Optical spectroscopy of X-Mega targets in the Carina nebula : VII. On the multiplicity of Tr 16-112, HD 93343 and HD 93250

We present the results of a spectroscopic monitoring campaign devoted to three O-type stars in the Carina nebula. We derive the full SB2 orbital solution of the binary system Tr 16-112, an exceptional dissymmetrical system consisting of an O5.5-6 V((f+?p)) primary and a B2 V-III secondary. We also r...

ver descrição completa

Detalhes bibliográficos
Autores: Rauw, G., Nazé, Y., Fernández Lajús, Eduardo, Lanotte, A. A., Solivella, Gladys Rebeca, Sana, H., Gosset, E.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2009
País:Argentina
Recursos:Universidad Nacional de La Plata
Repositório:SEDICI (UNLP)
Idioma:inglês
OAI Identifier:oai:sedici.unlp.edu.ar:10915/82736
Acesso em linha:http://sedici.unlp.edu.ar/handle/10915/82736
Access Level:Acceso aberto
Palavra-chave:Ciencias Astronómicas
Binaries: spectroscopic
Stars: early-type
Stars: fundamental parameters
Stars: individual: HD 93250
Stars: individual: HD 93343
Stars: individual: Tr 16-112
Descrição
Resumo:We present the results of a spectroscopic monitoring campaign devoted to three O-type stars in the Carina nebula. We derive the full SB2 orbital solution of the binary system Tr 16-112, an exceptional dissymmetrical system consisting of an O5.5-6 V((f+?p)) primary and a B2 V-III secondary. We also report on low-amplitude brightness variations in Tr 16-112 that are likely due to the ellipsoidal shape of the O5.5-6 primary revolving in an eccentric orbit around the system's centre of mass. We detect for the first time a clear SB2 binary signature in the spectrum of HD 93343 (O8 + O8), although our data are not sufficient to establish an orbital solution. This system also displays low-amplitude photometric modulations. On the other hand, no indication of multiplicity is found in the optical spectra of HD 93250. Finally, we discuss the general properties of multiple massive stars in the Carina OB1 association.