Spatially resolved argon microplasma diagnostics by diode laser absorption

Argon metastables in HiPIMS: time-resolved tunable diode-laser diagnostics

Time resolved Tunable Diode-Laser Absorption Spectroscopy (TD-LAS) measurements were performed on the argon metastable (Ar) level 3s3p(P°3/2)4s excited at 801.478 nm, in the dense plasma region in front of the magnetron target in a high power impulse magnetron sputtering (HiPIMS) discharge. From the Doppler profile the evolution of the temperature and density were derived during the pulse as we...

Diagnostics of an argon arcjet plume with a diode laser.

The diode-laser absorption technique was applied for simultaneous velocity and temperature measurements of an argon plume exhausted by an arcjet. The Ar I absorption line at 811.531 nm was taken as the center absorption line. The velocity and the temperature were derived from the Doppler shift in the absorption profiles and the full width at half-maximum of the plume absorption profile, respect...

Laser propagation and energy absorption by an argon spark

The laser propagation and energy absorption of an argon spark induced by a laser at different pressures is investigated. 8 ns pulses from a frequency-doubled Q-switched Nd:YAG laser are used to create the spark. The pressure of the argon is varied from 1 atm to 10 Torr. Significant energy absorption by the plasma is observed at high pressures (.100 Torr) while there is negligible absorption whe...

Tunable Diode Laser Absorption Spectroscopy of Oxygen

Balloon-borne tunable diode laser absorption spectrometer

A balloon-borne tunable diode laser absorption spectrometer capable of in situ measurement of the concentrations of several stratospheric trace gases simultaneously in the same parcel of air is described. Laboratory tests show present detection limits of 1.5 ppbv for NO and 0.5 ppbv for N02 under stratospheric conditions. This instrumentwas flown in July 1983 to make the first tunable diode las...