Lyrae Variables in Globular Clusters and Nearby
نویسنده
چکیده
I point out that the Oosterhoff dichotomy for globular cluster and field RR Lyrae (RRL) stars may place the strongest constraints so far on the number of dwarf spheroidal-like protogalactic fragments that may have contributed to the formation of the Galactic halo. The first calibration of the RRL period-luminosity relation in I, J , H, K taking evolutionary effects into account is provided. Problems in the interpretation of RRL light curves and evolutionary properties are briefly reviewed.
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