The Absolute Age of M92

Abstract

The \textit{absolute age} of a simple stellar population is of fundamental interest for a wide range of applications but is difficult to measure in practice, as it requires an understanding of the uncertainties in a variety of stellar evolution processes as well as the uncertainty in the distance, reddening and composition. As a result, most studies focus only on the \textit{relative age} by assuming that stellar evolution calculations are accurate and using age determinations techniques that are relatively independent of distance and reddening. Here, we construct $20,000$ sets of theoretical isochrones through Monte Carlo simulation using the Dartmouth Stellar Evolution Program to measure the absolute age of the globular cluster M92. For each model, we vary a range of input physics used in the stellar evolution models, including opacities, nuclear reaction rates, diffusion coefficients, atmospheric boundary conditions, helium abundance, and treatment of convection. We also explore variations in the distance and reddening as well as its overall metallicity and $\alpha$ enhancement. We generate simulated Hess diagrams around the main-sequence turn-off region from each set of isochrones and use a Voronoi binning method to fit the diagrams to HST ACS data. We find the age of M92 to be $13.80\pm 0.75$ Gyr. The $5.4\%$ error in the absolute age is dominated by the uncertainty in the distance to M92 ($\sim 80\%$ of the error budget); of the remaining parameters, only the total metallicity, $\alpha$ element abundance, and treatment of helium diffusion contribute significantly to the total error.

arXiv comment15 Pages, 14 Figures, 2 Tables; Accepted for Publication AJ

References in corpus (39)

• The Dartmouth Stellar Evolution Database
• A large stellar evolution database for population synthesis studies. I. Scaled solar models and isochrones
• Low Temperature Opacities
• Adaptive spatial binning of integral-field spectroscopic data using Voronoi tessellations
• Gaia Early Data Release 3: The astrometric solution
• The NextGen Model Atmosphere grid for $3000\le \Teff \le 10000\K$
• Gaia Early Data Release 3: Parallax bias versus magnitude, colour, and position
• Solar fusion cross sections II: the pp chain and CNO cycles
• Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM
• Intrinsic iron spread and a new metallicity scale for Globular Clusters
• Element Diffusion in the Solar Interior
• The ACS Survey of Galactic Globular Clusters. I. Overview and Clusters Without Previous HST Photometry
• The ACS Survey of Galactic Globular Clusters. VII. Relative Ages
• The ACS Survey of Galactic Globular Clusters. XII. Photometric Binaries along the Main-Sequence
• An ACS Survey of Globular Clusters V: Star Catalog for Each Cluster
• The effects of He I 10830 on helium abundance determinations
• NACRE II: an update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number $A<16$
• Distances, ages, and epoch of formation of globular clusters
• The Quenching of the Ultra-Faint Dwarf Galaxies in the Reionization Era
• A Globular Cluster Metallicity Scale Based on the Abundance of Fe II
• Homogeneous age dating of 55 Galactic globular clusters. Clues to the Galaxy formation mechanisms
• Standard and Non-Standard Plasma Neutrino Emission Revisited
• Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey
• Stellar mass and age determinations - I. Grids of stellar models from Z=0.006 to 0.04 and M=0.5 to 3.5 Msun
• The Fossil Record of Two-phase Galaxy Assembly: Kinematics and Metallicities in the Nearest S0 Galaxy
• Not All Stars Are the Sun: Empirical Calibration of the Mixing Length for Metal-Poor Stars Using One-dimensional Stellar Evolution Models
• The Sparkler: Evolved High-Redshift Globular Clusters Captured by JWST
• The proton-proton weak capture in chiral effective field theory
• Heavy Element Dispersion in the Metal-Poor Globular Cluster M92
• The 14N(p,gamma)15O reaction studied with a composite germanium detector
• The OPAL Equation of State and Low Metallicity Isochrones
• Constraints on the Distance Moduli, Helium and Metal Abundances, and Ages of Globular Clusters from their RR Lyrae and Non-Variable Horizontal-Branch Stars. I. M3, M15, and M92
• Uncertainty quantification for proton-proton fusion in chiral effective field theory
• No Heavy Element Dispersion in the Globular Cluster M92
• On the absolute age of the Globular Cluster M92
• Testing Metal Poor Stellar Models and Isochrones with HST Parallaxes of Metal Poor Stars
• New Insight into the stellar mass function of Galactic globular clusters
• A Differential Abundance Analysis of Very Metal-Poor Stars
• The Age of the Universe

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