\u3000This paper is about the measurements of neutron energy spectra of 345 MeV\/u*<\/sup> 238<\/sup>U (uranium-238) incident on a copper target conducted at RIKEN. To carry out experiments with unstable nuclei, high-intensity beam is required such as RIKEN Nishina Center. Data on the secondary neutron yields (TTY: Thick Target Yield) produced by the reactions between thick targets and 238<\/sup>U beam with several hundred mega-electron volts per nucleon are crucial. However, the prediction accuracy of the Monte Carlo transport code has to be verified because the nuclear reaction model, which can be applied to fragment nuclei production, is not fully validated due to the lack of comprehensive measurements with 238<\/sup>U beam at several hundred mega-electron volts per nucleon. The measured data by Dr. Sugihara are not only important for engineering such as shielding design, but also make significant contribution to basic science such as improving the accuracy of nuclear reaction models.<\/p>\n\n\n\n *MeV is a unit of energy. 1 eV corresponds to the energy gained by a single particle with quantum of electricity due to a potential of 1 V (volt), and MeV is one million times that. The unified atomic mass unit u is one-twelfth the mass of a 12<\/sup>C, an isotope of carbon, and is approximately equal to the mass of a nucleon (proton or neutron).<\/p>\n\n\n\n
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