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

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.

4 figures, 1 table

References in corpus (9)

• Chemical evolution of galaxies. I. A composition-dependent SPH model for chemical evolution and cooling
• A multispectral view of the periodic events in eta Carinae
• The Early Spectra of Eta Carinae 1892 to 1941 and the Onset of Its High Excitation Emission Spectrum
• A Sea Change in Eta Carinae
• He II 4686 in eta Carinae: collapse of the wind-wind collision region during periastron passage
• Accretion onto the Companion of Eta Carinae During the Spectroscopic Event: III. the He II 4686 Line
• The Source of the Helium Visible Lines in Eta Carinae
• The Orientation of the Eta Carinae Binary System
• Explaining the Early Exit of Eta Carinae from its 2009 X-Ray Minimum with the Accretion Model

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• Simulating the Response of the Secondary Star of Eta Carinae to Mass Accretion at Periastron Passage
• The Optical Wind Line Variability of $\eta$ Carinae During the 2009.0 Event
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