Formation of a preionized bulk discharge in nitrogen using radioisotopes

Formation of a homogeneous preionized pulsed discharge is studied. The calculated electron density and the measured density during discharge development n(t) are compared, and it is shown that for initial electron densities n0> or =108 cm-3 active bulk ionization of the gas in a uniform electric field almost equal to the external field is responsible for discharge ignition, i.e., an electric field is applied to a weakly ionized plasma. The current was observed to be delayed relative to the voltage pulse, and the delay is attributed to the fact that ionization does not occur instantaneously