Characterization of titanium laser‐produced plasmas

The development of a plasma environment that is appropriate for the study of laser‐plasma processes in laser‐fusion plasma is reported. A material (titanium) with medium atomic number (Z) was used to provide x‐ray measurements of radial and axial plasma symmetry as well as electron temperature. The electron density evolution was measured using stimulated scattering processes and odd half‐harmonic generation from probe lasers of different wavelengths. The plasmas were created by two‐sided irradiation of thin foils with 24 kJ of 351 nm laser light. When the peak electron density had decayed to about 4×10²⁰ cm⁻³, the density profile was estimated to have a full width at half‐maximum of 2 mm and the electron temperature was measured to be about 3 keV using K‐shell spectroscopy. Two‐dimensional computer simulations were found to reproduce some features of both electron density and temperature evolution.