HD 152248: Evidence for a colliding wind interaction

Citation
H. Sana et al., HD 152248: Evidence for a colliding wind interaction, ASTRON ASTR, 370(1), 2001, pp. 121-135
Citations number
44
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
0004-6361 → ACNP
Volume
370
Issue
1
Year of publication
2001
Pages
121 - 135
Database
ISI
SICI code
0004-6361(200104)370:1<121:H1EFAC>2.0.ZU;2-I
Abstract
We present the results of a four year spectroscopic campaign on the early-t ype binary system HD 152248. Our analysis yields a new classification as 07 .5III(f) + 07III(f), in contradiction with previous classifications of the components as supergiants. We derive improved orbital elements and the corr esponding masses (M-1 = 29.61M(circle dot) and M-2= 29.9 M-circle dot) are somewhat larger than previously reported in the literature, although they a re still significantly lower than the ones expected from evolutionary track s. Both components of the system are close to filling their Roche lobe at p eriastron passage. We also investigate the equivalent width Variations of t he lines of the two components and we discuss their relation to the Struve- Sahade effect. Finally, we show that the line profile variability of the He II lambda 4686 and H alpha lines is consistent with a strong wind interact ion between the two stars, quite as predicted by current colliding wind mod els.