The radiation induced conductivity (RIC) of polyethylene terephthalate (Mylar) produced by the electron beam from a pinched electron beam diode has been measured experimentally. Data were obtained for 4ndash;10 ns duration electron beam pulses at radiation dose rates up to 4times;1016rad/s (100 kA/cm2current density). The conductivity is roughly proportional to radiation dose rate up to about 100 Mrad and at higher doses scales approximately with radiation dose to the (3)/(2) power. The experimental data are compared to the predictions of a model of RIC using dispersive electronic transport and bimolecular recombination. The parameters used in the model were obtained from published low dose (100 rad) timehyphen;resolved photoconductivity measurements on Mylar. The data agreed well with the calculations before the onset of significant sample heating (10 Mrad). The highest reported RIC results are compared to the expected results for a weakly ionized plasma experiencing electron neutral collisions. In this case the experimental conductivity is significantly higher than the calculated value.
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