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تسجيل مستخدم جديدRomanos star in M33 - LBV candidate or LBV?
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R.Kurtev
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We present the light curve of Luminous Blue Variable candidate star GR290 (Romanos star) in M33. The photographic photometry was made in photographic plates taken in B band of the M33 galaxy and cover an eight year period, 1982 - 1990. Twenty five plates, separated in seven groups, have been used. CCD B magnitude of the star is also presented. The analysis of our data together with the Romanos magnitudes (1978) shows normal eruptions with amplitude of more than 1 mag and timescale of about 20 years and smaller oscillations with amplitude 0.5 mag and a period of about 320 days. This is a typical photometrical behavior for LBVs.
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We study the long term, S Dor-type variability and the present hot phase of the LBV star GR290 (Romanos Star) in M33 in order to investigate possible links between the LBV and WNL stages of very massive stars. We use intermediate resolution spectra,
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