OPTICAL AND ELECTRON INTERACTIONS WITH METASTABLES.
COLUMBIA UNIV NEW YORK PLASMA LAB
Pagination or Media Count:
Afterglow plasmas are optically pumped with broadband radiation produced by a xenon flash lamp. The neon metastable concentration is decreased to less than 50 percent during the pumping, and a net depopulation results at the conclusion of the flash. A depopulation of the helium metastable is seen only during the pumping flash. By optically pumping neon metastables to the lower laser level, the laser lines 6328A and 1.15 microns are quenched. Amplification of the 1.15 micron laser line is observed when the population of the upper laser level is increased by selectively pumping neon metastables. Metastable collisions with heated electrons also result in a depopulation of the neon concentration. With further heating, the electrons gain enough energy to increase the metastable population by colliding with neutral neon atoms. Biondis theory on ionizing collisions is examined while controlling the metastable population with optical pumping. The experimental data support the theory that metastablemetastable collisions are an important ionization process in an afterglow. Author
- Lasers and Masers
- Plasma Physics and Magnetohydrodynamics