A circumbinary planet in orbit around the short-period white dwarf eclipsing binary RR Cae

  1. S.-B. Qian1,2,3,*,
  2. L. Liu1,2,3,
  3. L.-Y. Zhu1,2,
  4. Z.-B. Dai1,2,
  5. E. Fernández Lajús4,5,
  6. G. L. Baume4,5

Article first published online: 29 FEB 2012

DOI: 10.1111/j.1745-3933.2012.01228.x

Issue

Monthly Notices of the Royal Astronomical Society: Letters

Monthly Notices of the Royal Astronomical Society: Letters

Volume 422, Issue 1, pages L24–L27, May 2012

Additional Information

How to Cite

Qian, S.-B., Liu, L., Zhu, L.-Y., Dai, Z.-B., Fernández Lajús, E. and Baume, G. L. (2012), A circumbinary planet in orbit around the short-period white dwarf eclipsing binary RR Cae. Monthly Notices of the Royal Astronomical Society: Letters, 422: L24–L27. doi: 10.1111/j.1745-3933.2012.01228.x

Author Information

  1. 1

    National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, PO Box 110, 650011 Kunming, China

  2. 2

    Key Laboratory of the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, PO Box 110, 650011 Kunming, China

  3. 3

    Graduate University of the Chinese Academy of Sciences, 19A Yuquanlu, Sijingshang Block, 100049 Beijing, China

  4. 4

    Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, 1900 La Plata, Buenos Aires, Argentina

  5. 5

    Instituto de Astrofisica de La Plata (CCT La Plata – CONICET/UNLP), Paseo del Bosque s/n, La Plata, BA, B1900FWA, Argentina

* E-mail: qsb@ynao.ac.cn

Publication History

  1. Issue published online: 19 APR 2012
  2. Article first published online: 29 FEB 2012
  3. Accepted 2012 January 24. Received 2012 January 24; in original form 2011 December 20

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

View Full Article (HTML) Get PDF (533K)

Keywords:

  • binaries: close;
  • binaries: eclipsing;
  • stars: individual: RR Cae;
  • planetary systems;
  • white dwarfs

ABSTRACT

By using six newly determined mid-eclipse times together with those collected from the literature, we have found that the observed minus calculated (O−C) curve of RR Cae shows a cyclic change with a period of 11.9 yr and an amplitude of 14.3 s while it undergoes an upward parabolic variation [revealing a long-term period increase at a rate of inline image]. The cyclic change was analysed for the light-travel-time effect that arises from the gravitational influence of a third companion. The mass of the third body was determined to be M3sin i′= 4.2(± 0.4) MJup, suggesting that it is a circumbinary giant planet when its orbital inclination is larger than 17bsl000646. The orbital separation of the circumbinary planet from the central eclipsing binary is about 5.3(± 0.6) au. The period increase is opposite to the changes caused by angular momentum loss via magnetic braking or/and gravitational radiation; and it cannot be explained by the mass transfer between both components because of its detached configuration. These indicate that the observed upward parabolic change is only a part of a long-period (longer than 26.3 yr) cyclic variation, which may reveal the presence of another giant circumbinary planet in a wide orbit.

View Full Article (HTML) Get PDF (533K)