Deexcitation and recombination processes involving doubly excited levels in high density plasma

Enhancement of deexcitation and recombination from excited ions in dense plasma is considered for lithiumlike ions. The former process is caused by the thermal population in doubly excited levels of berylliumlike ions and their autoionization, and the latter is the collisional-radiative recombination which has been well established for the ground state ions. We have estimated the effective rate coefficients for these processes by adopting various approximations. We incorporate them into our collisional-radiative model for the lithiumlike aluminum recombining plasma. The population inversion and the gain of the 3d2D-5f2F laser transitions are calculated. copyright 1996 American Institute of Physics