{"id":4739,"date":"2026-06-02T07:56:07","date_gmt":"2026-06-01T22:56:07","guid":{"rendered":"https:\/\/adm.rri.kyoto-u.ac.jp\/pub\/?p=4739"},"modified":"2026-06-02T07:56:07","modified_gmt":"2026-06-01T22:56:07","slug":"kurri-tr-433","status":"publish","type":"post","link":"https:\/\/adm.rri.kyoto-u.ac.jp\/pub\/kurri-tr-433\/","title":{"rendered":"KURRI-TR-433"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

Joint Reactor Laboratory Course for Students in KUCA<\/p>\n\n\n\n

April 2004
Tsuyoshi Misawa, Hironobu Unesaki, Chihiro Ichihara, Cheol Ho Pyeon and Seiji Shiroya<\/p>\n\n\n\n

Contents<\/strong><\/p>\n\n\n\n

Introduction to Kyoto University Critical Assembly (KUCA)<\/p>\n\n\n\n

1. General Description of the KUCA Facility  \/p.1<\/p>\n\n\n\n

1-1 The KUCA Facility   \/p.1<\/p>\n\n\n\n

1-2 Solid-Moderated Cores (A & B Cores)  \/p.2<\/p>\n\n\n\n

1-3 Light-Water Moderated Core (C core)  \/p.3<\/p>\n\n\n\n

1-4 Pulsed Neutron Source  \/p.4<\/p>\n\n\n\n

1-5 Control Room  \/p.5<\/p>\n\n\n\n

2. Detail of the Light-Water Moderated Core (C core)   \/p.6<\/p>\n\n\n\n

2-1 Overall Structures  \/p.6<\/p>\n\n\n\n

2-2 Core Tank and Grid Plate  \/p.7<\/p>\n\n\n\n

2-3 Fuel Plates and Fuel Frames  \/p.7<\/p>\n\n\n\n

2-4 Core Configurations  \/p.10<\/p>\n\n\n\n

Chapter 1 Approach to Criticality<\/p>\n\n\n\n

1-1 Chain Reaction of Nuclear Fission, Neutron Multiplication and Approach to Criticality  \/p.12<\/p>\n\n\n\n

1-1-1 Fission Chain Reaction: Neutron Multiplication in a Subcritical Media  \/p.12<\/p>\n\n\n\n

1-1-2 Neutron Multiplication in a Subcritical Media  \/p. 14<\/p>\n\n\n\n

1-1-3 Inverse Count Rate and Criticality Approach  \/p.15<\/p>\n\n\n\n

1-2 Experiments  \/p.18<\/p>\n\n\n\n

1-2-1 Neutron Detectors  \/p. 18<\/p>\n\n\n\n

1-2-2 Actual Procedures of the Experiment  \/p.18<\/p>\n\n\n\n

1-2-3 Additional Experiment: Determination of Infinite Reflector Thickness  \/p.22<\/p>\n\n\n\n

1-3 Report   \/p. 24<\/p>\n\n\n\n

1-4Preparatory Report  \/p.25<\/p>\n\n\n\n

1-4-1 Numerical Simulation of the Critical Approach Experiment  \/p.25<\/p>\n\n\n\n

1-4-2 2-Group Diffusion Calculation of a Reflected Reactor   \/p. 29<\/p>\n\n\n\n

Appendix 1   \/p.34<\/p>\n\n\n\n

1A. Analytical Solution of the 2-Group Diffusion Equation  \/p.34<\/p>\n\n\n\n

1B. Solution for Core Region  \/p.36<\/p>\n\n\n\n

1C. Reflector Region  \/p.39<\/p>\n\n\n\n

1D. De termination of Critical Core Size  \/p.41<\/p>\n\n\n\n

1E. Neutron Flux Distribution  \/p.44<\/p>\n\n\n\n

Chapter 2 Control Rod Calibration<\/p>\n\n\n\n

2-1 Purpose of Control Rod Calibration  \/p.45<\/p>\n\n\n\n

2-2 Principles  \/p.47<\/p>\n\n\n\n

2-2-1 Reactor Kinetic Equation  \/p.47<\/p>\n\n\n\n

2-2-2 Positive Period Method  \/p.48<\/p>\n\n\n\n

2-2-3 Control Rod Drop Metho  \/p.50<\/p>\n\n\n\n

2-2-4 Compensation Method  \/p.53<\/p>\n\n\n\n

2-3 Experiments  \/p.54<\/p>\n\n\n\n

2-3-1 Core Configurations   \/p.54<\/p>\n\n\n\n

2-3-2 Period Method Experiment  \/p.56<\/p>\n\n\n\n

2-3-3 Rod Drop Method Experiment  \/p.56<\/p>\n\n\n\n

2-4Discussions  \/p.57<\/p>\n\n\n\n

2-5 Preparatory Report  \/p.58<\/p>\n\n\n\n

Appendix 2 \u2022 \u2022 \u2022 \u30fb5 9<\/p>\n\n\n\n

2A. Neutron Lifetime  \/p.59<\/p>\n\n\n\n

2B. Delayed Neutron Data and Basic Parameters of KUCA  \/p.60<\/p>\n\n\n\n

2C. First Order Perturbation Theory  \/p.61<\/p>\n\n\n\n

2D. Control Rod Calibr~tion Curve  \/p.64<\/p>\n\n\n\n

Chapter 3 Measurement of Reaction Rate Dis\u51fabution<\/p>\n\n\n\n

3-1 Purpose  \/p.65<\/p>\n\n\n\n

3-2 Principle of Measurement by Activation Detector  \/p.67<\/p>\n\n\n\n

3-2-1 Features of a Neutron Activation Detector   \/p.67<\/p>\n\n\n\n

3-2-2 Principle of Measurement of Neutron Flux by Using an Activation Detector  \/p.68<\/p>\n\n\n\n

