抄録
The copper vapor density as well as the arc temperature of a 10 A D. C. copper arc in air were determined from the space-resolved absolute spectral intensity obtained from spectral-images photographed in the wavelength range of 4000-6000 A without using any other information such as the electron density. The well-known Boltzman plots were drawn and a straight line was obtained of which slope and intersection with the ordinate axis give the arc temperature and the copper vapor density, respectively. The electron current density was obtained based on the electron density calculated from the Saha equation under the assumption of the thermal equilibrium. The obtained radial distribution of the electron current density was integrated to obtain an arc current 10.2 A which was in good agreement with that supplied through the external electric circuit.
