Colliding plasmas in laser irradiated cavities studied with soft x-ray interferometry

Electron density maps of dense converging plasmas created by laser irradiation of semi-cylindrical and V--shaped targets at I = 1 x 10$^{12}$ W/cm$^{2}$ were obtained with soft x-ray laser interferometry ($\lambda $ = 46.9 nm). In the case of the cylinders, the plasma expands off the target surface converging in a focal region, creating a concentrated plasma where the electron density build-up exceeds 1 x 10$^{20}$ cm$^{-3}$. The plasma in the V-shaped targets concentrates along the symmetry plane of the target where collisions redirect the plasma forming, early on in the evolution, a narrow jet-like plasma. The measurements were compared with simulations obtained using the code HYDRA.