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  • Author(s): Barth, Aaron J
  • Nguyen, My L
  • Malkan, Matthew A
  • Filippenko, Alexei V
  • Li, Weidong
  • Gorjian, Varoujan
  • Joner, Michael D
  • Bennert, Vardha Nicola
  • Botyanszki, Janos
  • Cenko, S Bradley
  • Childress, Michael
  • Choi, Jieun
  • Comerford, Julia M
  • Cucciara, Antonino
  • da Silva, Robert
  • Duchêne, Gaspard
  • Fumagalli, Michele
  • Ganeshalingam, Mohan
  • Gates, Elinor L
  • Gerke, Brian F
  • Griffith, Christopher V
  • Harris, Chelsea
  • Hintz, Eric G
  • Hsiao, Eric
  • Kandrashoff, Michael T
  • Keel, William C
  • Kirkman, David
  • Kleiser, Io KW
  • Laney, C David
  • Lee, Jeffrey
  • Lopez, Liliana
  • Lowe, Thomas B
  • Moody, J Ward
  • Morton, Alekzandir
  • Nierenberg, AM
  • Nugent, Peter
  • Pancoast, Anna
  • Rex, Jacob
  • Rich, R Michael
  • Silverman, Jeffrey M
  • Smith, Graeme H
  • Sonnenfeld, Alessandro
  • Suzuki, Nao
  • Tytler, David
  • Walsh, Jonelle L
  • Woo, Jong-Hak
  • Yang, Yizhe
  • Zeisse, Carl
  • et al.

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. © 2011. The American Astronomical Society. All rights reserved.

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