116-NM H-2 LASER PUMPED BY A TRAVELING-WAVE PHOTOIONIZATION ELECTRON SOURCE

We report the use of a photoionization electron source to pump a 116-nm laser in the Werner band (C1-PI-u --> X1-SIGMA-g+) of molecular hydrogen. The laser is pumped by free electrons which are created by photoionizing molecular hydrogen with soft x rays from a traveling-wave laser plasma. We show that even though the free electrons have an average temperature of approximately 10 eV, the lasing hydrogen molecules retain an ambient temperature of approximately 0.01 eV. This allows an extrapolated small-signal gain of exp(43), with a 1064-nm pumping energy of 580 mJ in 200 psec.