Acoustical Resonances in Modulated Xenon and Krypton Compact Arc Lamps

Abstract

When the dc current through a compact arc lamp is modulated, are instabilities appear at discrete frequencies. At some of these frequencies, the instabilities are sufficiently severe to extinguish the lamp. The primary frequency at which the arc bows to the side and tends to extinguish has been studied as a function of bulb diameter and current for xenon and krypton lamps. A theoretical treatment of acoustical resonances is presented and it is quantitatively shown that the experimentally determined primary extinction frequency coincides with the primary acoustical resonance. Furthermore, the dependence of the primary extinction frequency on bulb diameter, temperature, pressure, and molecular weight fit the acoustical resonance theory.