IUE Studies of X-Ray K-M Dwarfs

K-M dwarfs exhibited a large range of coronal X-ray luminosity Lx in results of the P.I.'s programs with the HEAO-2 (Einstein) observatory. It has been difficult to correlate Lx with any one of several parameters such as rotation, close-binary membership, or age, but a promising lead is chromospheric Ca II emission. The ultraviolet provides better indicators of the activity of the chromospheric-coronal transition region, and the plan is to observe the specified X-ray sample with the IUE so as to establish new correlations between the ultraviolet spectra, X-ray luminosity, and various optical parameters. The P.I.'s X-ray sample is drawn from the nearest K-M dwarfs so it also provides the brightest stars of given type for IUE study. A paper will be published to present at least the complete IUE observational results, and it will constitute the principal deliverable work.