Fission dynamics with systems of intermediate fissility

Abstract

A 4 pi light charged particle spectrometer, called 8 pi LP, is in operation at the Laboratori Nazionali di Legnaro, Italy, for studying reaction mechanisms in low-energy heavy-ion reactions. Besides about 300 telescopes to detect light charged particles, the spectrometer is also equipped with an anular PPAC system to detect evaporation residues and a two-arm time-of-flight spectrometer to detect fission fragments. The spectrometer has been used in several fission dynamics studies using as a probe light charged particles in the fission and evaporation residues (ER) channels. This paper proposes a journey within some open questions about the fission dynamics and a review of the main results concerning nuclear dissipation and fission time-scale obtained from several of these studies. In particular, the advantages of using systems of intermediate fissility will be discussed

Evaporation channel as a tool to study fission dynamics

“…Phenomenological studies based on the SM predictions were carried out with the aim to estimate the fission delay time, and, in some cases, extract the strength of nuclear viscosity. The estimates given by different authors predict a quite wide range of dissipation strengths and different dependencies on temperature and deformation (see reviews [9][10][11] and references therein). However, this kind of approach is founded on the reliability of the SM to reproduce the observables in the evaporation residue (ER) channel, and this has not yet been fully explored.…”