Small-scale variability in the spectrum of Vega
| 1Pokhvala, SM, 1Zhilyaev, BE 1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine |
| Kinemat. fiz. nebesnyh tel (Online) 2025, 41(3):32-43 |
| https://doi.org/10.15407/kfnt2025.03.032 |
| Язык: Ukrainian |
Аннотация: We reported the results of observations of small-scale variability in the hydrogen Balmer lines in Vega. Spectral observations were carried out with low-resolution spectrograph (R ~ 600) installed in the Main Astronomical Observatory, Ukraine. Spectra were obtained with a time resolution in the second range. It has been found that Vega shows variations in the hydrogen lines Hβ, Hγ, Hδ. This can be interpreted that their variations are non-radial pulsations. The characteristic time of the observed variations ranges from 300 to 1200 s. The horizontal scale for oscillating elements is about 800 Mm, which is comparable to the solar radius. The radial velocity of the variations is about 36 km/s. |
| Ключевые слова: instrumentation: detectors, methods: observational, processing techniques: spectrometric, stars: imaging introduction, techniques: image |
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