EDP Sciences
Free access
Volume 409, Number 2, October II 2003
Page(s) 665 - 675
Section Stellar atmospheres
DOI http://dx.doi.org/10.1051/0004-6361:20031159

A&A 409, 665-675 (2003)
DOI: 10.1051/0004-6361:20031159

Using spectroscopic analysis of unclassified supergiants to investigate massive stars in transition

II. The superluminous HD 327083
M. A. D. Machado and F. X. de Araújo

Observatório Nacional-MCT, Rua José Cristino, 77, CEP 20921-400, São Cristóvão, Rio de Janeiro-RJ, Brazil
(Received 16 January 2003 / Accepted 7 July 2003)

New optical high-resolution ( $R\approx50\,000$) spectra of the star HD 327083 are reported in this paper. The Balmer and Fe II lines show P Cygni profiles while He I lines are all in pure absorption, resembling the spectra of the Luminous Blue Variable HR Carinae. However, the blue absorption components of the Balmer lines are more pronounced and the Fe II lines are less numerous and less intense in HD 327083. A spectroscopic analysis of the Balmer lines (H $\alpha$, H $\beta$, H $\gamma$ and H $\delta$) with a non-LTE wind model has been performed. The derived stellar parameters for HD 327083 are: $\log(L_\star/L_\odot) = 6.0$, $T_\star$ = 11 500 K, $\dot M =
8.0 \times 10^{-5}~M_\odot$ /yr and He/H = 0.2 (by number). From these results we concluded that HD 327083 is a superluminous object in an evolved phase of an evolutive track of $M_{\rm ZAMS} \sim $ 60 $M_\odot$. It is likely to be about to enter in a Luminous Blue Variable phase.

Key words: stars: emission-line, Be -- stars: variables: general -- stars: individual: HD 327083

Offprint request: M. A. D. Machado, dora@on.br

SIMBAD Objects

© ESO 2003