Powerful CMD: A Tool for Colour-Magnitude Diagram Studies
  We present a new tool for colour-magnitude diagram (CMD) studies,
$Powerful~CMD$. This tool is built on the basis of the advanced stellar
population synthesis (ASPS) model, in which single stars, binary stars,
rotating stars, and star formation history have been taken into account. Via
$Powerful~CMD$, the distance modulus, colour excess, metallicity, age, binary
fraction, rotating star fraction, and star formation history of star clusters
can be determined simultaneously from observed CMDs. The new tool is tested via
both simulated and real star clusters. Five parameters of clusters NGC6362,
NGC6652, NGC6838 and M67 are determined and compared to other works. It is
shown that this tool is useful for CMD studies, in particular for those with
the data of the Hubble Space Telescope (HST). Moreover, we find that the
inclusion of binaries in theoretical stellar population models may lead to
smaller colour excess compared to the case of single star population models.
