Electrical breakdown induced by long lived metastable states in nitrogen

The total time delay of electrical breakdown (t d ) and its dependence on current, flowing through a discharge in pure nitrogen after breakdown, has been investigated, using three geometrically identical diodes filled at pressures of 1.33, 4.00 and 13.33 mbar. It was shown that curve minima depend on the nitrogen pressure in the diodes and seem to be related to the maxima in concentrations of metastable states inducing secondary electron emission from the cathode.