SUBSTELLAR-MASS COMPANIONS TO THE K-GIANTS HD 240237, BD +48 738, AND HD 96127

Journal Article · Fri Jan 20 04:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/745/1/28· OSTI ID:22011991

Gettel, S; Wolszczan, A ^[1]; Niedzielski, A; Nowak, G; Adamow, M; Zielinski, P; Maciejewski, G ^[2]

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1. Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States)
2. Torun Center for Astronomy, Nicolaus Copernicus University, ul. Gagarina 11, 87-100 Torun (Poland)

We present the discovery of substellar-mass companions to three giant stars by the ongoing Penn State-Torun Planet Search conducted with the 9.2 m Hobby-Eberly Telescope. The most massive of the three stars, K2-giant HD 240237, has a 5.3 M{sub J} minimum mass companion orbiting the star at a 746 day period. The K0-giant BD +48 738 is orbited by a {>=}0.91 M{sub J} planet which has a period of 393 days and shows a nonlinear, long-term radial velocity (RV) trend that indicates a presence of another, more distant companion, which may have a substellar mass or be a low-mass star. The K2-giant HD 96127 has a {>=}4.0 M{sub J} mass companion in a 647 day orbit around the star. The two K2-giants exhibit a significant RV noise that complicates the detection of low-amplitude, periodic variations in the data. If the noise component of the observed RV variations is due to solar-type oscillations, we show, using all the published data for the substellar companions to giants, that its amplitude is anti-correlated with stellar metallicity.

• OSTI ID: 22011991
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 745; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
GIANT STARS
MASS
NONLINEAR PROBLEMS
ORBITS
PERIODICITY
PLANETS
RADIAL VELOCITY
TELESCOPES