In high-current coaxial diodes with rod anode (rod pinch diodes), the curre
nt of the magnetic self-insulation in the gap is approximately two times gr
eater than the critical magnetic insulation current (J(S) approximate to 2J
(C)). Based on this fact, a model is proposed according to which a quasista
tionary electron pinch state in such diodes is explained by a change in the
gap magnetic insulation conditions caused by the pinch formation. This cir
cumstance can be used to evaluate the pinch lifetime Deltat. The Deltat val
ues calculated using the oscillograms measured on the Gamble I accelerator
agree satisfactorily with the values experimentally determined in a coaxial
rod pinch diode. (C) 2001 MAIK "Nauka/ Interperiodica".