Violet Spectra of Carbon Stars Associated with Silicate Features
We have observed the violet spectra of three carbon stars, BM Gem, V778 Cyg, and EU And, that are associated with silicate dust emission features as well as that of a proto-typical J-type carbon star, Y CVn, with the high dispersion spectrograph (HDS) on SUBARU telescope. The spectrum of BM Gem has revealed the presence of Balmer lines up to H23, all of which are found to have P-Cyg type line profile, as well as the Paschen and Balmer continuum emission. The blue-shifted absorption gives the gas outflow velocity of about 400 km s-1, that is very unusual for a cool carbon star. Our results strongly suggest the existence of a low luminosity companion surrounded by an accretion disk in BM Gem system, which have long been postulated but has never been confirmed. We have not detected either continuum or line emission in the violet region shortward of 4000Å in the other two silicate carbon stars
KeywordsStellar evolution mass-loss thermal pulses carbon stars silicates Balmer lines BM Gem
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- Nakada, Y., Izumiura, H., Onaka, T., Hashimoto, O., Ukita, N., Deguchi, S. & Tanabe, T. 1987, ApJ, 323, L77Google Scholar
- Noguchi, K., Aoki, W., Kawanomot, S., Ando, H., Honda, S., Izumiura, H., Kambe, E., Okita, K., Sadakane, K., Sato, B., Takada-Hidai, M., Tanaka, W., & Watanabe, E. 2002, PASJ, submittedGoogle Scholar