2004/06/24 by D. Baines, R. D. Oudmaijer, A. Mora +18 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astrophysics and Star Formation Studies #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2004.08104.x
MNRAS in press 8 pages 7 figures
arxiv created 2004/06/24 · openalex publication_date 2004/09/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this paper we present multi-epoch observations of the pre-main-sequence binary HK Ori. These data have been drawn from the EXPORT data base and are complemented by high-quality spectro-astrometric data of the system. The spectroscopic data appear to be very well represented by a combination of an A dwarf star spectrum superposed on a (sub)giant G-type spectrum. The radial velocity of the system is consistent with previous determinations, and does not reveal binary motion, as expected for a wide binary. The spectral, photometric and polarimetric properties and variability of the system indicate that the active object in the system is a T Tauri star with UX Ori characteristics. The spectro-astrometry of HK Ori is sensitive down to milliarcsecond scales and confirms the speckle interferometric results from Leinert et al. The spectro-astrometry allows the identification, with fair certainty, of the active star within the binary, which we suggest to be a G-type T Tauri star based on its spectral characteristics.