2009/08/24 by K. G. Hełminiak, K. G. He��miniak, M. Konacki +2 · 2 citations
Physics and Astronomy · #Adaptive optics #Adaptive optics and wavefront sensing #Astrometry #Astronomy and Astrophysical Research #Binary number #Binary star #Exoplanet #Sample (material) #Speckle imaging #Speckle pattern #Stars #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1111/j.1365-2966.2009.15495.x
18 pages, 8 figures, 9 tables, to appear in MNRAS
arxiv created 2009/08/24 · openalex publication_date 2009/09/22 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Using the adaptive optics facilities at the 200-in Hale and 10-m Keck II, we observed in the near-infrared a sample of 12 binary and multiple stars and one open cluster. We used the near diffraction limited images of these systems to measure the relative separations and position angles between their components. In this paper, we investigate and correct for the influence of the differential chromatic refraction and chip distortions on our relative astrometric measurements. Over one night, we achieve an astrometric precision typically well below 1 mas and occasionally as small as 40 μas. Such a precision is in principle sufficient to astrometrically detect planetary mass objects around the components of nearby binary and multiple stars. Since we have not had sufficiently large data sets for the observed sample of stars to detect planets, we provide the limits to planetary mass objects based on the obtained astrometric precision.