Abstract

MARYEVA, O.  and  ABOLMASOV, P. Spectral Variability of Romano's Star. Rev. mex. astron. astrofis [online]. 2010, vol.46, n.2, pp.279-290. ISSN 0185-1101.

We combine archival spectral observations of the LBV star V532 (Romano's star) together with existing photometric data in the B band. Spectroscopic data cover 15 years of observations (from 1992 to 2007). We show that the object in máximum of brightness behaves as an emission line supergiant while in mínimum V532 moves along the sequence of late WN stars. In this sense, the object behaves similarly to the well-known Luminous Blue Variable (LBV) stars AG Car and R127, but is somewhat hotter at the mínima. We identify about 100 spectral lines in the 3700 - 7300 Å wavelength range. As of today, our spectroscopy is the most comprehensive for this object. The velocity of the wind is derived using the He I triplet lines (360 ±30 km s^-1). Physical parameters of the nébula around V532 are estimated.

Keywords : galaxies [individual (M33)]; stars [individual (Romano's star)]; stars [Wolf-Rayet]; supergiants.

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