Superspherical cumulation. Converging shock waves with amplitudes increasing faster than in spherical cumulation

Experimental, numerical, and theoretical investigations are made of a gas f low generated by a pulsed high-current discharge in an axisymmetric cavity bounded by a spherical lens adjacent to a flat plate. It is shown that the shock wave forming in the discharge and converging toward the axis is accel erated and amplified as it converges. The amplitude of the shock wave incre ases faster than does that of a spherical converging shock wave. (C) 1999 A merican Institute of Physics. [S1063-7842(99)00203-2].