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arXiv · 1210.3055

Two possible circumbinary planets in the eclipsing post-common envelope system NSVS 14256825

L. A. Almeida·F. Jablonski·C. V. Rodrigues
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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 July, 2010 and August, 2012. 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 P_c ~ 3.5 years and P_d ~ 6.9 years. The corresponding projected semi-major axes would be a_c i_c ~ 1.9 AU and a_d i_d ~ 2.9 AU. The masses of the external bodies would be M_c ~ 2.9 M_{Jupiter} and M_d ~ 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.

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L. A. Almeida, F. Jablonski, C. V. Rodrigues. 2012-10-10. Two possible circumbinary planets in the eclipsing post-common envelope system NSVS 14256825. https://doi.org/10.1088/0004-637x%2F766%2F1%2F11

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