Eclipse and Collapse of the Colliding Wind X-ray Emission from Eta Carinae
Abstract
X-ray emission from the massive colliding wind binary system, Eta Carinae, plunges sharply around periastron passage, which corresponds to a minimum in X-ray emission. An X-ray observing campaign of Eta Carinae around periastron passage in 2003 presented two different scenarios for the mechanism --- (i) eclipse of X-ray emitting plasma by the thick primary wind and (ii) decay of the colliding wind activity by a change in the wind collision structure near periastron.
We launched another focused observing campaign on Eta Carinae around the 2009 periastron passage with RXTE, Chandra, XMM-Newton, Suzaku and Swift. X-ray emission from Eta Carinae declined as in the previous minimum, though it recovered a month earlier than expected. Changes in X-ray absorption and spectral normalization suggest that the early part of the X-ray minimum would be driven by an X-ray eclipse, while the latter part is caused by an activity decay. We present the results, mainly focusing on the Suzaku observation, and discuss the stellar and binary properties of Eta Carinae.- Publication:
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AAS/High Energy Astrophysics Division #12
- Pub Date:
- September 2011
- Bibcode:
- 2011HEAD...12.2703H