A young and complex binary star – HD 144432

¹ Los Alamos National Laboratory, PO Box 1663, ISR-DO, Mail Stop F650, Los Alamos, NM 87545, USA
² Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 42, Cambridge, MA 02138, USA e-mail: mvandena@eso.org
³ TNO-TPD, Stieltjesweg 1, PO Box 155, 2600 AD Delft, The Netherlands e-mail: dolf@xiada.ft.uam.es
⁴ The University of Toledo, Dept. of Physics and Astronomy, Toledo, OH 43606, USA e-mail: bbopp@uoft02.utoledo.edu

Corresponding author: M. R. Pérez, mperez@lanl.gov

Received: 24 September 2003
Accepted: 17 November 2003

Abstract

The southern emission-line star HD 144432 has received considerable attention due to its relative brightness (), 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 an evolved (post-AGB) object and an isolated Herbig Ae/Be star. We confirm the presence of a faint companion source located 1.4´´ 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 Å absorption toward the HD 144432 system, and its apparent association with Sco OB2-2 located at 145 pc.