Rothschild This award supports the PI, Richard Rothschild, two postdoctoral students and two graduate students of the University of Florida in a collaboration with Rudiger Staubert of the Institute for Astronomy at the University of Tuebingen, Germany. The research focus is on the analysis and interpretation of X-ray data from the Rossi X-ray Timing Explorer (RXTE). The U.S. team has a strong knowledge of the strengths and limitations of the data obtained from RXTE and the German team is strong in the development and use of advanced interpretive tools. Together, the two teams are in a unique position to use the raw X-ray data to answer current astrophysical questions. Specifically, the two groups will improve our understanding of processes associated with neutron stars and black holes.