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A Spectroscopic Analysis of Blue Stragglers, Horizontal Branch and Turn-Off Stars in Four Globular Clusters

Orsola De Marco·Michael M. Shara·D. Zurek·John A. Ouellette·Thierry Lanz·Rex A. Saffer·Jeremy F. Sepinsky
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Abstract

We present a spectroscopic analysis of HST/STIS and FOS low- and intermediate-resolution spectroscopy of 55 stars (turn-off stars, horizontal branch stars and blue stragglers) in four globular clusters (47 Tucanae, M3, NGC6752, and NGC6397). Stars were analyzed with non-Local Thermodynamic Equilibrium model atmospheres, and values for their effective temperatures and gravities and some rotation rates were obtained. Using photometric fluxes, we also obtained radii, luminosities and spectroscopic masses.

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Orsola De Marco, Michael M. Shara, D. Zurek, John A. Ouellette, Thierry Lanz, Rex A. Saffer, Jeremy F. Sepinsky. 2005-11-16. A Spectroscopic Analysis of Blue Stragglers, Horizontal Branch and Turn-Off Stars in Four Globular Clusters. https://doi.org/10.1086/444372

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