[en] The properties of optically-excited Hg/NH₃ and Hg/ND₃ mixtures have been studied as a function of mercury pressure in the range 1 to 40 torr. At low mercury pressures, less than or equal to 1 torr, the well-known uv emission band due to HgNH₃* is dominant; this regime has been investigated extensively over the past ten years. However, at higher pressures the uv band disappears and is replaced by a strong green emission band, centered near 500 nm. From a detailed study of the spectral and temporal characteristics of the green band, it is concluded that it arises from the formation of the Hg₂NH₃* (or Hg₂ND₃*) excited molecular complex. The lifetime of this exciplex has been measured and is found to be 3.8 μsec (+- 25%). Because of interest in the system as a potential energy storage laser medium, optical transmission measurements have been carried out at selected wavelengths. Net absorption has been observed across the green band at high mercury density, as well as in the uv band in the low density regime

[en] In an effort to reliably extend the understanding of KrF* lasers, we collected specific, detailed experimental data and carried out theoretical calculations to explore and document those issues we identified as likely to be important in the short pulse operating regime. These included the effects of: (1) fuel burnup, (2) electron quenching, (3) gain/absorption at high current densities, (4) photoionization, (5) accessibility of the lying levels of KrF by laser flux, (6) temperature on fluorescence efficiency