Towards nitrogen recombination soft X-Ray Laser scheme in a capillary discharge z-pinch

In recent years z-pinch configuration is considered for implementing a nitrogen recombination X-Ray Laser at lambda approximate to 13.4nm. The required plasma conditions at the pinch time are T-e similar to 140eV and N-e similar to-10(20)cm(-3). Lasing can occur after the plasma cools to T-e < 60eV, in a time scale of a few nanoseconds (< 5nsec). A capillary discharge z-pinch apparatus was built (I-max approximate to 60kA, tau(1/4)=70nsec), and examined by means of radiation measurements with filtered X-Ray diode (XRD). By using different filters it is possible to identify the emission from He-like and H-like nitrogen. We show that at the pinch time the electron temperature is well above 80eV, and the total cooling period, to T-e < 60eV, is shorter than 5nsec. Future complementary XRD and spectroscopic measurements are being planned.