학술논문
Space Telescope and Optical Reverberation Mapping Project. VI. Reverberating Disk Models for NGS 5548
Document Type
Report
Author
Starkey, D; Gehrels, Cornelis; Horne, Keith; Fausnaugh, M. M; Peterson, B. M; Bentz, M. C; Kochanek, C. S; Denney, K. D; Edelson, R; Goad, M. R; De Rosa, G; Anderson, M. D; Arevalo, P; Barth, A. J; Bazhaw, C; Borman, G. A; Boroson, T. A; Bottorff, M. C; Brandt, W. N; Breeveld, A. A; Cackett E. M; Carini, M. T; Croxall, K. V; Crenshaw, D. M; Dalla Bonta, E; De Lorenzo-Caceres, A; Dietrich, M; Efimova, N. V; Ely, J; Evans, P. A; Filippenko, A. V; Flatland, I; Gehrels, N; Geier, S; Gelbord, J. M; Gonzalez, L; Gorjian, V; Grier, C. J; Grupe, D; Hall, P. B; Hicks, S; Horenstein, D; Hutchison, T; Im, M; Jensen, J. J; Joner, M. D; Jones, J; Kaastra, J; Kaspi, S; Kelly, B. C; Kennea, J. A; Kim, S. C; Kim, M; Kilmanov, S. A; Korista, K. T; Kriss, G. A; Lee, J. C; Leonard, D. C; Lira, P; MacInnis, F; Manne-Nicholas, E. R; Mathur, S; McHardy, I. M; Montouri, C; Musso, R; Nazarov, S. V; Norris, R. P; Nousek, J. A; Okhmat, D. N; Pancoast, A; Parks, J. R; Pei, L; Pogge, R. W; Pott, J.-U; Rafter, S. E; Rix, H.-W; Saylor, D. A; Schimoia, J. S; Schnuelle, K; Sergeev, S. G; Siegel, M. H; Spencer, M; Sung, H. I; Teems, K. G; Turner, C. S; Uttley, P; Vestergaard, M; Villforth, C; Weiss, Y; Woo, J.-H; Yan, H; Young, S; Zheng, W; Zu, Y
Source
The Astrophysical Journal. 835(1)
Subject
Language
English
ISSN
2041-8213
2041-8205
2041-8205
Abstract
We conduct a multi-wavelength 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 (1158 Angstrom to 9157 Angstrom) combine simultaneous Hubble Space Telescope, Swift, 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 i = 36deg +/- 10deg, temperature T(sub 1) = (44+/-6) times 10 (exp 3)K at 1 light day from the black hole, and a temperature radius slope (T proportional to r (exp -alpha)) of alpha = 0.99 +/- 0.03. 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 L/L(sub Edd) = 0.1.