# Plasma and Fusion Research

## Volume 16, 1405074 (2021)

# Regular Articles

- Chubu University, 1200 Matsumoto-cho, Kasugai-city, Aichi 487-8501, Japan

### Abstract

The objective of this article is to provide a database for the transmutation of LLFP (long-lived fission products) using neutrons of muon-catalyzed nuclear fusion (MCF). As examples of LLFP with a natural half-life of more than 10^{5} years, four nuclides, ^{107}Pd, ^{135}Cs, ^{79}Se and ^{93}Zr, are chosen. Taking simplified geometrical models of the neutron source and blanket, which appear in the conceptual design of in-flight MCF, the nuclide production yield was calculated by a three-dimensional Monte Carlo calculation based on nuclear data. The number of neutrons and flux, which are necessary to convert half of the initial LLFP amount into a stable nucleus, are obtained. We also investigated the method of controlling two competing reactions of the nuclear fractions by fast neutrons, called the (n, 2n) reaction, and the neutron captures of the thermal neutrons. Theoretical simulation studies have revealed the quantity of LLFP that is detoxified by transmutation under the condition that the fusion neutrons are continuously irradiated to LLFP for approximately 10 years with a flux of 10^{19} m^{−2} s^{−1}.

### Keywords

muon-catalyzed nuclear fusion, LLFP, neutron, transmutation by neutron

### Full Text

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