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arXiv · 2410.05469

JWST/MIRI detection of [Ne V], [Ne VI], and [O IV] wind emission in the O9V star 10 Lacertae

David R. Law·Calum Hawcroft·Linda J. Smith·Alexander W. Fullerton·Christopher J. Evans·Karl D. Gordon·Nimisha Kumari·Claus Leitherer
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Abstract

We report the detection of broad, flat-topped emission in the fine-structure lines of [Ne V], [Ne VI], and [O IV] in mid-infrared spectra of the O9 V star 10 Lacertae obtained with JWST/MIRI. Optically thin emission in these high ions traces a hot, low-density component of the wind. The observed line fluxes imply a mass-loss rate of > 3 x 10^8 Msun/yr, which is an order of magnitude larger than previous estimates based on UV and optical diagnostics. The presence of this hot component reconciles measured values of the mass-loss rate with theoretical predictions, and appears to solve the "weak wind" problem for the particular case of 10 Lac.

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David R. Law, Calum Hawcroft, Linda J. Smith, Alexander W. Fullerton, Christopher J. Evans, Karl D. Gordon, Nimisha Kumari, Claus Leitherer. 2024-10-07. JWST/MIRI detection of [Ne V], [Ne VI], and [O IV] wind emission in the O9V star 10 Lacertae. https://arxiv.org/abs/2410.05469

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