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arXiv · 0711.4045

Fiducial Stellar Population Sequences for the u'g'r'i'z' System

James L. Clem·Don A. VandenBerg·Peter B. Stetson
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Abstract

We describe an extensive observational project that has obtained high-quality and homogeneous photometry for a number of different Galactic star clusters (including M 92, M 13, M 3, M 71, and NGC 6791) spanning a wide range in metallicity (-2.3<[Fe/H]<+0.4), as observed in the u'g'r'i'z' passbands with the MegaCam wide-field imager on the Canada-France-Hawaii Telescope. By employing these purest of stellar populations, fiducial sequences have been defined from color-magnitude diagrams that extend from the tip of the red-giant branch down to approximately 4 magnitudes below the turnoff: these sequences have been accurately calibrated to the standard u'g'r'i'z' system via a set of secondary photometric standards located within these same clusters. Consequently, they can serve as a valuable set of empirical fiducials for the interpretation of stellar populations data in the u'g'r'i'z' system.

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James L. Clem, Don A. VandenBerg, Peter B. Stetson. 2007-11-26. Fiducial Stellar Population Sequences for the u'g'r'i'z' System. https://doi.org/10.1088/0004-6256%2F135%2F2%2F682

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