Excitation-energy influence at the scission configuration

¹ USC, E-15784 Santiago de Compostela, Spain
² GANIL, CEA/DMS-CNRS/IN2P3, BP. 55027, 14076 Caen Cedex 05, France
³ IPN Orsay, Université de Paris-Sud, CNRS/IN2P3, 91406 Orsay Cedex, France
⁴ CIMA, UVigo, 36310 Vigo, Spain
⁵ LPC Caen, Université de Caen Basse-Normandie-ENSICAEN-CNRS/IN2P3, 14050 Caen Cedex, France
⁶ CEA Saclay, DMS/IRFU/SPhN, 91191 Gif-sur-Yvette Cedex, France
⁷ Chalmes University of Technology, 41296 Göteborg, Sweden

^a e-mail: diego.ramos@usc.es
^b Present Address: CEA DAM DIF, 91297 Arpajon, France
^c Present Address: EC-JRC-IRMM, Retieseweg 111, 2440 Geel, Belgium

Published online: 13 September 2017

Abstract

Transfer- and fusion-induced fission in inverse kinematics was proven to be a powerful tool to investigate nuclear fission, widening the information of the fission fragments and the access to unstable fissioning systems with respect to other experimental approaches. An experimental campaign for fission investigation has being carried out at GANIL with this technique since 2008. In these experiments, a beam of ²³⁸U, accelerated to 6.1 MeV/u, impinges on a ¹²C target. Fissioning systems from U to Cf are populated through transfer and fusion reactions, with excitation energies that range from few MeV up to 46 MeV. The use of inverse kinematics, the SPIDER telescope, and the VAMOS spectrometer permitted the characterization of the fissioning system in terms of mass, nuclear charge, and excitation energy, and the isotopic identification of the full fragment distribution. The neutron excess, the total neutron multiplicity, and the even-odd staggering in the nuclear charge of fission fragments are presented as a function of the excitation energy of the fissioning system. Structure effects are observed at Z∼50 and Z∼55, where their impact evolves with the excitation energy.