Role of focusing in heat-conduction heating of a plasma by high-power laser radiation

A theoretical analysis is given of the process of heating of a plasma by a spherical electron thermal wave generated by an ultrashort (10^–11–10^–12 sec) laser pulse incident on a solid target. Analytic expressions are obtained for the ion temperature, the volume, and the lifetime of a hot plasma. The neutron yield is calculated for a deuterium plasma and for a lithium deuteride plasma as a function of the absorbed energy and the area on which the laser radiation is focused.