Vacuum arc anode plasma. I. Spectroscopic investigation

Journal Article · Sat Nov 01 00:00:00 EST 1975 · J. Appl. Phys., v. 46, no. 11, pp. 4750-4757

DOI:https://doi.org/10.1063/1.321552· OSTI ID:4126181

Bacon, F M

A spectroscopic investigation was made of the anode plasma of a pulsed vacuum arc with an aluminum anode and a molybdenum cathode. The arc was triggered by a third trigger electrode and was driven by a 150-A 10-$mu$s current pulse. The average current density at the anode was sufficiently high that anode spots were formed; these spots are believed to be the source of the aluminum in the plasma investigated in this experiment. By simultaneously measuring spectral emission lines of Al I, Al II, and Al III, the plasma electron temperature was shown to decrease sequentially through the norm temperatures of Al III, Al II, and Al I as the arc was extinguished. The Boltzmann distribution temperature T/ subD/ of four Al III excited levels was shown to be kT/subD//e=2.0plus-or- minus0.5 V, and the peak Al III 4D excited state density was shown to be about 5times10$sup 17$ m$sup -3$. These data suggest a non-local-thermodynamic- equilibrium (non-LTE) model of the anode plasma when compared with the Al$sup 3+$ production in the plasma. The plasma was theoretically shown to be optically thin to the observed Al III spectral lines. (auth)

• Research Organization: Sandia Laboratories, Albuquerque, New Mexico 87115
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-009037
• OSTI ID: 4126181
• Journal Information: J. Appl. Phys., v. 46, no. 11, pp. 4750-4757, Other Information: Orig. Receipt Date: 30-JUN-76
• Country of Publication: United States
• Language: English

Related Subjects

N70400* -Physics-Controlled Thermonuclear Research- Kinetics (Experimental)
700104* -Fusion Energy-Plasma Research-Plasma Kinetics- Experimental
*ELECTRIC ARCS- PLASMA DIAGNOSTICS
*PLASMA DIAGNOSTICS- EMISSION SPECTROSCOPY
ALUMINIUM
ALUMINIUM IONS
ELECTRON TEMPERATURE
EMISSION SPECTRA
EXCITED STATES
OPTICALLY THIN PLASMA