Simultaneous photoelectric and polarimetric BVR measurements of RY Tau were made from December, 1987 to March, 1993, after the star's extraordinary brightness increase on October, 1983.The presence of a correlation between polarization and photometric variability was found near the new light maximum of the star. But when the star becomes fainter than some brightness level, the correlation disappears and peculiarities of the P parameter behaviour resemble those before the RY Tau "flash". The position angle varied from 0' to 40' without any correlations with photometric variability or with polarization value. The interpretation of the observed phenomena was made by comparison with a "flash" of another T Tauri star, DR Tau "flash". We assumed the presence of two young stars in the direction of RY Tau. One of them is the well-known object. It is a probable close binary system. Another one is the YY Ori type companion which flashed.
KEY WORDS etryPre-main-sequence stellar evolution, T Tau type stars, polarimetry and photom-
Spectroscopic data taken with a moderate resolution spectrograph in the region of the Hα and Hβ lines are presented for the Herbig B8e star MWC 419. The spectroscopic observations were accompanied by broad band BVR photometric measurements. The observations reveal a variability in the line profiles that is typical of Herbig Ae/Be stars with signs of a strong stellar wind. The greatest changes are observed in the region of the absorption components of the line profiles, which convert the profile from a type P CygII to P CygIII, as well as in the intensities of the central emission components. A model technique is used for quantitative interpretation of this variability and it shows that the P Cyg profile conversion of the absorption component can be explained in terms of a stellar wind model in which its distribution over latitude varies on a time scale of a few days.
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