An Investigation of Mechanisms of Initiation of Laser-Supported Absorption (LSA) Waves
Semi-annual rept. 15 Jul 1974-14 Jan 1975
BATTELLE COLUMBUS DIV OH
Pagination or Media Count:
Additional experimental results of a study of LSD-wave initiation processes are reported. The first measurements of delay time to initiation on nonmetallic materials are presented. In metallic studies, target emission of electrons from aluminum 2024, lead, and tungsten surfaces were recorded at atmospheric pressure prior to LSD-wave initiation. No surface damage was observed on the tungsten surface at 2000X in SEM inspections after irradiation, while lead and aluminum exhibited defect-oriented damage. Time-resolved spectroscopy experiments with aluminum 2024 revealed a dramatic drop in the ionized aluminum vapor emissions above the air pressure threshold for LSD-wave initiation 5-10 torr at 3.2 x 10 to the 8th power wattcm squared.
- Lasers and Masers
- Plasma Physics and Magnetohydrodynamics