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The null result of a search for pulsational variations of the surface magnetic field in the roAp star gamma Equulei

O. Kochukhov·T. Ryabchikova·J. D. Landstreet·W. W. Weiss
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Abstract

We describe an analysis of the time-resolved measurements of the surface magnetic field in the roAp star gamma Equ. We have obtained a high-resolution and high S/N spectroscopic time-series, and the magnetic field was determined using Zeeman resolved profiles of the Fe II 6149.25 A and Fe I 6173.34 A 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 gamma Equ.

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O. Kochukhov, T. Ryabchikova, J. D. Landstreet, W. W. Weiss. 2004-04-27. The null result of a search for pulsational variations of the surface magnetic field in the roAp star gamma Equulei. https://doi.org/10.1111/j.1365-2966.2004.07946.x

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