CORNELL UNIVERSITY PROJECT TITLE: X-RAY SPECTROSCOPIC STUDIES OF RADIATIVE COLLAPSE IN X-PINCH PLASMAS THE CORNELL UNIVERSITY TEAM WILL CARRY OUT DENSE Z-PINCH EXPERIMENTS USING THE 400 KA XP PULSED POWER EXPERIMENTS BY PASSING THE CURRENT THROUGH A SHORT LENGTH OF WIRE THAT FIRST RESISTIVELY EXPLODES THE WIRE, AND THEN IMPLODES IT TO VERY HIGH DENSITY AND CAUSES IT TO PRODUCE A VERY SHORT (<0.1 NS) X-RAY BURST FROM A ~ 1 ΜM SOURCE CALLED A MICRO-PINCH. DIAGNOSTIC INSTRUMENTS WILL INCLUDE CRYSTAL SPECTROGRAPHS, X-RAY STREAK CAMERAS AND OTHER ELECTRICAL AND X-RAY DEVICES. THEY WILL CARRY OUT COMPUTER SIMULATIONS AND DETAILED ATOMIC PHYSICS CALCULATIONS TO ENABLE UNDERSTANDING OF THE X-RAY SPECTRA THAT ARE OBTAINED. PROJECT OBJECTIVES THE PRINCIPAL SCIENTIFIC OBJECTIVE OF THIS PROJECT IS TO DETERMINE IF THE PROCESS CALLED RADIATIVE COLLAPSE PLAYS A SIGNIFICANT ROLE IN THE FORMATION OF THE TINY, HOT, INTENSELY RADIATING DENSE PLASMA MICRO-PINCHES IN THE CURRENT-CARRYING PLASMA CONFIGURATION KNOWN AS AN X-PINCH. CORNELL WILL ADDRESS THIS QUESTION USING A COMBINATION OF HIGH TIME-RESOLUTION EXPERIMENTS USING A PULSED POWER MACHINE AND SEVERAL VERY HIGH TIME RESOLUTION X-RAY DIAGNOSTIC INSTRUMENTS, COMPUTER SIMULATIONS OF X-PINCH IMPLOSION DYNAMICS, AND DETAILED ATOMIC PHYSICS AND X-RAY SPECTROSCOPY CALCULATIONS. IF RADIATIVE COLLAPSE TAKES PLACE, THE RADIATION SPECTRUM AS A FUNCTION OF TIME SEEN ON THE X-RAY STREAK CAMERA WILL HAVE DIFFERENT CHARACTERISTICS THAN IF THE PLASMA IMPLOSION IS PURELY A RESULT OF HYDRO-MAGNETIC FLUID INSTABILITIES.