Measurement of Independent Fission Yields in Direct and Inverse Kinematics

Fission product yields are an important observable for fundamental and applied nuclear physics. Recent advances in radioactive beam technology have allowed measurements of fragments from fission induced by transfer reactions and virtual photons in inverse kinematics with superb charge and mass resolution. We are beginning a program to study the independent fission yields before beta decay in both direct and inverse kinematics to benchmark these new techniques. We will discuss an experiment to measure photofission of ²³⁸U in direct kinematics using a position-sensitive Frisch-grid ionization chamber. This detector allows determination of the distributions of the independent fission yield mass, total kinetic energy, and azimuthal angle as well as correlations between these values. These distributions will be compared to measurements of fission induced by transfer reactions and virtual photons in inverse kinematics. Preliminary data from recent measurements in direct kinematics using a Frisch-grid ionization chamber will be presented.