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Space Telescope and Optical Reverberation Mapping Project. IX. Velocity–Delay Maps for Broad Emission Lines in NGC 5548

Horne, Keith and Rosa, G. De and Peterson, B. M. and Barth, A. J. and Ely, J. and Fausnaugh, M. M. and Kriss, G. A. and Pei, L. and Bentz, M. C. and Cackett, E. M. and Edelson, R. and Eracleous, M. and Goad, M. R. and Grier, C. J. and Kaastra, J. and Kochanek, C. S. and Krongold, Y. and Mathur, S. and Netzer, H. and Proga, D. and Tejos, N. and Vestergaard, M. and Villforth, C. and Adams, S. M. and Anderson, M. D. and Arévalo, P. and Beatty, T G. and Bennert, V. N. and Bigley, A. and Bisogni, S. and Borman, G. A. and Boroson, T. A. and Bottorff, M. C. and Brandt, W. N. and Breeveld, A. A. and Brotherton, M. and Brown, J. E. and Brown, J. S. and Canalizo, G. and Carini, M. T. and Clubb, K. I. and Comerford, J. M. and Corsini, E. M. and Crenshaw, D. M. and Croft, S. and Croxall, K. V. and Bontà, E. Dalla and Deason, A. J. and Dehghanian, M. and De Lorenzo-Cáceres, A. and Denney, K. D. and Dietrich, M. and Done, C. and Efimova, N. V. and Evans, P. A. and Ferland, G. J. and Filippenko, A. V. and Flatland, K. and Fox, O. D. and Gardner, E. and Gates, E. L. and Gehrels, N. and Geier, S. and Gelbord, J. M. and Gonzalez, L. and Gorjian, V. and Greene, J. E. and Grupe, D. and Gupta, A. and Hall, P. B. and Henderson, C. B. and Hicks, S. and Holmbeck, E. and Holoien, T. W.-S. and Hutchison, T. and Im, M. and Jensen, J. J. and Johnson, C. A. and Joner, M. D. and Jones, J. and Kaspi, S. and Kelly, P. L. and Kennea, J. A. and Kim, M. and Kim, S. and Kim, S. C. and King, A. and Klimanov, S. A. and Korista, K. T. and Lau, M. W. and Lee, J. C. and Leonard, D. C. and Li, Miao and Lira, P. and Lochhaas, C. and Ma, Zhiyuan and MacInnis, F. and Malkan, M. A. and Manne-Nicholas, E. R. and Mauerhan, J. C. and McGurk, R. and McHardy, I. M. and Montuori, C. and Morelli, L. and Mosquera, A. and Mudd, D. and Müller–Sánchez, F. and Nazarov, S. V. and Norris, R. P. and Nousek, J. A. and Nguyen, M. L. and Ochner, P. and Okhmat, D. N. and Pancoast, A. and Papadakis, I. and Parks, J. R. and Penny, M. T. and Pizzella, A. and Pogge, R. W. and Poleski, R. and Pott, J.-U. and Rafter, S. E. and Rix, H.-W. and Runnoe, J. and Saylor, D. A. and Schimoia, J. S. and Schnülle, K. and Scott, B. and Sergeev, S. G. and Shappee, B. J. and Shivvers, I. and Siegel, M. and Simonian, G. V. and Siviero, A. and Skielboe, A. and Somers, G. and Spencer, M. and Starkey, D. and Stevens, D. J. and Sung, H.-I. and Tayar, J. and Treu, T. and Turner, C. S. and Uttley, P. and Van Saders, J. and Vican, L. and Villanueva, S. and Weiss, Y. and Woo, J.-H. and Yan, H. and Young, S. and Yuk, H. and Zheng, W. and Zhu, W. and Zu, Y. (2021) Space Telescope and Optical Reverberation Mapping Project. IX. Velocity–Delay Maps for Broad Emission Lines in NGC 5548. Astrophysical Journal, 907 (2). Art. No. 76. ISSN 1538-4357.

