2005/01/31 by T. Verhoelst, Tijl Verhoelst, P. J. Bordé +14 · 7 citations
Engineering · Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomical Observations and Instrumentation #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1051/0004-6361:20042356
15 pages, 14 figures, accepted for publication by Astronomy & Astrophysics
arxiv created 2005/01/31 · openalex publication_date 2005/04/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
We present near-IR interferometric measurements of the K1.5 giant Arcturus (α Bootis), obtained at the IOTA interferometer with the FLUOR instrument, in four narrow filters with central wavelengths ranging from 2.03 μm to 2.39 μm. These observations were expected to allow us to quantify the wavelength dependence of the diameter of a typical K giant. They are compared to predictions from both plane-parallel and spherical model atmospheres. Unexpectedly, neither can explain the observed visibilities. We show that these data suggest the presence of a companion, in accordance with the Hipparcos data on this star, and discuss this solution with respect to Arcturus' single star status.