Coordinated XTE Observations of Coronal Structure and Flares on the Rs CVn Binary Sigma(sup 2) CrB

This NASA grant supported my RXTE observing and data analysis during AO2. The research involved a 100 kilosecond observation of the active RS CVn binary sigma(sup 2) CrB obtained on 1997 March 11-13. This observation covered two orbits of the binary (2.5 days elapsed time) as part of a coordinated satellite and ground-based study of coronal structure and flaring within this system. Simultaneous data was obtained from the ASCA X-ray satellite and the Very Large Array radio telescope. The one month of effort funded for the PI was used to calibrate and analyze the RXTE data. Additional research effort on this project to lead to a final publication has been provided from LTSA and GSRP grants. An initial attempt was made to calibrate the RXTE data in May 1997 but the results were disappointing with poor background subtraction leading to a relatively noisy PCA light curve. Subsequently major improvements have been made in the calibration techniques for low count rate PCA data and we returned to Goddard Space Flight Center in February 1999 when we were able to produce vastly better calibrated data. The RXTE results are currently being integrated with the ASCA and VLA data and a paper should be submitted by the end of summer 1999.