Based on observations obtained with ESO telescopes at the La Silla Paranal Observatory under programme ID 088.D-044 and at the Gemini Observatory which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (USA), the Science and Technology Facilities Council (UK), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), under programme ID GS-2010B-Q-31.
The sudden appearance of CO emission in LHA 115-S 65★
Article first published online: 20 AUG 2012
© 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS
Monthly Notices of the Royal Astronomical Society: Letters
Volume 426, Issue 1, pages L56–L60, October 2012
How to Cite
Oksala, M. E., Kraus, M., Arias, M. L., Borges Fernandes, M., Cidale, L., Muratore, M. F. and Curé, M. (2012), The sudden appearance of CO emission in LHA 115-S 65. Monthly Notices of the Royal Astronomical Society: Letters, 426: L56–L60. doi: 10.1111/j.1745-3933.2012.01323.x
- Issue published online: 1 OCT 2012
- Article first published online: 20 AUG 2012
- Accepted 2012 July 25. Received 2012 July 25; in original form 2012 June 12
- circumstellar matter;
- stars: emission-line, Be;
- stars: individual: LHA 115-S 65;
- stars: winds, outflows
Molecular emission has been detected in several Magellanic Cloud B[e] supergiants. In this Letter, we report on the detection of CO band head emission in the B[e] supergiant LHA 115-S 65, and present a K-band near-infrared spectrum obtained with the Spectrograph for INtegral Field Observation in the Near-Infrared (SINFONI; R= 4500) on the ESO VLT UT4 telescope. The observed molecular band head emission in S65 is quite surprising in the light of a previous non-detection by McGregor, Hyland & McGinn, as well as a high-resolution (R= 50 000) Gemini/Phoenix spectrum of this star taken nine months earlier showing no emission. Based on analysis of the optical spectrum by Kraus, Borges Fernandes & de Araújo, we suspect that the sudden appearance of molecular emission could be due to density build-up in an outflowing viscous disc, as seen for Be stars. This new discovery, combined with variability in two other similar evolved massive stars, indicates an evolutionary link between B[e] supergiants and luminous blue variables.