Two circumbinary brown dwarfs at V470 Cam

Accepted manuscript

Eclipse Time Variations in the Post-Common Envelope Binary V470 Cam

Quote :

Linear or quadratic relations fitted to the time-dependence of post-common envelope binary eclipse times generally give residuals exhibiting a cyclic variation. Among several possible explanations is the presence of one or more orbiting circumbinary objects causing a reflex motion of the binary centre-of-mass, thereby altering the light-travel-time. Twenty new eclipse times for the post-common envelope binary V470 Cam have been obtained; with these and 380 useable eclipse times in the literature, two circumbinary brown dwarfs having orbital periods of 7.87 ± 0.08 and 13.27 ± 0.16 years were found to give an excellent fit to cyclic residuals resulting from a quadratic ephemeris fit. Irrespective of the excellent fit, it would be premature to claim that the V470 Cam binary is accompanied by two orbiting brown dwarfs; at the very least more eclipse times are needed to confirm the result and other plausible explanations, such as the Applegate mechanism, need eliminating.

No full text or eprint available yet.

P.S. aka HS 0705+6700.

*update*

Now featuring at EPE

http://exoplanet.eu/catalog/v470_cam_(ab)_b/
http://exoplanet.eu/catalog/v470_cam_(ab)_c/