In the realm of nuclear physics and energy research, a team of scientists from the Japan Atomic Energy Agency has been delving into the nuances of nuclear reactions. The researchers, led by Yamato Fujii and including Naohiko Otuka, Kenta Sugihara, Masayuki Aikawa, Hiromitsu Haba, and Isao Murata, have recently published their findings in the journal “Nuclear Instruments and Methods in Physics Research Section A.”
The team’s study focuses on the influence of secondary neutrons on measurements of alpha-particle induced reaction cross sections below the Coulomb barrier. Specifically, they examined the reaction involving natural platinum ($^\mathrm{nat}$Pt) and alpha particles, which results in the production of a radioactive isotope of platinum, $^\mathrm{195m}$Pt.
To understand the role of secondary neutrons, the researchers used the particle transport simulation code PHITS to characterize the neutron field. They then estimated the yields of $^\mathrm{195m}$Pt from natural platinum targets bombarded with neutrons, using the characterized neutron spectra and cross-section data from the JENDL-5/A library. Their findings revealed that the unexpectedly high cross sections measured for the $^\mathrm{nat}$Pt($α$,x)$^\mathrm{195m}$Pt reaction below the Coulomb barrier could be largely attributed to the $^\mathrm{nat}$Pt(n,x)$^\mathrm{195m}$Pt reaction induced by secondary neutrons.
This discovery underscores the importance of considering the secondary neutron effect in low-energy charged-particle activation cross-section measurements. While the study also investigated the influence of secondary light charged particles, it found their impact to be negligible.
For the energy industry, this research highlights the need for precise and accurate measurements in nuclear reactions, particularly those involving alpha particles. Understanding the role of secondary neutrons can help improve the design and safety of nuclear reactors, as well as enhance the accuracy of nuclear waste management and disposal strategies. Additionally, this knowledge can contribute to the development of advanced nuclear fuels and the optimization of nuclear fusion reactions.
This article is based on research available at arXiv.