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The results of the experiments on Z-pinch produced from wire arrays performed on the facility Angara-5-1 are presented. The models of liner implosion, i.e. prolonged plasma production have found their confirmation. Estimation based on our experimental data show that W wire cores are heterogeneous. The velocity of core expansion is determined by energy deposited at the first nanoseconds after current start. The effect of the inner array on the current distribution in the region between the arrays has been revealed. The «lost mass » was measured at initial radius of array at the moment of X-ray pulse maximum. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Brief review of our recent results concerning prolonged plasma production (P³) in multiwires arrays and its influence on their dynamics in pulse power facilities is presented. P³ means that owing to overheating effects hot plasma with high conductivity is being produced from the relatively cold material almost during the whole period of current rising. P³ results in formation of a plasma shell with a low aspect ratio and without any skin effect. It means that magnetic flux and electric current are distributed more or less uniformly along the shell and there is no magnetic piston. The latter fact is responsible for the more stable implosion of the plasma. P³ is unavoidable effect for initially cold liners of all types in pulse power facilities, and it is useful for production of high power X-ray pulses with multiwires arrays because the process of P³ leading to more stable implosion is well controlled in this case due to well defined periodic structure of the array. Theoretical evaluation of rate of plasma production is obtained, and it is compared with experiments. Simple simulation of plasma dynamics during implosion of multiwire arrays with P³ is presented. Combining of such simulation with probe magnetic measurements inside cylindrical liners we obtain a certain information about dependence of the plasma production rate on time and about characteristics of depletion of plasma source. It appears that process of the depletion may be rather gradual, so that some amount of plasma is being placed at initial array position even till the moment of X-ray pulse maximum. It may lead to partial shunting of electric current and to some depression of X-ray pulse intensity. These results discover new opportunities to control plasma implosion and X-ray pulse parameters. [ABSTRACT FROM AUTHOR]

The study of the wire array implosion on installation Angara-5-1 is devoted. Magnetic probes and the x-ray backlighting technique were used to investigate a current and mass distribution during the implosion. The experimental data confirm the concept of prolonged plasma production: the long time of implosion the hot plasma flows from dense fixed wire cores and is accelerated by the Lorentz force to the array center together with frozen magnetic field. [ABSTRACT FROM AUTHOR]