High gain prediction for soft x-ray laser pumped by plasma pinch innitrogen capillary discharge

摘要

Pinching capillary discharge in nitrogen is investigated for the purpose of development of soft x-raylaser recombination pumping. Our computer model is used to describe the pinch dynamics and to estimate thetransient gain of the active medium created during the pinch decay. Optimization of the device is performed atfour-dimensional space of optional experimental parameters: peak value of the current, initial slope of thecurrent, radius of capillary and initial nitrogen pressure. The pressure optimized gain Gmax evaluated for theBalmer α transition is used as the optimization criterion. Pressure optimized gain Gmax= 0.1 cm -1 is evaluated forthe current profile of the present CAPEX-U experiment, whereas Gmax = 1.3 cm -1 is predicted if the initial slopeof the current is increased about two times.