Spectroscopic variability in giant and supergiant massive stars

HIGA, R.; FERRERO, G.; GAMEN, R.

Buenos Aires

Congreso; Reunión Anual de la Asociación Argentina de Astronomía; 2022

IAFE (CONICET-UBA)

Massive stars (MZAMS ≳ 8 M⊙) are among the most challenging and important astronomical objects. However, their main characteristics are still poorly known. This scant knowledge is particularly limited among giants and supergiants. The OWN Survey has detected variations of undetermined origin in the spectra of several giant and supergiant O-stars. We are conducting an intensive observational study of a sample of 17 stars, aiming at characterize their spectral variability and establish if it is originated by multiplicity or other causes. In this work we present some preliminary results of this study, i.e.: the discovery that HD 152314 is a multiple system of two long-period binaries, the confirmation that HD 152424 and HD 152723 are binary systems, and the detection of short term radial velocity variations in these stars.