ON THE NATURE OF THE PROTOTYPE LUMINOUS BLUE VARIABLE AG CARINAE. I. FUNDAMENTAL PARAMETERS DURING VISUAL MINIMUM PHASES AND CHANGES IN THE BOLOMETRIC LUMINOSITY DURING THE S-Dor CYCLE

@article{Groh2009ONTN,
  title={ON THE NATURE OF THE PROTOTYPE LUMINOUS BLUE VARIABLE AG CARINAE. I. FUNDAMENTAL PARAMETERS DURING VISUAL MINIMUM PHASES AND CHANGES IN THE BOLOMETRIC LUMINOSITY DURING THE S-Dor CYCLE},
  author={Jose H Groh and D. John Hillier and Augusto Damineli and P. A. Whitelock and Freddy Marang and C. Rossi},
  journal={The Astrophysical Journal},
  year={2009},
  volume={698},
  pages={1698 - 1720}
}
We present a detailed spectroscopic analysis of the luminous blue variable (LBV) AG Carinae (AG Car) during the last two visual minimum phases of its S-Dor cycle (1985–1990 and 2000–2003). The analysis reveals an overabundance of He, N, and Na, and a depletion of H, C, and O, on the surface of the AG Car, indicating the presence of a CNO-processed material. Furthermore, the ratio N/O is higher on the stellar surface than in the nebula. We found that the minimum phases of AG Car are not equal to… 
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