Estimates of the Nuclear Time Delay in Dissipative U + U and U + Cm Collisions Derived from the Shape of Positron and δ-Ray Spectra

摘要: Positron and delta-ray spectra have been measured in coincidence with quasielastic scattered particles fission fragments from the bombardment of Pd, U, Cm targets U beams energies between 5.9 8.4 MeV/u. For collisions leading to a reaction, atomic positron fall off more steeply at high than expected calculations based on pure Rutherford trajectories. A quantitative analysis this effect is accord nuclear contact time about 10/sup -21/ s.