Friday, June 22, 2012

1206.4938 (M. Adamów et al.)

BD+48 740 - Li overabundant giant star with a planet. A case of recent engulfment?    [PDF]

M. Adamów, A. Niedzielski, E. Villaver, G. Nowak, A. Wolszczan
We report the discovery of a unique object, BD+48 740, a lithium overabundant giant with A(Li)=2.33 +/- 0.04 (where A(Li) = log(n_Li/n_H) + 12), that exhibits radial velocity (RV) variations consistent with a 1.6 M_J companion in a highly eccentric, e = 0.67 +/- 0.17 and extended, a=1.89 AU (P=771 d), orbit. The high eccentricity of the planet is uncommon among planetary systems orbiting evolved stars and so is the high lithium abundance in a giant star. The ingestion by the star of a putative second planet in the system originally in a closer orbit, could possibly allow for a single explanation to these two exceptional facts. If the planet candidate is confirmed by future RV observations, it might represent the first example of the remnant of a multiple planetary system possibly affected by stellar evolution.
View original: http://arxiv.org/abs/1206.4938

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