Influence of the ground state spin of target nuclei on the anomalous behavior of fission fragment anisotropies

The angular distributions of fission fragments have been measured over a range of near- and sub-barrier energies for reactions involving ¹²C projectiles on 235,236,238U targets. For the reactions involving the zero spin targets, the discrepancies between the experimental fission anisotropies and the transition state model increase dramatically as the beam energy decreases through the region of the fusion barriers. However, the ¹²C+(I=7/2)²³⁵U fission anisotropies exhibit a much less dramatic departure from the transition state model.