Abstract
We discuss the history of X-ray observations of the η Car system, concentrating on the periodic variability discovered in the 1990s. We discuss the interpretation of these variations, concentrating on a model of the system as a “colliding-wind” binary. This interpretation allows the physical and orbital parameters of η Car and its companion star to be constrained.
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Acknowledgements
The authors would like to acknowledge many fruitful discussions with a large number of colleagues, among them Kris Davidson, Ted Gull, Roberta Humphreys, Augusto Damineli, Jean Swank, Stephen White, Julian Pittard, David Henley, Tony Moffat, Stan Owocki, John Hillier, Virpi Niemela, Nolan Walborn, and many others too numerous to fully mention. This work was supported in part by Chandra grant GO3-4008A and NASA grant NAS5-32490. This research made use of software and data available from the High Energy Astrophysics Science Archive Research Center, and NASA’s Astrophysics Data System.
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Corcoran, M.F., Ishibashi, K. (2012). X-ray Variability and the Secondary Star. In: Davidson, K., Humphreys, R. (eds) Eta Carinae and the Supernova Impostors. Astrophysics and Space Science Library, vol 384. Springer, Boston, MA. https://doi.org/10.1007/978-1-4614-2275-4_9
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