LABORATORI NAZIONALI DI LEGNARO
The synthesis of super-heavy elements (SHEs) continues to be one of premiere frontiers of nuclear physics. There have been several reports on the production of super-heavy nuclei using different target-projectile combinations using cold fusion reactions by the observation of evaporation residues. However, the fission path in these reactions has not been investigated in full detail. The fission characteristics of the super-heavy nuclei can be studied through binary fragmentation reactions in the exit channel of suitably selected heavy ion reactions, provided that the binary fragmentations resulting from the fission of compound nucleus can be separated from those resulting from non-compound processes. Further recent experimental data on cold fusion reactions leading to the formation of super-heavy nuclei with Z<113 shows a strong dependence on coulomb parameter. In order to further investigate the dynamics of binary fragmentation and fusion-fission of super-heavy systems, we carried out detailed investigation of fragment mass vs total kinetic energy distribution and neutron emission in the 294 MeV 50Ti + 208Pb reaction, leading to the formation of the super-heavy nucleus 258Rf, for which residues have been experimentally observed. Two Time of Flight arms based on position sensitive MCP detectors were used to catch the two complementary fragments providing a full kinematics reconstruction of the event. The emitted neutrons were detected by using an array of BC501 liquid scintillators. The neutron energy was determined by measuring the time-of-flight (TOF) with respect to the MCP start signal. A custom digital acquisition system was used. Preliminary results will be presented and discussed.

DATA: 09-07-2014