High-Excitation Emission Lines Near Eta Carinae, and Its Likely Companion Star

  title={High-Excitation Emission Lines Near Eta Carinae, and Its Likely Companion Star},
  author={A. Mehner and Kris Davidson and G. J. Ferland and Roberta M. Humphreys},
  journal={The Astrophysical Journal},
In order to study the distribution of gas and ionizing radiation around η Car and their implications for its likely companion star, we have examined high-excitation emission lines of [Ne III], [Fe III], etc., in spectra obtained with the Hubble Space Telescope/Space Telescope Imaging Spectrograph instrument during 1998-2004. Our principal results, some of them unexpected, are as follows. (1) The high-excitation fluxes varied systematically and non-trivially throughout η Car's 5.5 year… Expand
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