GT Observations of Active Cool Stars: UX Ari

GTUX Ari is a very active RS CVntype binary system that has produced some ofthe most energetic coronal flares seen on such stars. We propose to observe UX Ari for 40 ks to investigate the composition of its quiescent corona indetail, and, if a flare is seen, to follow the temperature, density, abundance,and plasma velocity histories during the evaporation and cooling processes indetail with the RGS and the EPICs. To avoid saturation, the pn and one MOScamera will be used in TIMING mode, both with the medium filter. The OM willobserve with the UVW2 filter. Coordinated radio VLA and spatially resolvedVLBA/VLBI as well as optical observations are planned to study the geometry andenergy balance of UX Ari.s atmosphere. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]