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Multiple Companions to HD 154857 and HD 160691

Chris McCarthy·R. Paul Butler·C. G. Tinney·Hugh R. A. Jones·Geoffrey W. Marcy·Brad Carter·Alan J. Penny·Debra A. Fischer
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Abstract

Precise Doppler measurements from the AAT/UCLES spectrometer reveal two companions to both HD 154857 and HD 160691. The inner companion to HD 154857 has a period of 398 d, an eccentricity of 0.51, and a minimum mass of 1.8 M_Jupiter An outer companion has a period much longer than 2 years and is currently detected only as a linear trend of 14 m/s per year. The inner companion to HD 160691, previously announced from AAT data, has a period of 645 d, an eccentricity of 0.20, and a minimum mass of 1.7 M_Jupiter. For the outer planet, whose orbit is less well constrained, a two Keplerian fit yields a period of 8.2 yr, an eccentricity of 0.57, and a minimum mass of 3.1 M_Jupiter. With these orbital parameters, its maximum separation from the star of 0.4 arcsec makes it a viable target for direct imaging.

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Chris McCarthy, R. Paul Butler, C. G. Tinney, Hugh R. A. Jones, Geoffrey W. Marcy, Brad Carter, Alan J. Penny, Debra A. Fischer. 2004-09-14. Multiple Companions to HD 154857 and HD 160691. https://doi.org/10.1086/425214

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