Time behavior of second-positive emissions from a fast-discharge N2+SF6 laser

The time behavior of spectrally resolved N2 second-positive emissions recently observed in our fast-discharge N2+SF6 laser reveals some surprising features that cannot be explained on the basis of SF6-catalyzed vibrational relaxation or collisional quenching of the lower-laser-level B3Πg. Instead, they suggest the existence of an extremely fast excitation process for the upper-laser-level C3Πu involving SF6 as an intermediary, although the kinetic path for such a process remains unclear.