Novel Attempts to Realize an Innershell X-Ray Laser in Na

A planned experiment to realize an innershell x-ray laser in atomic sodium by pumping with the Zn x-ray laser at 21.2 nm, presently operated at the PALS laser facility, is presented. According to model calculations, a gain of more than 60 cm-1 is expected for a sodium density of 1016 cm-3 and the given pump laser data.