We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham Research Online
You are in:

Broad-line reverberation in the Kepler-field Seyfert galaxy Zw 229-015.

Barth, A.J. and Nguyen, M.L. and Malkan, M.A. and Filippenko, A.V. and Li, W. and Gorjian, V. and Joner, M.D. and Bennert, V.N. and Botyanszki, J. and Cenko, S.B. and Childress, M. and Choi, J. and Comerford, J.M. and Cucciara, A. and da Silva, R. and Duchêne, G. and Fumagalli, M. and Ganeshalingam, M. and Gates, E.L. and Gerke, B.F. and Griffith, C.V. and Harris, C. and Hintz, E.G. and Hsiao, E. and Kandrashoff, M.T. and Keel, W.C. and Kirkman, D. and Kleiser, I.K.W. and Laney, C.D. and Lee, J. and Lopez, L. and Lowe, T.B. and Moody, J.W. and Morton, A. and Nierenberg, A.M. and Nugent, P. and Pancoast, A. and Rex, J. and Rich, R.M. and Silverman, J.M. and Smith, G.H. and Sonnenfeld, A. and Suzuki, N. and Tytler, D. and Walsh, J.L. and Woo, J.-H. and Yang, Y. and Zeisse, C. (2011) 'Broad-line reverberation in the Kepler-field Seyfert galaxy Zw 229-015.', Astrophysical journal., 732 (2). p. 121.


The Seyfert 1 galaxy Zw 229-015 is among the brightest active galaxies being monitored by the Kepler mission. In order to determine the black hole mass in Zw 229-015 from Hβ reverberation mapping, we have carried out nightly observations with the Kast Spectrograph at the Lick 3 m telescope during the dark runs from 2010 June through December, obtaining 54 spectroscopic observations in total. We have also obtained nightly V-band imaging with the Katzman Automatic Imaging Telescope at Lick Observatory and with the 0.9 m telescope at the Brigham Young University West Mountain Observatory over the same period. We detect strong variability in the source, which exhibited more than a factor of two change in broad Hβ flux. From cross-correlation measurements, we find that the Hβ light curve has a rest-frame lag of 3.86+0.69 –0.90 days with respect to the V-band continuum variations. We also measure reverberation lags for Hα and Hγ and find an upper limit to the Hδ lag. Combining the Hβ lag measurement with a broad Hβ width of σline = 1590 ± 47 km s–1 measured from the rms variability spectrum, we obtain a virial estimate of M BH = 1.00+0.19 –0.24 × 107 M ☉ for the black hole in Zw 229-015. As a Kepler target, Zw 229-015 will eventually have one of the highest-quality optical light curves ever measured for any active galaxy, and the black hole mass determined from reverberation mapping will serve as a benchmark for testing relationships between black hole mass and continuum variability characteristics in active galactic nuclei.

Item Type:Article
Full text:(VoR) Version of Record
Download PDF
Publisher Web site:
Publisher statement:© 2011. The American Astronomical Society. All rights reserved.
Date accepted:10 March 2011
Date deposited:20 April 2016
Date of first online publication:May 2011
Date first made open access:No date available

Save or Share this output

Look up in GoogleScholar