Fission studies in inverse kinematics with the R³B setup

¹ IGFAE, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain
² Technische Universität Darmstadt, Fachbereich Physik, Institut für Kernphysik, 64289 Darmstadt, Germany
³ IPN Orsay, 15 rue Georges Clemenceau, 91406, Orsay, France
⁴ CEA Saclay, IRFU/DPhN, Centre de Saclay, 91191, Gif-sur-Yvette, France
⁵ CINTECX, Universidade de Vigo, DSN, 36310 Vigo, Spain
⁶ CEA, DAM, DIF, F-91297 Arpajon, France
⁷ GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, D-64291 Darmstadt, Germany
⁸ Instituto de Estructura de la Materia, CSIC, E-28006 Madrid, Spain
⁹ Department of Physics, Lund University, P.O. box 118, 221 00 Lund, Sweden
¹⁰ INFN Laboratori Nazionali del Sud, Via Santa Sofia 62, 95123, Catania, Italy
¹¹ LIP and Faculty os Sciences, University of Lisbon, 1000-149 Lisbon, Portugal
¹² RBI Zagreb, Bijenicka cesta 54, HR10000, Zagreb, Croatia
¹³ Technische Universität München, James-Franck-Str 1, 85748, Garching, Germany
¹⁴ Institutionen för Fysik, Chalmers Tekniska Högskola, 412 96 Göteborg, Sweden
¹⁵ Institut für Kern-und Teilchenphysik, Technische Universität Dresden, 01069 Dresden, Germany
¹⁶ University of Guelph, 50 Stone Road E, N1G 2W1, Guelph, ON, Canada
¹⁷ Institut für Kernphysik der Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
¹⁸ School of Physics, Engineering and Technology, University of York, YO10 5DD York, UK
¹⁹ Institute for Basic Science, Center for Exotic Nuclear Studies, 34126, Daejeon, Republic of Korea
²⁰ Jozef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia

^* Corresponding author: antia.grana.gonzalez@usc.es

Published online: 8 December 2023

Abstract

Nuclear fission is a complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. For this reason, to this day it still lacks a satisfactory and complete microscopic description. In addition to the importance of describing fission itself, studies of the r-process in astrophysics depend on fission observables to constrain the theoretical models that explain the isotopic abundances in the Universe. To improve on the existing data, fission reactions of heavy nuclei in inverse kinematics are produced in quasi-free (p,2p) scattering reactions, which induce fission through particle-hole excitations that can range from few to tens of MeV. In order to study the evolution of the fission yields with temperature, the excitation energy of the fissioning system must be reconstructed, which is possible by measuring the four-momenta of the two outgoing protons. Performing this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and some of the results obtained for the charge distributions are presented in this work.