The first orbital solution for the massive colliding-wind binary HD 93162 (≡WR 25)

Context. Since the discovery, with the EINSTEIN satellite, of strong X-ray emission associated with HD 93162 (≡WR 25), this object has been predicted to be a colliding-wind binary system. However, radial-velocity variations that would prove the suspected binary nature have yet to be found. Aims. We...

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Detalles Bibliográficos
Autores: Gamen, Roberto Claudio, Gosset, E., Morrell, Nidia Irene, Niemelä, Virpi Sinikka, Sana, H., Nazé, Y., Rauw, G., Barbá, Rodolfo Héctor, Solivella, Gladys Rebeca
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2006
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/83059
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/83059
Access Level:acceso abierto
Palabra clave:Ciencias Astronómicas
Stars: binaries: spectroscopic
Stars: individual: HD 93162
Stars: Wolf-Rayet
Descripción
Sumario:Context. Since the discovery, with the EINSTEIN satellite, of strong X-ray emission associated with HD 93162 (≡WR 25), this object has been predicted to be a colliding-wind binary system. However, radial-velocity variations that would prove the suspected binary nature have yet to be found. Aims. We spectroscopically monitored this object to investigate its possible variability to address this discordance. Methods. We compiled the largest available radial-velocity data set for this star to look for variations that might be due to binary motion. We derived radial velocities from spectroscopic data acquired mainly between 1994 and 2006, and searched these radial velocities for periodicities using different numerical methods. Results. For the first time, periodic radial-velocity variations are detected. Our analysis definitively shows that the Wolf-Rayet star WR 25 is an eccentric binary system with a probable period of about 208 days.