Papers

Kepler observations of V447 Lyr: an eclipsing U Gem Cataclysmic Variable

  1. Gavin Ramsay1,*,
  2. John K. Cannizzo2,3,
  3. Steve B. Howell4,
  4. Matt A. Wood5,
  5. Martin Still4,6,
  6. Thomas Barclay4,6,
  7. Alan Smale7

Article first published online: 8 AUG 2012

DOI: 10.1111/j.1365-2966.2012.21657.x

Issue

Monthly Notices of the Royal Astronomical Society

Monthly Notices of the Royal Astronomical Society

Volume 425, Issue 2, pages 1479–1485, 11 September 2012

Additional Information

How to Cite

Ramsay, G., Cannizzo, J. K., Howell, S. B., Wood, M. A., Still, M., Barclay, T. and Smale, A. (2012), Kepler observations of V447 Lyr: an eclipsing U Gem Cataclysmic Variable. Monthly Notices of the Royal Astronomical Society, 425: 1479–1485. doi: 10.1111/j.1365-2966.2012.21657.x

Author Information

  1. 1

    Armagh Observatory, Armagh

  2. 2

    CRESST and Astroparticle Physics Laboratory NASA/GSFC, Greenbelt, MD, USA

  3. 3

    Department of Physics, University of Maryland, Baltimore, MD, USA

  4. 4

    NASA Ames Research Center, CA, USA

  5. 5

    Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL, USA

  6. 6

    Bay Area Environmental Research Institute, Sonoma, CA, USA

  7. 7

    NASA/Goddard Space Flight Center, Greenbelt, MD, USA

*E-mail: gar@arm.ac.uk

Publication History

  1. Issue published online: 22 AUG 2012
  2. Article first published online: 8 AUG 2012
  3. Manuscript Accepted: 4 JUL 2012
  4. Manuscript Received: 3 JUL 2012

Funded by

  • NASA. Grant Number: NAG5-7584
  • Science Mission Directorate
  • National Science Foundation. Grant Number: AST 1109332

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (2368K)

Keywords:

  • accretion, accretion discs;
  • stars: dwarf novae;
  • stars: individual: V447 Lyr;
  • novae, cataclysmic variables

ABSTRACT

We present the results of an analysis of Kepler data covering 1.5 yr of the dwarf nova V447 Lyr. We detect eclipses of the accretion disc by the mass donating secondary star every 3.74 h which is the binary orbital period. V447 Lyr is therefore the first dwarf nova in the Kepler field to show eclipses. We also detect five long outbursts and six short outbursts showing V447 Lyr is a U Gem-type dwarf nova. We show that the orbital phase of the mid-eclipse occurs earlier during outbursts compared to quiescence and that the width of the eclipse is greater during outburst. This suggests that the bright spot is more prominent during quiescence and that the disc is larger during outburst than quiescence. This is consistent with an expansion of the outer disc radius due to the presence of high viscosity material associated with the outburst, followed by a contraction in quiescence due to the accretion of low angular momentum material. We note that the long outbursts appear to be triggered by a short outburst, which is also observed in the super-outbursts of SU UMa dwarf novae as observed using Kepler.

View Full Article (HTML) Get PDF (2368K)