ОРБІТАЛЬНІ СПЕКТРАЛЬНІ ЗМІННОСТІ У СИМБІОТИЧНІЙ ЗОРІ AG ПЕГАСА

The results of the study of orbital spectral variability due to binary nature of the symbiotic star AG Peqasi are presented. We used high-resolution spectra (R = 28,000) taken by 2-m telescope of the Shamakhi Astrophysical Observatory during 2016–2019, and medium-resolution amateurs’ spectra (R = 9,000–11,000) taken from the Astronomical Ring for Access to Spectroscopy (ARAS) database obtained during 2020–2024. The system’s orbital period is approximately 815 days, and its spectral changes are correlated with this period. In this paper we present the radial velocity curve of the cold component (M3III), as well as the emission lines Hα, Hβ, and the HeII lines λ4686 Å and λ5412 Å formed around the hot component of the AG Peg system, constructed according to our measurements. We determined the mass function of the cool component, f₁ ≈ 0.023 M⊙.