Multiple Companions to HD 154857 and HD 160691
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 MJupiter 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 MJupiter. 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 MJupiter. With these orbital parameters, its maximum separation from the star of 0.4 arcsec makes it a viable target for direct imaging.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.