Probing the Faintest Stars in a Globular Star Cluster

  title={Probing the Faintest Stars in a Globular Star Cluster},
  author={Harvey B. Richer and Jay Anderson and James P. Brewer and Saul D. Davis and Gregory G. Fahlman and Brad Hansen and Jarrod Hurley and Jason S. Kalirai and Ivan R. King and David Brian Reitzel and Robert Michael Rich and Michael M. Shara and Peter B. Stetson},
  pages={936 - 940}
NGC 6397 is the second closest globular star cluster to the Sun. Using 5 days of time on the Hubble Space Telescope, we have constructed an ultradeep color-magnitude diagram for this cluster. We see a clear truncation in each of its two major stellar sequences. Faint red main-sequence stars run out well above our observational limit and near to the theoretical prediction for the lowest mass stars capable of stable hydrogen burning in their cores. We also see a truncation in the number counts of… 

M dwarfs at large heliocentric distances

We present an analysis of the faint M star population seen as foreground contaminants in deep extragalactic surveys. We use space-based data to separate such stars from high-redshift galaxies in a

White dwarfs as astrophysical probes

  • J. Kalirai
  • Physics
    Proceedings of the International Astronomical Union
  • 2008
Abstract Much of our knowledge regarding the ages of stars derives from our understanding of the Hertzsprung-Russell Diagram. The diagram is typically dominated by hydrogen burning main-sequence

A comparative analysis of the observed white dwarf cooling sequence from globular clusters

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Recent years have seen a substantial improvement both in photometry of low-luminosity stars in globular clusters and in modeling the stellar atmospheres of late-type dwarfs. We build on these

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