Submicrosecond pulses from a hydrogen-fluorine laser with high energy density and quantum efficiency

Submicrosecond pulses have been obtained from a photochemical H
2
-F
2
laser with a chemical efficiency of 0.5 percent. Energy densities of 6 J l
^-1
were obtained from 60 torr (at 213 K) of a stoichiometric H
2
-F
2
mixture stabilized with 5 mole-percent O
2
. Laser output energy and the reciprocal of the pulsewidth were both proportional to the gas pressure. Actinometry showed that the laser energy output was 16.6 times the energy necessary to provide F atoms for initiation. Time-resolved spectra revealed excitation up to
\upsilon' = 6
.