This award supports Dr. Donald Winget and others (including graduate students) of the University of Texas at Austin to collaborate in astrophysics research with Dr. Michel Breger and his group at the Institute of Astronomy, University of Vienna. The two research groups have been operating two independent international telescope networks for measuring features of stars of very different ages: the Delta Scuti Network (Austria) and the Whole Earth Telescope Network (Texas). The networks are similar in their goal of completely resolving the brightness variations of complex pulsating stars into their component frequencies for seismological study of stellar interiors. However the networks are currently completely different and complementary in the frequency domains that they cover. The goal of the collaboration proposed for support here is to integrate the two networks and software, personnel, and analytical methods. The participants will then be able to measure simultaneously several selected stars in extreme states of stellar evolution. The work that provides the basis for this proposal has broken new ground in the field of stellar physics through studies of the Sun. The techniques and approach being employed have opened a whole new level of study of stellar dynamics and evolution, by probing the internal structure of stars using networks of observations and applying seismological theory. The expanded collaboration offers a unique opportunity to advance this research.
