Electrofission in the quasifree and delta regions

The coincident electrofission (e,e'f) cross sections of ^233,238U were measured in the excitation range 150-550 MeV. The probability of fission was found to be near unity in the delta resonance region (250-550 MeV), but less than unity in the quasifree scattering region (150-250 MeV). The data are analyzed with a model based on the quasifree and delta reaction mechanisms. An excitation energy of 25 MeV is found for the residual nucleus in the quasifree region and over 40 MeV in the delta region.