Two Possible Circumbinary Planets in the Eclipsing Post-common Envelope System NSVS 14256825
Abstract
We present an analysis of eclipse timings of the post-common envelope binary NSVS 14256825, which is composed of an sdOB star and a dM star in a close orbit (P orb = 0.110374 days). High-speed photometry of this system was performed between 2010 July and 2012 August. Ten new mid-eclipse times were analyzed together with all available eclipse times in the literature. We revisited the (O - C) diagram using a linear ephemeris and verified a clear orbital period variation. On the assumption that these orbital period variations are caused by light travel time effects, the (O - C) diagram can be explained by the presence of two circumbinary bodies, even though this explanation requires a longer baseline of observations to be fully tested. The orbital periods of the best solution would be Pc ~ 3.5 years and Pd ~ 6.9 years. The corresponding projected semi-major axes would be ac sin ic ~ 1.9 AU and ad sin id ~ 2.9 AU. The masses of the external bodies would be Mc ~ 2.9 M Jupiter and Md ~ 8.1 M Jupiter, if we assume their orbits are coplanar with the close binary. Therefore NSVS 14256825 might be composed of a close binary with two circumbinary planets, though the orbital period variations is still open to other interpretations.
Based on observations carried out at the Observatório do Pico dos Dias (OPD/LNA) in Brazil.- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 2013
- DOI:
- 10.1088/0004-637X/766/1/11
- arXiv:
- arXiv:1210.3055
- Bibcode:
- 2013ApJ...766...11A
- Keywords:
-
- binaries: close;
- binaries: eclipsing;
- planetary systems;
- stars: individual: NSVS 14256825;
- subdwarfs;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 16 pages, 3 figures, 4 tables. Accepted for publication in ApJ