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arXiv · 1109.0445

Spectral Study of the WNL Star FSZ35 in the M33 Galaxy

Olga Maryeva·Pavel Abolmasov
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Abstract

We study and analyse low-resolution spectra of the unordinary late WN star FSZ35 in M33. We classify the object as a hydrogen-rich WN8 star. Using the radiative transfer code CMFGEN, we determine the physical parameters of this object and compare them to the parameters of other WN8 stars including the LBV star Romano's star during the minimum of brightness. Unlike Romano's star, the object is fairly stable both spectrally and photometrically, that may be attributed to its more advanced evolutionary stage or lower luminosity. FSZ35 is shown to possess a compact nebula producing faint but detectable [OIII]emission. Location of this object at a large distance (about 100 pc) from the nearest association suggests the object may be one more example of a massive runaway star.

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Olga Maryeva, Pavel Abolmasov. 2011-09-02. Spectral Study of the WNL Star FSZ35 in the M33 Galaxy. https://arxiv.org/abs/1109.0445

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