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In this contribution, we achieve the primary goal of the active galactic nucleus (AGN) STORM campaign by recovering velocity–delay maps for the prominent broad emission lines (Lyα, C IV, He II, and Hβ) in the spectrum of NGC 5548. These are the most detailed velocity–delay maps ever obtained for an AGN, providing unprecedented information on the geometry, ionization structure, and kinematics of the broad-line region. Virial envelopes enclosing the emission-line responses show that the reverberating gas is bound to the black hole. A stratified ionization structure is evident. The He II response inside 5–10 lt-day has a broad single-peaked velocity profile. The Lyα, C IV, and Hβ responses extend from inside 2 to outside 20 lt-day, with double peaks at ±2500 km s⁻¹ in the 10–20 lt-day delay range. An incomplete ellipse in the velocity–delay plane is evident in Hβ. We interpret the maps in terms of a Keplerian disk with a well-defined outer rim at R = 20 lt-day. The far-side response is weaker than that from the near side. The line-center delay τ = (R/c)(1-sin i) ≈ 5 days gives the inclination i ≈ 45°. The inferred black hole mass is M_(BH) ≈ 7 × 10⁷ M_⊙. In addition to reverberations, the fit residuals confirm that emission-line fluxes are depressed during the "BLR Holiday" identified in previous work. Moreover, a helical "Barber-Pole" pattern, with stripes moving from red to blue across the C IV and Lyα line profiles, suggests azimuthal structure rotating with a 2 yr period that may represent precession or orbital motion of inner-disk structures casting shadows on the emission-line region farther out.

Item Type:Article
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URLURL TypeDescription Paper
Horne, Keith0000-0003-1728-0304
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Lochhaas, C.0000-0003-1785-8022
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Malkan, M. A.0000-0001-6919-1237
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McGurk, R.0000-0003-2064-4105
Morelli, L.0000-0001-6890-3503
Nousek, J. A.0000-0001-7084-4637
Pancoast, A.0000-0003-1065-5046
Penny, M. T.0000-0001-7506-5640
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Poleski, R.0000-0002-9245-6368
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Rix, H.-W.0000-0003-4996-9069
Runnoe, J.0000-0001-8557-2822
Saylor, D. A.0000-0002-0558-1305
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Woo, J.-H.0000-0002-8055-5465
Yan, H.0000-0001-7592-7714
Zu, Y.0000-0001-6966-6925
Additional Information:© 2021 The American Astronomical Society. Received 2020 September 20; revised 2020 November 12; accepted 2020 November 25; published 2021 February 1. Support for HST program No. GO-13330 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. K.H. acknowledges support from STFC grant ST/R000824/1. G.D.R., B.M.P., M.M.F, C.J.G., and R.W.P. are grateful for the support of the National Science Foundation (NSF) through grant AST-1008882 to The Ohio State University. Research at UC Irvine has been supported by NSF grants AST-1412693 and AST-1907290. M.C. Bentz gratefully acknowledges support through NSF CAREER grant AST-1253702 to Georgia State University. V.N.B. gratefully acknowledges assistance from National Science Foundation (NSF) Research at Undergraduate Institutions (RUI) grant AST-1909297. S.B. is supported by NASA through Chandra award AR7-18013X issued by the Chandra X-ray Observatory Center, operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8-03060. S.B. was also partially supported by grant HST-AR-13240.009. M.C. Bottorff acknowledges HHMI for support through an undergraduate science education grant to Southwestern University. E.M.C., E.D.B., L.M., and A.P. acknowledge support from Padua University through grants DOR1699945/16, DOR1715817/17, DOR1885254/18, and BIRD164402/16. G.F. and M. Dehghanian acknowledge support from the NSF (AST-1816537), NASA (ATP 17-0141), and STScI (HST-AR-13914, HST-AR-15018), and