Absolute ages of globular clusters and the age of the universe

  title={Absolute ages of globular clusters and the age of the universe},
  author={Brian Chaboyer},
  journal={The Astrophysical Journal},
  • B. Chaboyer
  • Published 6 December 1994
  • Physics
  • The Astrophysical Journal
The main sequence turnoff luminosity is the best stellar `clock' which can be used to determine the absolute ages of globular clusters. This is due to the fact that it is generally assumed that the luminosity and lifetimes of main sequence globular cluster stars are independent of the properties of stellar convection and atmospheres, two areas of stellar evolution which are poorly understood. Several possible sources of error in this stellar clock are discussed, and isochrones are constructed… 

Tables from this paper

A Lower Limit on the Age of the Universe
A detailed numerical study was designed and conducted to estimate the absolute age and the uncertainty in age (with confidence limits) of the oldest globular clusters in our galaxy, and hence to put
The Age of Globular Clusters in Light of Hipparcos: Resolving the Age Problem?
We review five independent techniques that are used to set the distance scale to globular clusters, including subdwarf main-sequence fitting utilizing the recent Hipparcos parallax catalog. These
The Age of the Globular Cluster M68
Relying on the accurate color-magnitude diagram (CMD) presented by Walker in 1994, we use the fitting of moderately hot horizontal-branch models to the observed CMD to derive suitable information
The Age of the Oldest Globular Clusters
The age of three of the oldest clusters—M15, M68, M92—has been redetermined. We use the latest equation of state (EOS) and opacity data available for calculating both isochrones and zero-age
▪ Abstract A careful assessment of current uncertainties in stellar physics (opacities, nuclear reaction rates, equation of state effects, diffusion, rotation, and mass loss), in the chemistry of
A New Self-consistency Check on the Ages of Globular Clusters
We present a new method to compute stellar ages in globular clusters (GCs) that is 10 times more precise than the traditional isochrone-fitting procedure. The method relies on accurate stellar
Stellar evolution in globular clusters
1. Summaries are given of the major stages of evolution for stars in globular clusters, including the nucleosynthesis networks, and their sensitivities to chemical abundances. Difficulties in
A lower limit of 9.5 Gyr on the age of the Galactic disk from the oldest white dwarf stars
WHITE dwarf stars represent the final evolutionary state for most main-sequence stars. They cool slowly enough that even the oldest white dwarfs are still observable in sufficiently deep surveys and
White Dwarf Cosmochronometry. I. Monte Carlo Simulations of Proper-Motion- and Magnitude-limited Samples using Schmidt's 1/Vmax Estimator
Observationally, white dwarf stars are a remarkably homogeneous class with a minimum observed Teff ~ 4000 K. Theoretically, the physics that determines their cooling timescales is relatively more
The age of the Milky Way halo stars from the Sloan Digital Sky Survey
We determined the age of the stellar content of the Galactic halo by considering main-sequence turn-off stars. From the large number of halo stars provided by Sloan Digital Sky Survey, we could


Observational Tests of Cosmological Inflation
I. Inflation Theory.- Fundamental Arguments for Inflation.- Predictions of Inflation.- Classicality of Density Perturbations in the Early Universe.- The Influence of Non-Linear Density Fluctuations
Observational Tests of Cosmological InflationDordrecht: Kluwer)
  • Observational Tests of Cosmological InflationDordrecht: Kluwer)
  • 1991
Inside the Stars, IAU Col
  • Inside the Stars, IAU Col
  • 1993
  • ApJS
  • 1992
  • ApJS
  • 1991
Stellar Atmospheres: Beyond Classical ModelsDordrecht: Kluwer)
  • Stellar Atmospheres: Beyond Classical ModelsDordrecht: Kluwer)
  • 1991
Astrophysical ages and dating methods
Cosmic Abundances of Matter
  • Cosmic Abundances of Matter
  • 1989
Neutrino Astrophysics (Cambridge
  • 1989