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Metallicity and age of M31 globulars from automated fits to theoretical spectra

Published online by Cambridge University Press:  01 December 2006

Ruth C. Peterson*
Affiliation:
UCO/Lick Observatories and Astrophysical Advances
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Abstract

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We are calculating stellar spectra for types A through K using Kurucz codes, Castelli models, and Kurucz laboratory lines plus guessed identifications for other lines in the spectra. Weighted coadditions of these spectra are being constructed to match spectra observed in integrated light of old stellar systems such as elliptical galaxies and globular clusters. Grids of theoretical spectra, both stellar and composite, that include an enhancement of light elements and span a wide metallicity range will be calculated over 2200Å–9000Å, and will be archived on MAST at the Hubble Space Telescope website. Here we summarize our results and describe how we automate the fit to our grid of an observed high-resolution stellar or globular-cluster spectrum, to determine the stellar parameters or to break the age-metallicity degeneracy.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2007

References

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