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Age and Metallicity Estimation of Globular Clusters from Stromgren Photometry

K. Rakos·J. Schombert
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Abstract

We present a new technique for the determination of age and metallicity in composite stellar populations using Stromgren filters. Using principal component (PC) analysis on multi-color models, we isolate the range of values necessary to uniquely determine age and metallicity effects. The technique presented herein can only be applied to old (tau > 3 Gyrs) stellar systems composed of simple stellar populations, such as globular clusters and elliptical galaxies. Calibration using new photometry of 40 globular clusters with spectroscopic [Fe/H] values and main sequence fitted ages links the PC values to the Strömgren colors for an accuracy of 0.2 dex in metallicity and 0.5 Gyrs in age.

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K. Rakos, J. Schombert. 2004-12-08. Age and Metallicity Estimation of Globular Clusters from Stromgren Photometry. https://doi.org/10.1086/427987

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