New Methods for Determining the Ages of PMS Stars
arXiv:0909.1746 · doi:10.1017/S1743921309031755
Abstract
We present three new methods for determining the age of groups of pre-main-sequence stars. The first, creating empirical isochrones allows us to create a robust age ordering, but not to derive actual ages. The second, using the width of the gap in colour-magnitude space between the pre-main-sequence and main-sequence (the radiative convective gap) has promise as a distance and extinction independent measure of age, but is as yet uncalibrated. Finally we discuss tau-squared fitting of the main sequence as the stars approach the terminus of the main sequence. This method suggests that there is a factor two difference between these "nuclear" ages, and more conventional pre-main-sequence contraction ages.
6 pages, 3 figures
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