Intensities of some spectral lines from hollow-cathode lamps

Abstract

The relationship between spectral line intensity I and discharge current i is examined as part of an investigation of low pressure (1–20 Torr) hollow-cathode discharges in neon, for various cathode dimensions. An equation, I=Ai(1 +Ci)/(1 +Bi), deduced by balancing likely excitation and de-excitation processes, can be fitted within the limits of experimental accuracy to measured I versus i graphs. Here, A depends on one-stage excitation, C on the relative importance of two- and one-stage excitation, and B on the relative importance of collisional and radiative de-excitation. The values of B and C for individual lines, and their dependence upon pressure and upon cathode dimensions, together with the possible role of self-absorption, are discussed.