The 5.52 Year Cycle of Eta Carinae: BeppoSAX Detection of Variable Hard (> 10 keV) X-Ray Emission

  title={The 5.52 Year Cycle of Eta Carinae: BeppoSAX Detection of Variable Hard (> 10 keV) X-Ray Emission},
  author={S. Rebecchi and Rodolfo Viotti and Paola Grandi and L. Angelo Antonelli and Michael F. Corcoran and Augusto Damineli and Corinne Rossi},
I have discovered spectroscopic variations correlated with the photometric near-infrared (NIR) light curve in η Carinae. The fading of the high-excitation lines is coincident with the peaks in the NIR light curve, strongly resembling an S Doradus type of variability. The cycle, however, is highly stable, and the 5.52 yr period fits well all the shell episodes reported in the last 50 years. This period also recovers the three historical bursts of the last century, in phase with the present low… Expand
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