3-2-3 Principle of Measuring Radioactivity by Using Gold (Au) Activation Foil  \/p.71<\/p>\n\n\n\n

3-2-4 Determination of Detection Coefficient  \/p.73<\/p>\n\n\n\n

3-3 Determination of the Activation Reaction Rate by Thermal Neutron Flux  \/p.75<\/p>\n\n\n\n

3-3-1 Neutron Spectrums in the Reactor Core  \/p.75<\/p>\n\n\n\n

3-3-2 Activation Reaction Rate by Thermal Neutrons  \/p.77<\/p>\n\n\n\n

3-4 Experiments  \/p.87<\/p>\n\n\n\n

3-4-1 Core Configuration  \/p.87<\/p>\n\n\n\n

3-4-2 Equipment and Irradiation of Gold Wires and Foils with the Core  \/p.87<\/p>\n\n\n\n

3-4-3 Measurement of the Radiation of the Gold Wires and Foils  \/p.89<\/p>\n\n\n\n

3-5 Preparation of Experimental Data and Report  \/p.94<\/p>\n\n\n\n

3-6 Preparatory Report  \/p.97<\/p>\n\n\n\n

References  \/p.100<\/p>\n\n\n\n

Appendix 3  \/p.101<\/p>\n\n\n\n

3A. Absolute Measurement of the Activation Reaction Rate by the 4\u03c0\u03b2-\u03b3 Coincidence Method  \/p.1 01<\/p>\n\n\n\n

3A-1 Principles of the 41rP-rCoincidence Method  \/p.101<\/p>\n\n\n\n

3A-2 Absolute Measurement by the  4\u03c0\u03b2-\u03b3 Coincidence Method  \/p.103<\/p>\n\n\n\n

3B. Outline and Instruction of Measurement Equipment by an HPGe Detector  \u30fb 1 05<\/p>\n\n\n\n

Chapter 4 Neutron Correlation Experiment Feynman-\u03b1 Method<\/p>\n\n\n\n

4-1 Purpose  \/p.107<\/p>\n\n\n\n

4-2 Variance-to-Mean Ratio in a Multiplication System   \/p.108<\/p>\n\n\n\n

4-2-1 Decay Constant \u03b1  \/p.109<\/p>\n\n\n\n

4-2-2 \u03b3Value Expressed by Reactivity  \/p.110<\/p>\n\n\n\n

4-2-3 Amount of \u03b3 value  \/p.111<\/p>\n\n\n\n

4-2-4 Asymptotic Behavior of \u03b3  \/p.111                      <\/p>\n\n\n\n

4-2-5 \u03b3Value in a Critical System by Delayed Neutrons  \/p.112<\/p>\n\n\n\n

4-2-6 Relationship between Power and the Value  \/p.113<\/p>\n\n\n\n

4-3 Experiments  \/p.114<\/p>\n\n\n\n

4-3-1 Equipment Needed  \/p.114<\/p>\n\n\n\n

4-3-2 Experimental Methods  \/p.116<\/p>\n\n\n\n

4-3-3 Data Processing  \/p.118<\/p>\n\n\n\n

4-4 Reports and Discussions  \/p.119<\/p>\n\n\n\n

4-4-1 Reports  \/p.119<\/p>\n\n\n\n

4-4-2 Discussions  \/p.120<\/p>\n\n\n\n

References  \/p.121<\/p>\n\n\n\n

Appendix 4  \/p.122<\/p>\n\n\n\n

Derivation of Feynman-a Method Equations  \/p.122<\/p>\n\n\n\n

4A-1 Steady State  \/p.126<\/p>\n\n\n\n

4A-2 Consideration of Delayed Neutrons  \/p.127<\/p>\n\n\n\n

4A-3 Initial Correlation Correction, Spatial Dependence and Fission Counter  \/p.128<\/p>\n\n\n\n

Chapter 5 Measurement of Reactivity by the Pulsed Neutron Method<\/p>\n\n\n\n

5-1 Purpose   \/p.129<\/p>\n\n\n\n

5-2 Principle of the Experiment  \/p.130<\/p>\n\n\n\n

5-3 Experimental Equipment   \/p.137<\/p>\n\n\n\n

5-4 Experimental Methods   \/p.138<\/p>\n\n\n\n

5-5 Data Processing   \/p.139<\/p>\n\n\n\n

5-6 Reports and Discussion  \/p.140<\/p>\n\n\n\n

References  \/p.141<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

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