POPULATION OF LOWER STATES OF CESIUM ATOMS IN A SHORT, LOW-VOLTAGE ARC.

The populations of the 6S ground state and the 6P, 5D lowest excited states of the cesium atom are found experimentally in a short, low-voltage arc in a cesium-filled diode. The measurements are carried out by the ″hook″ method with a two-beam interferometer at various cesium pressures and discharge currents. The distributions of the level populations in the diode gap are determined. The distribution of the excitation temperature for the lower states with respect to the ground state are compared with the free-electron temperature as determined from the shape of the 6P recombination continuum.