Role of Recombination in Forming Charge Composition of Ions in Laser Plasma with the Mass Spectrometric Analysis of Solids

Abstract

UDC 543.51+53.08

 

Numerical experiment was carried out so as to investigate the process of expansion of a plasma clot of a complex composition into a vacuum. Assuming that the density and the temperature of the laser plasma are homogeneous for clot, the system of differential equations describing the expansion of the plasma clot considering inelastic processes was reduced to a system of ordinary differential equations for the ions of 5 different elements: Fe, Mn, Cr, Ni, Mo, with the charger z = 1, 2, 3, 4. The speed of motion of the boundary the plasma clot and its temperature depending on the time of expansion were determined. It is shown that when the recombination stops as a result of "quenching", the nonequilibrium plasma is created thermodynamically in which the residual degree of ionization and ion distribution at charge states depends on the initial parameters of the plasma T0, N0, R0. In the process of recombination, the dependence of ion distribution at the charge from the ionization potential is reduced.

 

Keywords: laser plasma, plasma clot, plasma expan-sion, mass spectrum, recombination of ions, singly or doubly charged ions, length of recombination.

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