Direct Observation of Coulomb Fission ofU238withW184Projectiles

The excitation function for fission of ${}_{}{}^{238}{}_{}{}^{}\mathrm{U}$ following inelastic scattering of ${}_{}{}^{184}{}_{}{}^{}\mathrm{W}$ ions was measured by identification of internal conversion transitions in the backscattered ions. The observed fission cross section at the lowest energies is consistent with a dominant contribution from the Coulomb interaction, whereas at the highest energies one is unable to establish a predicted interference minimum between Coulomb and nuclear forces.