Study of recombination processes during the expansion phase of titanium-plasma produced by picosecond Nd:glass laser radiation

An investigation of the plasma dynamics during its expansion phase is presented. The analysis is based on a numerical model, which considers the adiabatic plasma expansion as well as a three-body recombination process as the main source for plasma cooling. The result shows that a fast energy transfer between electrons and ions is observed during the early stage of plasma expansion. Three-body recombination process exhibits a pronounced effect leading to a "freezing" feature in the average charge states of heavy particles. This process seems to control the fractional population of ionic species at the end of the expansion phase. (C) 2003 Elsevier Science B.V. All rights reserved.