TY - JOUR
T1 - Evident black hole-bulge coevolution in the distant universe
AU - Yang, G.
AU - Brandt, W. N.
AU - Alexander, D. M.
AU - Chen, C. T.J.
AU - Ni, Q.
AU - Vito, F.
AU - Zhu, F. F.
N1 - Funding Information:
We thank the referee for helpful feedback that improved this work. We thank Robin Ciardullo, Mara Salvato, Ian Smail, Yongquan Xue, and Wenfei Yu for helpful discussions. GY, WNB, and QN acknowledge support from Chandra X-ray Center grant AR8-19016X, NASA grant NNX17AF07G, NASA ADP grant 80NSSC18K0878, and the V.M. Willaman Endowment. DMA acknowledges the Science and Technology Facilities Council through grant ST/L00075X/1. FV acknowledges financial support from CONICYT and CASSACA through the Fourth call for tenders of the CAS-CONICYT Fund. The Chandra Guaranteed Time Observations (GTO) for the GOODS-N were selected by the ACIS Instrument Principal Investigator, Gordon P. Garmire, currently of the Huntingdon Institute for X-ray Astronomy, LLC, which is under contract to the Smithsonian Astrophysical Observatory via Contract SV2-82024. This project uses ASTROPY (a PYTHON package; see Astropy Collaboration 2018).
Publisher Copyright:
© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2019/2/28
Y1 - 2019/2/28
N2 - Observations in the local universe show a tight correlation between the masses of supermassive black holes (SMBHs; MBH) and host-galaxy bulges (Mbulge), suggesting a strong connection between SMBH and bulge growth.However, direct evidence for such a connection in the distant universe remains elusive. We have studied sample-averaged SMBH accretion rate (BHAR) for bulge-dominated galaxies at z = 0.5–3. While previous observations found BHAR is strongly related to host-galaxy stellar mass (M*) for the overall galaxy population, our analyses show that, for the bulge-dominated population, BHAR is mainly related to SFR rather than M*. This BHAR–SFR relation is highly significant, e.g. 9.0σ (Pearson statistic) at z = 0.5–1.5. Such a BHAR–SFR connection does not exist among our comparison sample of galaxies that are not bulge dominated, for which M* appears to be the main determinant of SMBH accretion. This difference between the bulge-dominated and comparison samples indicates that SMBHs only coevolve with bulges rather than the entire galaxies, explaining the tightness of the local MBH−Mbulge correlation. Our best-fitting BHAR–SFR relation for the bulge-dominated sample is log BHAR = log SFR − (2.48 ± 0.05) (solar units). The best-fitting BHAR/SFR ratio (10−2.48) for bulge-dominated galaxies is similar to the observed MBH/Mbulge values in the local universe. Our results reveal that SMBH and bulge growth are in lockstep, and thus non-causal scenarios of merger averaging are unlikely the origin of the MBH−Mbulge correlation. This lockstep growth also predicts that the MBH−Mbulge relation should not have strong redshift dependence.
AB - Observations in the local universe show a tight correlation between the masses of supermassive black holes (SMBHs; MBH) and host-galaxy bulges (Mbulge), suggesting a strong connection between SMBH and bulge growth.However, direct evidence for such a connection in the distant universe remains elusive. We have studied sample-averaged SMBH accretion rate (BHAR) for bulge-dominated galaxies at z = 0.5–3. While previous observations found BHAR is strongly related to host-galaxy stellar mass (M*) for the overall galaxy population, our analyses show that, for the bulge-dominated population, BHAR is mainly related to SFR rather than M*. This BHAR–SFR relation is highly significant, e.g. 9.0σ (Pearson statistic) at z = 0.5–1.5. Such a BHAR–SFR connection does not exist among our comparison sample of galaxies that are not bulge dominated, for which M* appears to be the main determinant of SMBH accretion. This difference between the bulge-dominated and comparison samples indicates that SMBHs only coevolve with bulges rather than the entire galaxies, explaining the tightness of the local MBH−Mbulge correlation. Our best-fitting BHAR–SFR relation for the bulge-dominated sample is log BHAR = log SFR − (2.48 ± 0.05) (solar units). The best-fitting BHAR/SFR ratio (10−2.48) for bulge-dominated galaxies is similar to the observed MBH/Mbulge values in the local universe. Our results reveal that SMBH and bulge growth are in lockstep, and thus non-causal scenarios of merger averaging are unlikely the origin of the MBH−Mbulge correlation. This lockstep growth also predicts that the MBH−Mbulge relation should not have strong redshift dependence.
UR - http://www.scopus.com/inward/record.url?scp=85067174431&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85067174431&partnerID=8YFLogxK
U2 - 10.1093/mnras/stz611
DO - 10.1093/mnras/stz611
M3 - Article
AN - SCOPUS:85067174431
SN - 0035-8711
VL - 485
SP - 3721
EP - 3737
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -