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arXiv · 1104.1829

N II 5668-5712, a New Class of Spectral Features in Eta Carinae

Andrea Mehner·Kris Davidson·Gary J. Ferland
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Abstract

We report on the N II 5668-5712 emission and absorption lines in the spectrum of Eta Carinae. Spectral lines of the stellar wind regions can be classified into four physically distinct categories: 1) low-excitation emission such as H I and Fe II, 2) higher excitation He I features, 3) the N II lines discussed in this paper, and 4) He II emission. These categories have different combinations of radial velocity behavior, excitation processes, and dependences on the secondary star. The N II lines are the only known features that originate in "normal" undisturbed zones of the primary wind but depend primarily on the location of the hot secondary star. N II probably excludes some proposed models, such as those where He I lines originate in the secondary star's wind or in an accretion disk.

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Andrea Mehner, Kris Davidson, Gary J. Ferland. 2011-04-11. N II 5668-5712, a New Class of Spectral Features in Eta Carinae. https://doi.org/10.1088/0004-637x/737/2/70

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