Open and Globular Cluster Ages Using Theoretical Isochrones
نویسندگان
چکیده
منابع مشابه
Globular cluster ages.
We review two new methods to determine the age of globular clusters (GCs). These two methods are more accurate than the classical isochrone fitting technique. The first method is based on the morphology of the horizontal branch and is independent of the distance modulus of the globular cluster. The second method uses a careful binning of the stellar luminosity function and determines simultaneo...
متن کاملGlobular Cluster Ages and Strömgren CCD Photometry
Strömgren uvby CCD photometry can be used in a variety of ways to constrain the absolute and relative ages of globular clusters. The reddening corrected v−y, c1 diagram offers the means to derive ages that are completely independent of distance. Very precise differential ages for clusters of the same chemical composition may also be determined from such 2–color plots, or from measurements of th...
متن کاملGlobular Cluster Ages and the Formation of the Galactic Halo
Main sequence turno magnitudes from the recent set of Yale isochrones (Chaboyer et al. 1995) have been combined with a variety of relations for the absolute magnitude of RR Lyr stars (Mv(RR)) to calibrate age as a function of the di erence in magnitude between the main sequence turn-o and the horizontal branch ( V HB). A best estimate for the calibration of Mv(RR) is derived from a survey of th...
متن کاملTheoretical vs . semi - empirical relative ages of globular clusters
Theoretical relative ages of galactic globular clusters have recently been challenged by a semi-empirical relation. It was used to point out that tested sets of iso-chrones were unable to reproduce the relation and yield internally inconsistent relative ages. We find that differential cluster ages derived with the isochrones by Salaris & Weiss (1998) are reliable and internally consistent. We a...
متن کاملModeling age and metallicity in globular clusters: a comparison of theoretical giant branch isochrones
In view of the important contributions of red giants to the integrated light in evolutionary synthesis calculations of old stellar populations in clusters and galaxies, we provide a comparison of theoretical isochrones computed from the Padova, Geneva, and Yale evolutionary tracks, respectively. Using the most recent version of the colorcalibrated library of theoretical stellar spectra by Lejeu...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 2000
ISSN: 0074-1809
DOI: 10.1017/s0074180900003156