Hα and Hβ profile variations in spectra of the 55 Cyg star

1Maharramov, YM
1Nasir al-Din al-Tusi Shamakhi Astrophysical Observatory, Pirqulu, Azerbaijan
Kinemat. fiz. nebesnyh tel (Online) 2013, 29(2):40-49
Start Page: Physics of Stars and Interstellar Medium
Language: Russian
Abstract: 

Profile variations for the Hα and Hβ lines in spectra of the 55 Cyg star are investigated using some observations in the Cassegrain focus of the 2-m telescope of the ShAO (Azerbaijan, NAS) which were obtained in 2010 with a spectral resolution of about 15000. It is found that emission and absorption components of the Hα profile are absent for some observational days and the inverse P Cyg profile is present for one observation. We suppose that the obtained observational facts of the 55 Cyg atmosphere nonstationarity can be partially connected with the stellar wind nonsphericality.

Keywords: non-stationary atmosphere, star 55 Cyg
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