Angular momentum transfer in 12C-, 20Ne- and 40Ar-induced fission

Energy dependence of the promptγ-ray emission from the(d,p)-induced fission ofU*Rose1, Zeiser2, Wilson3 et al. 2017Phys. Rev. C121110View full textAdd to dashboardCite

“…The targets were cleaned from decay products and other chemical impurities with an anion-exchange resin column procedure [24], and then electroplated on a backing made of 9 Be. For these particular experiments, the SiRi detectors were mounted in backward direction, and the NIFF detectors in forward direction, relative to the beam direction (see Fig.…”

“…Prompt fission γ-ray spectral (PFGS) data, measured as a function of excitation energy of the compound nucleus may provide important information to benchmark different models, allowing eventually arrival at a consistent description of prompt fission neutron and γ-ray emission. Furthermore, PFGs are certainly among the most sensitive observables for studying angular momentum generation in fission [8,9].…”

Angular momentum bearing modes and nuclear structure effects in12C-induced fission

“…While this simple picture of rigid rotation predicts an increase in the total fragment spin with increasing mass asymmetry, several studies have shown that M r actually peaks at symmetry [1,2,5]. In other measurements, especially those involving asymmetric entrance channels, M r has been found to be nearly independent of the mass split [3,4]. Moreover, the magnitude of M r is often considerably larger than one would expect from the entrance channel /-distribution [1,[3][4][5][6], implying a spin enhancement effect.…”

“…In other measurements, especially those involving asymmetric entrance channels, M r has been found to be nearly independent of the mass split [3,4]. Moreover, the magnitude of M r is often considerably larger than one would expect from the entrance channel /-distribution [1,[3][4][5][6], implying a spin enhancement effect. It has been suggested that the deviations from the rigid rotation pattern could arise from the excitation of the tilting mode [1], which, it should be recalled, forms the basis for the theory of fission fragment angular distributions.…”

“…Other degrees of freedom, such as bending, wriggling and twisting, may also be excited in the fission process. Model calculations which assume the thermal excitation of these modes have met with some success in describing the variation of the total fragment spin with mass asymmetry as well as the magnitude of the fragment spin [3][4][5].…”