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The pre-main sequence binary HK Ori : Spectro-astrometry and EXPORT data

D. Baines·R. D. Oudmaijer·A. Mora·C. Eiroa·the EXPORT collaboration
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Abstract

In this paper we present multi-epoch observations of the pre-main sequence binary HK Ori. These data have been drawn from the EXPORT database 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 milli-arcsecond scales and confirms the speckle interferometric results from Leinert et al. The spectro-astrometry allows with fair certainty the identification of the active star within the binary, which we suggest to be a G-type T Tauri star based on its spectral characteristics.

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D. Baines, R. D. Oudmaijer, A. Mora, C. Eiroa, the EXPORT collaboration. 2004-06-24. The pre-main sequence binary HK Ori : Spectro-astrometry and EXPORT data. https://doi.org/10.1111/j.1365-2966.2004.08104.x

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