The null result of a search for pulsational variations of the surface magnetic field in the roAp star γ Equulei
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چکیده
We describe an analysis of the time-resolved measurements of the surface magnetic field in the roAp star γ Equ. We have obtained a high-resolution and high S/N spectroscopic timeseries, and the magnetic field was determined using Zeeman resolved profiles of the Fe II 6149.25 Å and Fe I 6173.34 Å lines. Contrary to recent reports we do not find any evidence of magnetic variability with pulsation phase, and derive an upper limit of 5–10 G for pulsational modulation of the surface magnetic field in γ Equ.
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تاریخ انتشار 2004