Multiwavelength study of the intriguing massive star CPD−59 2629 (Tr 16-22)

• Published in: Bulletin de la Société royale des sciences de Liège Vol. 80
• Main Authors: J. A. Combi, J. F. Albacete-Colombo, P. L. Luque Escamilla, G. E. Romero, R. Gamen, P. Benaglia, J. Martí, J. López-Santiago, E. Sánchez-Ayaso, A. J. Muñoz-Arjonilla, J. R. Sánchez-Sutil
• Format: Journal Article
• Language: English
• Published: Université de Liège 01.01.2011
• ISSN: 0037-9565; 1783-5720

We report preliminary results of a multi-wavelength (radio–optical–X-ray) study of the massive star CPD −59 2629 (Tr 16-22) in the Carina Nebula (NGC 3372). This star has historically shown a large X-ray excess (log LX/Lbol < −6 or even larger), which is one order of magnitude larger than expected from single massive O-type stars. A colliding wind scenario is a plausible explanation. On this subject, we searched for non-thermal radio emission and used high-resolution optical spectroscopy to check for multiplicity and investigate the nature of the stars as well as the origin and excess of the X-ray emission. We detected long-term radial-velocity and X-ray variability. Both results suggest that Tr 16-22 is a long-term massive binary system and a variable colliding wind shock scenario.