2010/07/02 by Deepak Raghavan, Harold A. McAlister, Todd J. Henry +6 · 19 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #Binary number #Binary star #Multiplicity (mathematics) #Planet #Space Technology and Applications #Speckle pattern #Stars #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1088/0067-0049/190/1/1
Accepted for publication by the ApJS. 182 pages, including 24 figures and 18 tables. The Abstract on astro-ph has been trimmed to adhere to character-limits. Please see the PDF for the full abstract
arxiv created 2010/07/02 · openalex publication_date 2010/08/13 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We present the results of a comprehensive assessment of companions to solar-type stars. A sample of 454 stars, including the Sun, was selected from the Hipparcos catalog with π > 40 mas, σπ/π < 0.05, 0.5 < B - V < 1.0 (~ F6-K3), and constrained by absolute magnitude and color to exclude evolved stars. New observational aspects of this work include surveys for (1) very close companions with long-baseline interferometry at the CHARA Array, (2) close companions with speckle interferometry, and (3) wide proper motion companions identified by blinking multi-epoch archival images. In addition, we include the results from extensive radial-velocity monitoring programs and evaluate companion information from various catalogs. The overall observed fractions of single, double, triple, and higher order systems are 56% ± 2%, 33% ± 2%, 8% ± 1%, and 3% ± 1%, respectively, counting all confirmed stellar and brown dwarf companions. Our completeness analysis indicates that only a few undiscovered companions remain in this well-studied sample, implying that the majority (54% ± 2%) of solar-type stars are single, in contrast to the results of prior multiplicity studies. The orbital-period distribution of companions is unimodal and roughly log-normal with a peak of about 300 years. The period-eccentricity relation shows a roughly flat distribution beyond the expected circularization for periods below 12 days. The mass-ratio distribution shows a preference for like-mass pairs, which occur more frequently in relatively close pairs. The fraction of planet hosts among single, binary, and multiple systems are statistically indistinguishable, suggesting that planets are as likely to form around single stars as they are around components of binary or multiple systems with sufficiently wide separations.