First, unlike field stars, clusters' constituent stars have essentially the same chemical composition, are at the same distance, and are probably coeval, yet provide a richness of varied stellar masses. Thus, many of the most annoying uncertainties that arise during any field star survey are removed. Second, an X-ray survey of many different aged clusters allows for the study of the evolution of coronal properties, which, together with optical data on stellar rotation and estimates of stellar mass, should give clues about the stars' internal structure.
Current debate includes the question of whether there is core-envelope rotational decoupling.
This model almost certainly requires saturation of the angular momentum loss rate in order to reproduce the distribution of observed rotational velocities. One of the most important issues that can be addressed through these studies is determining what parameters most affect the stellar X-ray luminosity function. The only way to further constrain the theoretical models is to continue obtaining data of this type. My graduate students and I are also involved in other stellar research projects. In one, we are attempting to determine the ages of Pic stars since this knowledge may play an important role in understanding whether planetary system formation is common.