INTERACTION OF LASER-RADIATION WITH A POROUS-MEDIUM AND FORMATION OF A NONEQUILIBRIUM PLASMA

A theory of the interaction of a powerful laser radiation pulse with a , low-density porous material is proposed, This theory describes satis factorily the experimental results, it is shown that internal evaporat ion of the solid components of such a material into the surrounding ca vities of the medium leads to interesting features of the interaction of a laser pulse with the medium: formation of a region of radiation a bsorption under conditions of increasing geometric opacity of the mate rial, volume absorption of laser radiation in the material of density higher than the critical plasma density, and formation of a nonequilib rium plasma with a preferentially healed ionic component. A hypothesis is put forward and justified that it should be possible to construct a powerful neutron source operating on the basis of laser excitation o f hydrothermal dissipation in a spatially structured medium.