mass Relation?",
abstract = "Recent studies have revealed a strong relation between the sample-averaged black hole (BH) accretion rate (BHAR) and star formation rate (SFR) among bulge-dominated galaxies—i.e., “lockstep” BH-bulge growth—in the distant universe. This relation might be closely connected to the BH-bulge mass correlation observed in the local universe. To further understand BH-bulge coevolution, we present Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1) or CO(3-2) observations of seven star-forming bulge-dominated galaxies at z = 0.5-2.5. Using the ALMA data, we detect significant (>3σ) CO emission from four objects. For our sample of seven galaxies, we measure (or constrain with upper limits) their CO line fluxes and estimate their molecular gas masses (M gas). We also estimate their stellar masses (M star) and SFRs, by modeling their spectral energy distributions. Using these physical properties, we derive the gas depletion timescales (τ dep ≡ M gas/SFR) and compare them with the bulge/BH growth timescales (τ grow ≡ M star/SFR ∼ M BH/BHAR). Our sample generally has τ dep shorter than τ grow by a median factor of ≳4, indicating that the cold gas will be depleted before significant bulge/BH growth takes place. This result suggests that BH-bulge lockstep growth is mainly responsible for maintaining the mass relation, not creating it. We note that our sample is small and limited to z < 2.5; JWST and ALMA will be able to probe to higher redshifts in the near future.",
author = "Guang Yang and Brandt, {W. N.} and Alexander, {David M.} and M{\'e}d{\'e}ric Boquien and Qingling Ni and Casey Papovich and Spilker, {Justin S.} and Fabio Vito and Walsh, {Jonelle L.} and Chengpeng Zhang",
note = "Funding Information: We thank the referee for helpful feedback that improved this work. We thank Guillermo Barro and Ian Smail for helpful discussions. G.Y., C.P., J.S.S., J.L.W., and C.P.Z. acknowledge support from the George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University. W.N.B. acknowledges support from Chandra X-ray Center grant GO9-20099X and the V.M. Willaman Endowment. D.M.A. thanks the Science and Technology Facilities Council for support through grant code ST/T000244/1. M.B. gratefully acknowledges support from the ANID BASAL project FB210003 and from the FONDECYT regular grant 1211000. The authors acknowledge the Texas A&M University Brazos HPC cluster and Texas A&M High Performance Research Computing Resources (HPRC; http://hprc.tamu.edu ), which contributed to the research reported here. We thank the ALMA helpdesk for their help with ALMA data retrieval and reduction. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.1.00678.S. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. This work has made use of the Rainbow Cosmological Surveys Database, which is operated by the Centro de Astrobiolog{\'i}a (CAB/INTA), partnered with the University of California Observatories at Santa Cruz (UCO/Lick, UCSC). Funding Information: We thank the referee for helpful feedback that improved this work. We thank Guillermo Barro and Ian Smail for helpful discussions. G.Y., C.P., J.S.S., J.L.W., and C.P.Z. acknowledge support from the George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University. W.N.B. acknowledges support from Chandra X-ray Center grant GO9-20099X and the V.M. Willaman Endowment. D.M.A. thanks the Science and Technology Facilities Council for support through grant code ST/T000244/1. M.B. gratefully acknowledges support from the ANID BASAL project FB210003 and from the FONDECYT regular grant 1211000. The authors acknowledge the Texas A&M University Brazos HPC cluster and Texas A&M High Performance Research Computing Resources (HPRC; http://hprc.tamu.edu), which contributed to the research reported here. We thank the ALMA helpdesk for their help with ALMA data retrieval and reduction. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.1.00678.S. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. This work has made use of the Rainbow Cosmological Surveys Database, which is operated by the Centro de Astrobiolog{\'i}a (CAB/INTA), partnered with the University of California Observatories at Santa Cruz (UCO/Lick, UCSC). Publisher Copyright: {\textcopyright} 2022. The Author(s). Published by the American Astronomical Society.",
year = "2022",
month = dec,
day = "1",
doi = "10.3847/1538-4357/ac9c68",
language = "English (US)",
volume = "940",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",
}