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arXiv · 2009.12380

Rapid Variability in the Wind from the White Dwarf Merger Candidate J005311

P. Garnavich·C. Littlefield·R. Pogge·C. Wood
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Abstract

We analyze time-series spectroscopy of the white dwarf merger candidate J005311 and confirm the unique nature of its optical spectrum. We detect an additional broad emission feature peaking at 343nm that was predicted in the Gvaramadze et al. (2019; arXiv:1904.00012) models. Comparing ten spectra taken with the Large Binocular Telescope (LBT), we find significant variability in the profile of the strong OVI 381.1/383.4nm emission feature. This appears to be caused by rapidly shifting subpeaks generated by clumpiness in the stellar wind of J005311. This line variability is similar to what is seen in many Wolf-Rayet stars. However, in J005311, the rate of motion of the subpeaks appears exceedingly high as they can reach 16000 km/s in less than two hours.

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P. Garnavich, C. Littlefield, R. Pogge, C. Wood. 2020-09-25. Rapid Variability in the Wind from the White Dwarf Merger Candidate J005311. https://arxiv.org/abs/2009.12380

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