Employing FREYA for fission product yield evaluations

¹ Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
² Physics Department, University of California at Davis, Davis, CA 95616, USA
³ Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
⁴ Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA

^* e-mail: Vogt2@LLNL.gov
^** e-mail: JRandrup@LBL.gov

Published online: 28 September 2020

Abstract

The fast event-by-event fission code FREYA (Fission Reaction Event Yield Algorithm) generates large samples of complete fission events while employing only a few physics-based parameters. Not only is FREYA fast, it is also flexible, able to employ a variety of input formats to test the implications of various fission yield evaluations on neutron and photon observables. We describe how FREYA was applied to the neutron-rich nuclei needed for r-process nucleosynthesis calculations as an example of this flexibility. Finally, we discuss how we plan to make use of this flexibility to extend FREYA to calculations of cumulative fission product yields to aid evaluations of these yields in the future.