TY - JOUR
T1 - The Megamaser Cosmology Project. X. High-resolution Maps and Mass Constraints for SMBHs
AU - Zhao, W.
AU - Braatz, J. A.
AU - Condon, J. J.
AU - Lo, K. Y.
AU - Reid, M. J.
AU - Henkel, C.
AU - Pesce, D. W.
AU - Greene, J. E.
AU - Gao, F.
AU - Kuo, C. Y.
AU - Impellizzeri, C. M.V.
N1 - Funding Information:
This research has made use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. We thank the referee for helpful comments, and we are grateful to the NRAO VLBA and GBT staff for their many contributions to the Megamaser Cosmology Project. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This work was partially carried out within the Collaborative Research Council 956, subproject A6, funded by the Deutsche Forschungsge-meinschaft (DFG). Facilities: Effelsberg, GBT, VLBA.
Publisher Copyright:
© 2018. The American Astronomical Society.
PY - 2018/2/20
Y1 - 2018/2/20
N2 - We present high-resolution (submas) Very Long Baseline Interferometry maps of nuclear H2O megamasers for seven galaxies. In UGC 6093, the well-aligned systemic masers and high-velocity masers originate in an edge-on, flat disk and we determine the mass of the central supermassive black holes (SMBH) to be M SMBH = 2.58 ×107 M o (±7%). For J1346+5228, the distribution of masers is consistent with a disk, but the faint high-velocity masers are only marginally detected, and we constrain the mass of the SMBH to be in the range (1.5-2.0) ×107 M o. The origin of the masers in Mrk 1210 is less clear, as the systemic and high-velocity masers are misaligned and show a disorganized velocity structure. We present one possible model in which the masers originate in a tilted, warped disk, but we do not rule out the possibility of other explanations including outflow masers. In NGC 6926, we detect a set of redshifted masers, clustered within a parsec of each other, and a single blueshifted maser about 4.4 pc away, an offset that would be unusually large for a maser disk system. Nevertheless, if it is a disk system, we estimate the enclosed mass to be M SMBH < 4.8 ×107 M o. For NGC 5793, we detect redshifted masers spaced about 1.4 pc from a clustered set of blueshifted features. The orientation of the structure supports a disk scenario as suggested by Hagiwara et al. We estimate the enclosed mass to be M SMBH < 1.3 ×107 M o. For NGC 2824 and J0350-0127, the masers may be associated with parsec- or subparsec-scale jets or outflows.
AB - We present high-resolution (submas) Very Long Baseline Interferometry maps of nuclear H2O megamasers for seven galaxies. In UGC 6093, the well-aligned systemic masers and high-velocity masers originate in an edge-on, flat disk and we determine the mass of the central supermassive black holes (SMBH) to be M SMBH = 2.58 ×107 M o (±7%). For J1346+5228, the distribution of masers is consistent with a disk, but the faint high-velocity masers are only marginally detected, and we constrain the mass of the SMBH to be in the range (1.5-2.0) ×107 M o. The origin of the masers in Mrk 1210 is less clear, as the systemic and high-velocity masers are misaligned and show a disorganized velocity structure. We present one possible model in which the masers originate in a tilted, warped disk, but we do not rule out the possibility of other explanations including outflow masers. In NGC 6926, we detect a set of redshifted masers, clustered within a parsec of each other, and a single blueshifted maser about 4.4 pc away, an offset that would be unusually large for a maser disk system. Nevertheless, if it is a disk system, we estimate the enclosed mass to be M SMBH < 4.8 ×107 M o. For NGC 5793, we detect redshifted masers spaced about 1.4 pc from a clustered set of blueshifted features. The orientation of the structure supports a disk scenario as suggested by Hagiwara et al. We estimate the enclosed mass to be M SMBH < 1.3 ×107 M o. For NGC 2824 and J0350-0127, the masers may be associated with parsec- or subparsec-scale jets or outflows.
KW - accretion, accretion disks
KW - galaxies: ISM
KW - galaxies: Seyfert
KW - galaxies: active
KW - galaxies: nuclei
UR - http://www.scopus.com/inward/record.url?scp=85042697163&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85042697163&partnerID=8YFLogxK
U2 - 10.3847/1538-4357/aaa95c
DO - 10.3847/1538-4357/aaa95c
M3 - Article
AN - SCOPUS:85042697163
SN - 0004-637X
VL - 854
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 124
ER -