Planets around the K-giants BD+20 274 and HD 219415

Gettel, S.; Wolszczan, A.; Niedzielski, A.; Nowak, G.; Adamów, M.; Zieliński, P.; Maciejewski, G.
Referencia bibliográfica

The Astrophysical Journal, Volume 756, Issue 1, article id. 53, 7 pp. (2012).

Fecha de publicación:
9
2012
Número de autores
7
Número de autores del IAC
0
Número de citas
15
Número de citas referidas
12
Descripción
We present the discovery of planet-mass companions to two giant stars by the ongoing Penn State-Toruń Planet Search conducted with the 9.2 m Hobby-Eberly Telescope. The less massive of these stars, K5-giant BD+20 274, has a 4.2 MJ minimum mass planet orbiting the star at a 578 day period and a more distant, likely stellar-mass companion. The best currently available model of the planet orbiting the K0-giant HD 219415 points to a >~ Jupiter-mass companion in a 5.7 year, eccentric orbit around the star, making it the longest period planet yet detected by our survey. This planet has an amplitude of ~18 m s-1, comparable to the median radial velocity "jitter," typical of giant stars.