BD+48 740—Li OVERABUNDANT GIANT STAR WITH A PLANET: A CASE OF RECENT ENGULFMENT?

M. Adamów, A. Niedzielski, E. Villaver, G. Nowak, A. Wolszczan
2012 Astrophysical Journal Letters  
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
more » ... 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.
doi:10.1088/2041-8205/754/1/l15 fatcat:g4edu4vjunhr5cj7k46f5dvno4