Effect of collision between laser-produced plasma flows in conical targets on plasma parameters in final stages of expansion

Charge, kinetic and geometric parameters of an ion component in the laser-produced plasma have been investigated at final expansion stages under radiation focusing onto a lead target with a hollow cone. Dependences of these parameters on the apex angle of cone have been determined and comparison with the plane target case has been made. The measurements have been performed by probe and the mass-spectrometer methods. The results obtained show that a narrow-jet plasmoid with a high degree of ionization is feasible due to target shape and radiation focusing conditions optimization. A probable mechanism of collision process influence on resulting plasma parameters is discussed