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Kilo-gauss Magnetic Fields in three DA White Dwarfs

R. Aznar Cuadrado·S. Jordan·R. Napiwotzki·H. M. Schmid·S. K. Solanki·G. Mathys
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Abstract

We have detected longitudinal magnetic fields between 2 and 4kG in three normal DA white dwarfs (WD0446-790, WD1105-048, WD2359$-$434) out of a sample of 12 by using optical spectropolarimetry done with the VLT Antu 8 m telescope equipped with FORS1. With the exception of 40 Eri B (4kG) these are the first positive detections of magnetic fields in white dwarfs below 30kG. A detection rate of 25% (3/12) may indicate now for the firsttime that a substantial fraction of white dwarfs have a weak magnetic field.This result, if confirmed by future observations, would form a cornerston for our understanding of the evolution of stellar magnetic fields.

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R. Aznar Cuadrado, S. Jordan, R. Napiwotzki, H. M. Schmid, S. K. Solanki, G. Mathys. 2005-01-11. Kilo-gauss Magnetic Fields in three DA White Dwarfs. https://arxiv.org/abs/astro-ph/0501191

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