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arXiv · astro-ph/0102006

Identification of the 4486,4504A emission lines in O-type spectra

K. Werner·T. Rauch
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Abstract

Inspired by an appeal to the community from Walborn (these proceedings) we decided to solve the long-standing problem concerning the nature of the 4486,4504A emission lines, which are frequently observed in O-type spectra and which are particularly prominent in supergiants. We claim that these lines emerge from sulfur, namely by de-excitation of a highly excited S IV doublet state. We prove this by an exploratory NLTE calculation with a detailed model atom.

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K. Werner, T. Rauch. 2001-02-01. Identification of the 4486,4504A emission lines in O-type spectra. https://arxiv.org/abs/astro-ph/0102006

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