MODIFIED ATOMIC TRANSITION RATES BY PLASMA ION FIELDS

Atomic transition rates used in plasma modeling are themselves affecte d by the plasma environment. The effect of plasma ions is conveniently represented by a time-dependent electric field, and the resulting cha nges in the various rates by this field are presented as plasma enhanc ement factors, in compact and user friendly forms. They apply to radia tive deexcitation, collisional excitation and deexcitation, radiative recombination, collisional ionization, three-body recombination and An ger ionization. The enhancement factors are scaled in terms of three p arameters; principal quantum number(s) n of atomic bound state(s), pla sma density (N) over tilde = N/Z(3) and (ionic) temperature (T) over t ilde(p) = T-p/(mu(p)Z(2)), where Z is the charge of the ionic core. Al though the enhancement factors that involve high Rydberg states are as large as 10(3) in the range of interest of (N) over tilde and (T) ove r tilde(p), their effects on the plasma kinetics may be small since th e atomic rates strongly decrease with n and the role of high Rydberg s tates is suppressed by plasma field ionization and by Debye shielding.