Abstract
New measurements of the longitudinal magnetic field of the Ap star γ Equ obtained with the MSS spectrograph of the 6-m telescope of the SAO RAS in 2002–2018 are present. Analyzing our results together with all the available literature data sources of 〈Bz〉 (441 measurements) we found the rotation period P = 89.1 ± 4.2 years (32 521 days). Fitting all the measurements with double sine-wave function resulted in two periods equal to 95.5 and 17.4 years (with the errors of 3.5 and 2 years correspondingly). According to our new estimate, the transition to positive values of 〈Bz〉, probably, will occur later than previously assumed, literally in 2031.
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Original Russian Text © I.S. Savanov, I.I. Romanyuk, E.S. Dmitrienko, 2018, published in Astrofizicheskii Byulleten’, 2018, Vol. 73, No. 4, pp. 490–493.
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Savanov, I.S., Romanyuk, I.I. & Dmitrienko, E.S. Long-Term Variability in the Magnetic Field of the Ap Star γ Equ. Astrophys. Bull. 73, 463–465 (2018). https://doi.org/10.1134/S1990341318040089
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DOI: https://doi.org/10.1134/S1990341318040089