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arXiv · 1207.0488

Planets Around the K-Giants BD+20 274 and HD 219415

S. Gettel·A. Wolszczan·A. Niedzielski·G. Nowak·M. Adamów·P. Zieliński·G. Maciejewski
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Abstract

We present the discovery of planet-mass companions to two giant stars by the ongoing Penn State- Toru\'n Planet Search (PTPS) 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 \sim18 m/s, comparable to the median radial velocity (RV) "jitter", typical of giant stars.

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S. Gettel, A. Wolszczan, A. Niedzielski, G. Nowak, M. Adamów, P. Zieliński, G. Maciejewski. 2012-07-02. Planets Around the K-Giants BD+20 274 and HD 219415. https://doi.org/10.1088/0004-637x/756/1/53

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