the Huffaker Scholarship. K.D.D. is supported by an NSF Fellowship awarded under grant AST-1302093. R.E. gratefully acknowledges support from NASA under ADAP award 80NSSC17K0126. P.A.E. acknowledges UKSA support. Support for A.V.F.'s group at UC Berkeley is provided by NSF grant AST-1211916, the TABASGO Foundation, the Christopher R. Redlich Fund, and the Miller Institute for Basic Research in Science. J.M.G. gratefully acknowledges support from NASA under awards NNX15AH49G and 80NSSC17K0126. P.B.H. is supported by NSERC. M.I. acknowledges support from the National Research Foundation of Korea (NRF) grant, No. 2020R1A2C3011091. M.D.J. acknowledges NSF grant AST-0618209. M.K. was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2017R1C1B2002879). SRON is financially supported by NWO, the Netherlands Organization for Scientific Research. C.S.K. is supported by NSF grants AST-1515876 and AST-1814440. Y.K. acknowledges support from DGAPA-PAIIPIT grant IN106518. D.C.L. acknowledges support from NSF grants AST-1009571 and AST-1210311. P.L. acknowledges support from Fondecyt grant 1120328. A.P. is supported by NASA through Einstein Postdoctoral Fellowship grant No. PF5-160141 awarded by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060. J.S.S. acknowledges CNPq, National Council for Scientific and Technological Development (Brazil) for partial support and The Ohio State University for warm hospitality. T.T. has been supported by NSF grant AST-1412315. T.T. and B.C.K. acknowledge support from the Packard Foundation in the form of a Packard Research Fellowship to T.T. The American Academy in Rome and the Observatory of Monteporzio Catone are thanked by T.T. for kind hospitality. M.V. gratefully acknowledges support from the Independent Research Fund Denmark via grant Nos. DFF 4002-00275 and 8021-00130. J.-H.W. acknowledges support by the National Research Foundation of Korea (NRF) grant funded by the Korean government (No. 2010-0027910). 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. Research at Lick Observatory is partially supported by a generous gift from Google.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Science and Technology Facilities Council (STFC)ST/R000824/1
NASA Hubble FellowshipHST-AR-13240.009
Southwestern UniversityUNSPECIFIED
Padua UniversityDOR1699945/16
Padua UniversityDOR1715817/17
Padua UniversityDOR1885254/18
Padua UniversityBIRD164402/16
NASAATP 17-0141
NASA Hubble FellowshipHST-AR-13914
NASA Hubble FellowshipHST-AR-15018
Huffaker ScholarshipUNSPECIFIED
United Kingdom Space Agency (UKSA)UNSPECIFIED
Christopher R. Redlich FundUNSPECIFIED
Miller Institute for Basic Research in ScienceUNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
National Research Foundation of Korea2020R1A2C3011091
National Research Foundation of Korea2017R1C1B2002879
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)UNSPECIFIED
Dirección General de Asuntos del Personal Académico (DGAPA)IN106518
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)1120328
NASA Einstein FellowshipPF5-160141
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)UNSPECIFIED
David and Lucile Packard FoundationUNSPECIFIED
Danish Council for Independent ResearchDFF 4002-00275
Danish Council for Independent ResearchDFF 8021-00130
National Research Foundation of Korea2010-0027910
Subject Keywords:Active galaxies ; Astrophysical black holes ; Supermassive black holes ; Active galactic nuclei ; Reverberation mapping
Issue or Number:2
Classification Code:Unified Astronomy Thesaurus concepts: Active galaxies (17); Astrophysical black holes (98); Supermassive black holes (1663); Active galactic nuclei (16); Reverberation mapping (2019)
Record Number:CaltechAUTHORS:20210201-130033519
Persistent URL:
Official Citation:Keith Horne et al 2021 ApJ 907 76
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:107838
Deposited By: Tony Diaz
Deposited On:01 Feb 2021 21:45
Last Modified:01 Feb 2021 21:45

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