Investigation of atmosphere nonstationarity in the supergiant HD 225094. Profile variations of the Hα and Hβ lines in the spectra of the star HD 225094

1Maharramov, YM, 1Khalilov, VM
1Nasir al-Din al-Tusi Shamakhi Astrophysical Observatory, Pirqulu, Azerbaijan
Kinemat. fiz. nebesnyh tel (Online) 2015, 31(3):63-72
Start Page: Physics of Stars and Interstellar Medium
Language: Russian
Abstract: 

Some information on the star HD225094 and on unusual features of spectra obtained at the ShAO in 2013 is presented. It is revealed that profiles of the Hα line of the P Cyg type has some structure changing in a short time. Besides, we revealed the unique observational fact of the Hα profile disappearance in the spectra of the star HD 225094. Our investigation of the Hα and Hβ lines in the spectra of the star shows that values of the radial velocity and spectral parameters in these lines change with time. We suppose that the obtained observational facts of the HD 225094 atmosphere nonstationarity can be partially connected with the stellar wind nonsphericality.

Keywords: atmosphere, HD 225094
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