Fission-Fragment Scattering

The scattering of fission fragments of ${\mathrm{Cf}}^{252}$ from a thick, flat sheet of platinum has been studied with a coincidence arrangement using silicon surface-barrier detectors. Data are presented showing the percentage of fragments scattered out of the platinum as a function of angle of entry of the fragments. At low (grazing) angles of entry 50% or more of the fragments entering the platinum are scattered out. The scattering decreases rapidly with increasing entrance angle and is less than 1% at 30°.