The periodicity of the η Carinae events

  title={The periodicity of the $\eta$ Carinae events},
  author={Augusto Damineli and Michael F. Corcoran and D. John Hillier and Otmar Stahl and Ronaldo Savarino Levenhagen and Nelson Vani Leister and Jose H Groh and Mairan Macedo Teodoro and Juan Facundo Albacete Colombo and F. Gonz{\'a}lez and Julia I Arias and Hugo Levato and Massimiliano Grosso and Nidia I. Morrell and R. C. Gamen and George Wallerstein and V. Avila-Reese Instituto de Astronomia and Geof'isica e Ciencias Atmosf'ericas and Universidade de Sao Paulo and Brazil Department of Physics and Astronomy and University of Pittsburgh and Usa Cresst and X-ray Astrophysics Laboratory and NasaGsfc and Usa Universities Space Research Association and Usa Zah and Landessternwarte and Germany Facultad de Ciencias Astronomicas y Geofisicas de Leoncito and Argentina Departamento de F'isica and Universidad de La Serena and Chile Las Campanas Observatory and Carnegie Observatories and Chile Department of Astronomy and University of Washington and Usa In memoriam},
  journal={Monthly Notices of the Royal Astronomical Society},
Extensive spectral observations of η Carinae over the last cycle, and particularly around the 2003.5 low-excitation event, have been obtained. The variability of both narrow and broad lines, when combined with data taken from two earlier cycles, reveal a common and well-defined period. We have combined the cycle lengths derived from the many lines in the optical spectrum with those from broad-band X-rays, optical and near-infrared observations, and obtained a period length of P pres = 2022.7… Expand

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