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arXiv · 1308.4505

Spectropolarimetric observations of cool DQ white dwarfs

Tommi Vornanen·Svetlana Berdyugina·Andrei Berdyugin
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Abstract

Following our recent discovery of a new magnetic DQ white dwarf (WD) with CH molecular features, we report the results for the rest of the DQ WDs from our survey. We use high signal-to-noise spectropolarimetric data to search for magnetic fields in a sample of 11 objects. One object in our sample, WD1235+422, shows the signs of continuum circular polarization that is similar to some peculiar DQs with unidentified molecular absorption bands, but the low S/N and spectral resolution of these data make more observations necessary to reveal the true nature of this object.

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Tommi Vornanen, Svetlana Berdyugina, Andrei Berdyugin. 2013-08-21. Spectropolarimetric observations of cool DQ white dwarfs. https://doi.org/10.1051/0004-6361%2F201220619

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