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arXiv · 1305.2290

Modified methods of stellar magnetic field measurements

A. F. Kholtygin
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Abstract

The standard methods of the magnetic field measurement, based on an analysis of the relation between the Stokes $V$-parameter and the first derivative of the total line profile intensity, were modified by applying a linear integral operator $\hat{L}$ to the both sides of this relation. As the operator $\hat{L}$, the operator of the wavelet transform with DOG-wavelets is used. The key advantage of the proposed method is an effective suppression of the noise contribution to the line profile and the Stokes parameter $V$. The efficiency of the method has been studied using the model line profiles with various noise contributions. To test the proposed method, the spectropolarimetric observations of the A0-type star $α^2\,$ CVn, young O-type star $θ^1$ Ori C and A0 supergiant HD 92207 were used. The longitudinal magnetic field strengths for these stars calculated by our method appeared to be in a good agreement with those determined by other methods.

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A. F. Kholtygin. 2013-05-10. Modified methods of stellar magnetic field measurements. https://doi.org/10.1002/asna.201212123

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