Dipole strength in ⁸⁰Se below the neutron-separation energy for the nuclear transmutation of ⁷⁹Se

¹ Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
² JEIN institute for fundamental science, NPO Einstein, Kyoto, 606-8317, Japan
³ Graduate School of Medicine, Hokkaido University, 060-8638 Sapporo, Japan
⁴ Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
⁵ Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556, USA
⁶ RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
⁷ Technische Universität Dresden, 01062 Dresden, Germany

^a e-mail: makinaga@nucl.sci.hokudai.ac.jp

Published online: 13 September 2017

Abstract

The γ-ray strength function (γSF) in ⁸⁰Se is an important parameter to estimate the neutron-capture cross section of ⁷⁹Se which is one of the long-lived fission products (LLFPs). Until now, the γSF method was applied for ⁸⁰Se only above the neutron-separation energy (S_n) and the evaluated ⁷⁹Se(n,γ) cross section has an instability caused by the GSF below S_n. We studied the dipole-strength distribution of ⁸⁰Se in a photon-scattering experiment using bremsstrahlung produced by an electron beam of an energy of 11.5 MeV at the linear accelerator ELBE at HZDR. The present photoabsorption cross section of ⁸⁰Se was combined with results of (γ,n) experiments and are compared with predictions usinmg the TALYS code. We also estimated the ⁷⁹Se(n,γ) cross sections and compare them with TALYS predictionms and earlier work by other groups.