author={Francisco Najarro and Donald F. Figer and D. John Hillier and Thomas R. Geballe and Rolf Peter Kudritzki},
  journal={The Astrophysical Journal},
  pages={1816 - 1827}
We present a measurement of metallicity in the Galactic center Quintuplet cluster made using quantitative spectral analysis of two luminous blue variables (LBVs). The analysis employs line-blanketed non-LTE wind/atmosphere models fit to high-resolution near-infrared spectra containing lines of H, He i, Si ii, Mg ii, and Fe ii. We are able to break the H/He ratio versus mass-loss rate degeneracy found in other LBVs and to obtain robust estimates of the He content of both objects. Our results… 


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