Research On The Z-pinch Effect And Neon-like Argon Soft X-ray Laser

Soft x-ray laser possessed many specifications, such as short wavelength, monochrome, short pulse duration, while no other light source could have all of them simultaneously. Thus, soft x-ray laser could be utilized in the applications, such as dense plasma diagnose. Among all of the small scale soft x-ray laser schemes, capillary discharge soft x-ray laser has advantages in the equipment scale, building and running cost, single shot energy of laser, repetition rate and so on. As a result, the capillary discharge soft x-ray laser is the most promising scheme for large scale application in laboratories.The researches on capillary discharge soft x-ray laser have been conducted in both experiment and theoretical simulation. The Z-pinch effect of capillary discharge soft x-ray laser has been simulated. In this dissertation, we have built a new capillary discharge soft x-ray laser equipment with high amplitude main current, after the achievement of capillary discharge soft x-ray laser with low amplitude main current.In the theoretical study, a one dimensional cylindrical symmetry Lagrangian magneto-hydrodynamics(MHD) code has been written. Then it has been utilized in the simulations of the Z-pinch process with different initial pressures and different inner diameters of capillary. The temporal and spatial distribution of plasma parameters, such as the electron temperature, the electron density and the Ne-like Ar ion density, had been simulated with the MHD code. The discussion has been conducted on the Z-pinch process with different inner diameters and initial pressures. The difference between the gain coefficients with the 3.2 mm and 4.0 mm inner diameter alumina capillaries has been analysed with the simulated results.The experimental research of capillary discharge soft x-ray laser has been conducted with the high amplitude main current generator. At the same time, the research has been conducted on the evolution of plasma condition and the abundances of Ar atom and Ar+ ion during the pre-ionization process. The temporal evolutions of spontaneous radiation and time integrated spectrum from the pre-ionzed plasma have been measured, and the diagnostics of pre-ionzed plasma has been conducted. The influence of pre-ionized plasma on the soft x-ray laser has been analysed. The experiments have been conducted with the 3.2 mm and 4.0 mm inner diameter alumina capillaries under different initial pressures, pre pulse and main pulse delay time and the main current of 26 k A. Then, the optimum experimental parameters have been acquired for both capillaries. The gain coefficients are 0.86 cm-1and 1.3 cm-1 with the optimum experimental parameters for the 4.0 mm and 3.2 mm inner diameter alumina capillaries, respectively.The researches have been conducted on the pulse duration and the divergence angle of capillary discharge 46.9 nm laser. First, the durations time of laser pulse have been measured at different lengths of the 3.2 mm and 4.0 mm inner diameter alumina capillaries under optimum initial pressure. Then the evolution of pulse duration over length had been simulated. Based on the simulations, the evolutions of the pulse duration have been analyzed. At the same time, the pulse durations were measured under different initial pressures. The experimental results were analyzed with the MHD and pulse duration simulations. On the other hand, the spatial distributions of laser intensity were measured with Soft x-ray flatfield spectrometer under different initial pressures and the 3.2 mm and 4.0 mm capillaries, and the divergence angles of laser were measured and analyzed.The researches on the Ne-like Ar 69.8 nm C line and 72.6 nm E line soft x-ray laser have been conducted with the capillary discharge scheme. The lower amplitude main current and lower initial pressure of Ar result in higher electron temperature and lower density of electron during the Z-pinch effect. These plasma conditions are conducive to the Ne-like Ar 69.8 nm C line and 72.6 nm E line laser.In the experiment, the Ne-like Ar 69.8 nm C line and 72.6 nm E line lasers were observed in the experiments, with the main current of 12 k A and the initial pressure of 14 Pa. On the other hand, the plasma conditions were simulated with the MHD code under the same initial parameters in the 69.8 nm laser experiment, then the simulations were analyzed.The Z-pinch plasma conditions and their influence on the soft x-ray laser were analyzed in this dissertation. And the experimental and theoretical results shown in this dissertation could promote the development of capillary discharge soft x-ray laser.