J. Phys. IV France 04 (1994) C4-101-C4-105
Laser plasma formation in metals vapour : kinetic approachV. MAZHUKIN1, I. GUSEV1, I. SMUROV2 and G. FLAMANT3
1 Institute of Mathematical Modeling, Russian Academy of Sciences, Miusskaya Square 4, 125047 Moscow, Russia
2 Ecole Nationale d'Ingénieurs de Saint-Etienne, 58 rue Jean Parot, 42023 Saint-Etienne cedex 2, France
3 Institut de Science et de Génie des Matériaux et Procédés, CNRS, BP. 5, Odeillo, 66125 Font-Romeu cedex, France
The break-down of metals vapour (Al, Cu) are simulated near the break-down threshold values of laser radiation. The approximations of collision-radiation model are used, including the detail kinetics of exited states with radiation and collision transitions, step-by-step ionisation process, unexitation and recombination. Energy balance is based on two-temperature approximation : for electrons and for heavy particles. It is shown that the particles concentration in exited states and plasma species composition differ rather from Saha-Boltzmann's distribution. Strong dependence of the break-down threshold intensity on initial temperature of neutral and charged particles is shown.
© EDP Sciences 1994