SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT.VI. REVERBERATING DISK MODELS FOR NGC 5548

Journal
The Astrophysical Journal
ISSN
0004-637X
Date Issued
2017-01-18
DOI
WoS ID
WOS:000393455400065
Abstract
<jats:title>ABSTRACT</jats:title>
<jats:p>We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light curves (<jats:inline-formula>
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</jats:inline-formula>) combine simultaneous <jats:italic>Hubble Space Telescope</jats:italic>, <jats:italic>Swift</jats:italic>, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination <jats:inline-formula>
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</jats:inline-formula> K at 1 light day from the black hole, and a temperature–radius slope (<jats:inline-formula>
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</jats:inline-formula>. We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at <jats:inline-formula>
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OCDE Subjects

Natural sciences::Phy...

Author(s)
D. Starkey
Keith Horne
M. M. Fausnaugh
B. M. Peterson
M. C. Bentz
C. S. Kochanek
K. D. Denney
R. Edelson
M. R. Goad
G. De Rosa
M. D. Anderson
A. J. Barth
C. Bazhaw
G. A. Borman
T. A. Boroson
M. C. Bottorff
W. N. Brandt
A. A. Breeveld
E. M. Cackett
M. T. Carini
K. V. Croxall
D. M. Crenshaw
E. Dalla Bontà
A. De Lorenzo-Cáceres
M. Dietrich
N. V. Efimova
J. Ely
P. A. Evans
A. V. Filippenko
K. Flatland
N. Gehrels
S. Geier
J. M. Gelbord
L. Gonzalez
V. Gorjian
C. J. Grier
D. Grupe
P. B. Hall
S. Hicks
D. Horenstein
T. Hutchison
M. Im
J. J. Jensen
M. D. Joner
J. Jones
J. Kaastra
S. Kaspi
B. C. Kelly
J. A. Kennea
S. C. Kim
M. Kim
S. A. Klimanov
K. T. Korista
G. A. Kriss
J. C. Lee
D. C. Leonard
P. Lira
F. MacInnis
E. R. Manne-Nicholas
S. Mathur
I. M. McHardy
C. Montouri
R. Musso
S. V. Nazarov
R. P. Norris
J. A. Nousek
D. N. Okhmat
A. Pancoast
J. R. Parks
L. Pei
R. W. Pogge
J.-U. Pott
S. E. Rafter
H.-W. Rix
D. A. Saylor
J. S. Schimoia
K. Schnülle
S. G. Sergeev
M. H. Siegel
M. Spencer
H.-I. Sung
K. G. Teems
C. S. Turner
P. Uttley
M. Vestergaard
C. Villforth
Y. Weiss
J.-H. Woo
H. Yan
and S. Young
W. Zheng
Y. Zu