Investigation of spectral line Hα and doublet of sodium Na D in a spectrum of the star post-AGB HD 161796
| 1Hasanova, AR, 1Khalilov, AM, 1Maharramov, YM 1Nasir al-Din al-Tusi Shamakhi Astrophysical Observatory, Pirqulu, Azerbaijan |
| Kinemat. fiz. nebesnyh tel (Online) 2014, 30(6):42-53 |
| Start Page: Physics of Stars and Interstellar Medium |
| Language: Russian |
Abstract: Some variability of a profile of the line Hα and doublet of sodium Na D in a spectrum of the star HD161796 are investigated on the basis of the spectrograms obtained at the two-metre telescope of the Shamakhy Astrophysical Observatory (ShAO). It turns out that values of radial velocities, equivalent width of the profile of the line Hα, and equivalent width of a doublet of sodium vary synchronously with changes of the amplitude of light curve V which occur with the known period P = 62 days. The changes of radial velocity of the D2 line of the sodium doublet (Na I, λ 588.9953 nm) occur in an аntiphase to changes of the light curve V, radial velocity of line Hα, and equivalent widths of the Hα and D2 lines. |
| Keywords: HD 161796, Shamakhy Astrophysical Observatory |
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