Investigation of the parameters of a nonstationary arc spot on a copper cathode by the thermospectroscopic method. I. Current density

A new procedure of determination of the effective density of the current in a nonstationary arc spot with the use of thermophysical and spectroscopic measurements has been proposed and tested. The procedure is based on recording of the critical cathode temperature corresponding to the instant of sharp increase in the intensity of the CuI λ = 5218 Å atomic spectral line, which coincides with the beginning of intense emission of a copper vapor from the spot, according the hypothesis proposed. New results are compared to those obtained earlier by purely thermophysical methods.[PUBLICATION ABSTRACT]