Light-effect in chlorine under electrical discharge: change of the wave form due to irradiation

Abstract

Previous work on this phenomenon showed that a current decrease δi is produced by irradiation of chlorine and other gases referred to the rectified mean r.m.s. values of i under different conditions; changes in the corresponding current-structure and its time-delineation are revealed by a cathode ray oscillograph. An iron core step-down transformer was introduced in series with an A.C. indicator. Its secondaries Were connected to one pair of the deflecting plates in the oscillograph; the other pair was connected to the time-sweep potential. With but a moderate amplifier gain on each of the plate pairs and the usual adjustments, the oscillograph revealed, besides the frequency of the A.C. supply, a remarkably large number of higher frequencies of widely varying strengths; they were not transients but repeatable and characteristic constituents of i the discharge current. It was also striking to observe the sensibly instantaneous and reversible diminution of the amplitudes of these component frequencies, on irradiating the discharge tube, as shown by a typical pair of oscillograms reproduced herewith.