Monte Carlo Analysis of the Accelerator-Driven System at Kyoto University Research Reactor Institute

An accelerator-driven system consists of a subcritical reactor and a controllable external neutron source. The reactor in an accelerator-driven system can sustain fission reactions in a subcritical state using an external neutron source, which is an intrinsic safety feature of the system. The system can provide efficient transmutations of nuclear wastes such as minor actinides and long-lived fission products and generate electricity. Recently at Kyoto University Research Reactor Institute (KURRI; Kyoto, Japan), a series of reactor physics experiments was conducted with the Kyoto University Critical Assembly and a Cockcroft-Walton type accelerator, which generates the external neutron source by deuterium-tritium reactions. In this paper, neutronic analyses of a series of experiments have been re-estimated by using the latest Monte Carlo code and nuclear data libraries. This feasibility study is presented through the comparison of Monte Carlo simulation results with measurements.clos

Introduction to Nuclear Reactor Experiments

This open access book is a pedagogical text on nuclear reactor experiments, covering almost all the experiments that can be carried out at the University Training Reactor, Kindai University (UTR-KINKI) with respect to reactor physics and radiation detection, and additionally including academic materials of test and research reactors, nuclear instrumentation, nuclear laws and regulations, in this main body. The book is an excellent primer for students who are interested in reactor physics, radiation detection, nuclear laws and regulations at universities, and the best textbook for students who have started to study the nuclear energy related fields to understand the basic theories and principles of the experiments in the fields of reactor physics and radiation detection. UTR-KINKI has been used for educational reactor experiments and basic research in a wide range of fields related to the use of radiation (neutrons, gamma-ray, beta-ray, alpha-ray, and X-ray), including reactor physics, radiation detection, radiation health physics, activation analysis, radiation biology, medical applications and archaeology. Also, UTR-KINKI has been actively engaged in nuclear education with its long history of operation, and has gained extensive experience in educational activities for undergraduate and graduate students, elementary, junior high and high school teachers, junior high and high school students, and general audiences

Introduction to Nuclear Reactor Experiments

This open access book is a pedagogical text on nuclear reactor experiments, covering almost all the experiments that can be carried out at the University Training Reactor, Kindai University (UTR-KINKI) with respect to reactor physics and radiation detection, and additionally including academic materials of test and research reactors, nuclear instrumentation, nuclear laws and regulations, in this main body. The book is an excellent primer for students who are interested in reactor physics, radiation detection, nuclear laws and regulations at universities, and the best textbook for students who have started to study the nuclear energy related fields to understand the basic theories and principles of the experiments in the fields of reactor physics and radiation detection. UTR-KINKI has been used for educational reactor experiments and basic research in a wide range of fields related to the use of radiation (neutrons, gamma-ray, beta-ray, alpha-ray, and X-ray), including reactor physics, radiation detection, radiation health physics, activation analysis, radiation biology, medical applications and archaeology. Also, UTR-KINKI has been actively engaged in nuclear education with its long history of operation, and has gained extensive experience in educational activities for undergraduate and graduate students, elementary, junior high and high school teachers, junior high and high school students, and general audiences

Benchmarks of subcriticality in accelerator-driven system at Kyoto University Critical Assembly

Basic research on the accelerator-driven system is conducted by combining U-235-fueled and Th-232-loaded cores in the Kyoto University Critical Assembly with the pulsed neutron generator (14 MeV neutrons) and the proton beam accelerator (100 MeV protons with a heavy metal target). The results of experimental subcriticality are presented with a wide range of subcriticality level between near critical and 10,000 pcm, as obtained by the pulsed neutron source method, the Feynman-alpha method, and the neutron source multiplication method

Neutron Generation Time in Highly-Enriched Uranium Core at Kyoto University Critical Assembly

At the Kyoto University Critical Assembly experiments on kinetics parameters are carried out at near-critical configurations, supercritical and subcritical states, in the thermal neutron spectrum made with a highly enriched uranium fuel. The main calculated kinetics parameters, the effective delayed neutron fraction (βeff) and the neutron generation time (Ʌ), are used effectively for the estimation of experimental parameters, and the accuracy of experiments on prompt neutron decay constant (α) and subcriticality (ρ$) in dollar units is attained by the numerical results of βeff and Ʌ. Furthermore, the value of βeff/Ʌ is experimentally deduced with the use of the experimental results of α and ρ$, ranging between 250 and −80 pcm. Thus, the experimentally deduced values of βeff/Ʌ that reveal good accuracy through a comparison with those by the MCNP6.1 calculations with JENDL-4.0 are then taken as an index of Ʌ by introducing an acceptable assumption of βeff at near-critical configurations. From the results of experimental and numerical analyses, the experimental value of βeff/Ʌ is important for the validation of Ʌ since kinetics parameters are successfully obtained from the clean cores of near-critical configurations in the thermal neutron spectrum

Research and development for accuracy improvement of neutron nuclear data on minor actinides

To improve accuracy of neutron nuclear data on minor actinides, a Japanese nuclear data project entitled “Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC)” has been implemented. Several independent measurement techniques were developed for improving measurement precision at J-PARC/MLF/ANNRI and KURRI/LINAC facilities. Effectiveness of combining the independent techniques has been demonstrated for identifying bias effects and improving accuracy, especially in characterization of samples used for nuclear data measurements. Capture cross sections and/or total cross sections have been measured for Am-241, Am-243, Np-237, Tc-99, Gd-155, and Gd-157. Systematic nuclear data evaluation has also been performed by taking into account the identified bias effect. Highlights of the AIMAC project are outlined

Experimental Benchmarks of Neutronics on Solid Pb-Bi in Accelerator-Driven System with 100 MeV Protons at Kyoto University Critical Assembly

この実験ベンチマーク問題は、国際原子力機関(IAEA)において2016 年から2018年にかけて行われた国際共同研究プロジェクトT33002「加速器駆動システム(ADS)とADS における低濃縮ウラニウムの利用」の一部として採択された「京都大学臨界集合体実験装置における100 MeV 陽子を用いた加速器駆動システムの固体Pb-Bi の中性子特性に関する実験ベンチマーク」である。この実験ベンチマーク問題は、KUCA のA 架台において行われたFFAG 加速器から得られる核破砕中性子を用いた実験を通して、ADS におけるPb-Bi の基礎研究の発展に貢献することを目的としている。These experimental benchmarks were contributed to the Coordinated Research Project (CRP) T33002 in the International Atomic Energy Agency (IAEA), as entitled “Accelerator Driven Systems (ADS) and Use of Low-Enriched Uranium in ADS, ” from 2016 to 2018. The main objective of these benchmarks is to contribute to research and development of Pb-Bi neutronics in ADS through the experimental data with the use of spallation neutrons generated by 100 MeV protons and Pb-Bi target carried out at the Kyoto University Critical Assembly (KUCA) A-core

第14回加速器駆動システムおよび核変換技術に関するアジアネットワークワークショップ報告書

編集: 卞 哲浩Edited by Cheol Ho PyeonActivities in JAEA induced 1st Technical Meeting (Sep., 2015) for ADS-NTT 2015 Dr. Toshinobu Sasa (JAEA, Japan) [1]Status of SNF, Gen-IV & ADS in Korea Prof. Seung-Woo Hong (Sungkyunkwan Univ., Korea) [24]Current Status of Subcritical Reactor Technology for ADS in China Prof. Yunqing Bai (INEST, CAS, China) [51]Current Status on ADS Experiments at KUCA Prof. Cheolho Pyeon (KURRI, Japan) [62