DOE Fundamentals NUCLEAR PHYSICS AND REACTOR THEORY Module 1 Atomic and Nuclear Physics NUCLEAR PHYSICS AND REACTOR THEORY TABLE OF CONTENTS C TABLE OF CONTENTS ................................................................................................ i LIST OF FIGURES ......................................................................................................iv LIST OF TABLES ......................................................................................................... v REFERENCES ............................................................................................................vi OBJECTIVES .............................................................................................................. vii ATOMIC NATURE OF MATTER .................................................................................. 1 Structure of Matter .................................................................................................... 1 Subatomic Particles .................................................................................................. 2 Bohr Model of the Atom ............................................................................................ 2 Measuring Units on the Atomic Scale ....................................................................... 4 Nuclides .................................................................................................................... 4 Isotopes .................................................................................................................... 5 Atomic and Nuclear Radii ......................................................................................... 6 Nuclear Forces ......................................................................................................... 7 Summary .................................................................................................................. 9 CHART OF THE NUCLIDES ..................................................................................... 11 Chart of the Nuclides .............................................................................................. 11 Information for Stable Nuclides ............................................................................... 12 Neutron - Proton Ratios .......................................................................................... 13 Natural Abundance of Isotopes............................................................................... 14 Enriched and Depleted Uranium ............................................................................. 15 Summary ................................................................................................................ 15 MASS DEFECT AND BINDING ENERGY ................................................................. 17 Mass Defect ............................................................................................................ 17 Binding Energy ....................................................................................................... 18 Energy Levels of Atoms .......................................................................................... 19 Energy Levels of the Nucleus ................................................................................. 20 Summary ................................................................................................................ 21 MODES OF RADIOACTIVE DECAY ......................................................................... 22 Stability of Nuclei .................................................................................................... 22 Natural Radioactivity ............................................................................................... 22 Nuclear Decay ........................................................................................................ 23 I-i NUCLEAR PHYSICS AND REACTOR THEORY Alpha Decay (a) ...................................................................................................... 23 Beta Decay (ẞ) ....................................................................................................... 24 Electron Capture (EC, K-capture) ........................................................................... 24 Gamma Emission (Ɣ) .............................................................................................. 25 Internal Conversion................................................................................................. 26 Decay Chains ......................................................................................................... 26 Predicting Type of Decay ........................................................................................ 27 Summary ................................................................................................................ 29 RADIOACTIVITY ....................................................................................................... 30 Radioactive Decay Rates ....................................................................................... 30 Units of Measurement for Radioactivity .................................................................. 31 Variation of Radioactivity Over Time ....................................................................... 31 Radioactive Half-Life ............................................................................................... 32 Plotting Radioactive Decay ..................................................................................... 35 Radioactive Equilibrium .......................................................................................... 37 Transient Radioactive Equilibrium .......................................................................... 40 Summary ................................................................................................................ 41 NEUTRON INTERACTIONS ...................................................................................... 43 Scattering ............................................................................................................... 43 Elastic Scattering .................................................................................................... 43 Inelastic Scattering ................................................................................................. 45 Absorption Reactions .............................................................................................. 45 Radiative Capture ................................................................................................... 46 Particle Ejection ...................................................................................................... 46 Fission .................................................................................................................... 46 NUCLEAR FISSION .................................................................................................. 48 Fission .................................................................................................................... 48 Liquid Drop Model of a Nucleus .............................................................................. 48 Critical Energy ........................................................................................................ 50 Fissile Material ........................................................................................................ 50 Fissionable Material ................................................................................................ 50 Fertile Material ........................................................................................................ 51 Binding Energy Per Nucleon (BE/A) ....................................................................... 52 ENERGY RELEASE FROM FISSION ....................................................................... 56 I-ii NUCLEAR PHYSICS AND REACTOR THEORY Calculation of Fission Energy ................................................................................. 56 Estimation of Decay Energy ................................................................................... 60 Distribution of Fission Energy ................................................................................. 61 INTERACTION OF RADIATION WITH MATTER ...................................................... 63 Interaction of Radiation With Matter........................................................................ 63 Alpha Radiation ...................................................................................................... 64 Beta-Minus Radiation ............................................................................................. 64 Positron Radiation .................................................................................................. 65 Neutron Radiation ................................................................................................... 65 Gamma Radiation ................................................................................................... 66 Summary ................................................................................................................ 67 I-iii NUCLEAR PHYSICS AND REACTOR THEORY LIST OF FIGURES Figure 1 Bohr's Model of the Hydrogen Atom ................................................................ 3 Figure 2 Nomenclature for Identifying Nuclides ............................................................