TIME-RESOLVED PROFILES OF ELECTRON-DENSITY AND TEMPERATURE IN LASER-IRRADIATED CYLINDRICAL CAVITIES

Measurements are reported of the plasma electron density and temperatu re profiles in cylindrical cavities, transversely irradiated through a n off-center longitudinal slit. The temporal evolution of these quanti ties is determined from spatially and temporally resolved aluminum K-s hell spectra using a novel experimental setup. For 300 mum diameter cy lindrical cavities, the parameters of the ablating as well as of the c olliding plasma have been measured and cooling rates have been determi ned from the time-dependent electron temperature profiles. The cooling rates in the cylindrical cavities are found to decrease with increasi ng diameter and to be lowest for slab targets. This is attributed to e nhanced thermal conduction to the surrounding walls.