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arXiv · astro-ph/0312119

A young and complex binary star - HD 144432

M. R. Pérez·M. E. van den Ancker·D. de Winter·B. W. Bopp
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Abstract

The southern emission-line star HD 144432 has received considerable attention due to its relative brightness (V ~ 8.17), its late spectral type (late A-type or perhaps early F) and its relative isolation from a bona-fide active star formation region. We present new imaging and spectroscopic data of this star, which in the past has been classified as both evolved (post-AGB) object and an isolated Herbig Ae/Be star. We confirm the presence of a faint companion source located 1.4 arcseconds north, which appears physically associated with HD 144432. New infrared spectroscopy reveals this companion to be a late-type (early-mid K) star, devoid of any emission lines. Furthermore, we confirm the pre-main sequence nature of this object, report the detection of Li I 6707.8 AA absorption toward the HD 144432 system, and its apparent association with Sco OB2-2 located at 145 pc.

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M. R. Pérez, M. E. van den Ancker, D. de Winter, B. W. Bopp. 2003-12-04. A young and complex binary star - HD 144432. https://doi.org/10.1051/0004-6361%3A20034390

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