Astrophysics, abstract
astro-ph/0612214

From: David Weldrake [view email]

Date: Fri, 8 Dec 2006 12:42:02 GMT (51kb)

Radial Velocity Follow-up of Planetary Transit Candidate MACHO.120.22303.5389

Authors: David T.F Weldrake, Johny Setiawan, Patrick Weise, Thomas Henning

Comments: 3 pages, 2 figures. To appear in the PASP proceedings of "Transiting Extrasolar Planets Workshop" MPIA Heidelberg Germany, 25th-28th September 2006. Eds: Cristina Afonso, David Weldrake & Thomas Henning

We present preliminary results on the radial velocity follow-up of a planetary transit candidate (P=2.43d, V=15.4) detected during the MACHO project. The photometry is consistent with a grazing transit of an object with radius >=1.8RJ orbiting a K dwarf star, and is the brightest best candidate detected from MACHO. Results from the 2.2m MPG/ESO telescope and FEROS (R=48,000) in May 2006 display an apparent radial velocity variation with amplitude ~650m/s with the same period as the transit, and a solar-type primary. This is consistent with an orbiting companion of mass ~4MJ. However, further observations display an additional secondary long-period variation with amplitude of several km/s, indicating the presence of a third body. The system is likely a low mass eclipsing binary orbiting the solar-type primary. Further observations are planned to fully characterize the system.

http://arxiv.org/abs/astro-ph/0612214