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Zeeman tomography of magnetic white dwarfs: General method and application to EF Eridani

F. Euchner·K. Beuermann·K. Reinsch·S. Jordan·F. V. Hessman·B. T. Gaensicke
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Abstract

We have developed a new method to derive the magnetic field distribution on the surfaces of rotating magnetic white dwarfs from phase-resolved flux and circular polarization spectra. An optimization code based on an evolutionary strategy is used to fit synthetic Zeeman spectra for a variety of model geometries described in the framework of a truncated multipole expansion. We demonstrate that the code allows the reconstruction of relatively complex fields using noise-added synthetic input spectra. As a first application, we analyze flux and circular polarization spectra of the polar EF Eri in a low state of accretion taken with FORS1 at the ESO VLT.

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F. Euchner, K. Beuermann, K. Reinsch, S. Jordan, F. V. Hessman, B. T. Gaensicke. 2003-03-14. Zeeman tomography of magnetic white dwarfs: General method and application to EF Eridani. https://arxiv.org/abs/astro-ph/0303336

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