Odd-even absorption in 3He + 3He scattering and level structure of 6Be

Differential cross sections for ³He + ³He elastic scattering are calculated at c.m. energies from 2.95 to 37.44 MeV using the one-channel resonating-group method. A phenomenological imaginary potential, whose strength depends on whether the relative orbital angular momentum is even or odd, is included in order to account approximately for open reaction channels. The introduction of such an odd-even feature leads to a significantly improved agreement with experiment, especially at the larger scattering angles. In addition, an analysis of the calculated resonant phase shifts confirms recent experimental observations of highly excited levels in ⁶Be.