STUDY GUIDE. 2. Explain and use the special nuclear units of ev and amu and their conversion to SI units.

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1 STUDY GUIDE NE 495: Elements of Nuclear Engineering Chapter 1: Fundamental Concepts 1. Use SI units, their abbreviations, prexes, and grammar. 2. Explain and use the special nuclear units of ev and amu and their conversion to SI units. 3. Use Table 1.5 to nd values of fundamental physical constants. 4. Explain or dene special atomic and nuclear nomenclature such as nuclide, atomic weight, mole, Avogadro's number, isobar, isotone, isomer, and isotope. 5. Convert between number of atoms and mass of a substance. 6. Know the size of atoms and nuclei. 7. Use the Chart of the Nuclides to obtain information about specic nuclides. 8. Use the web to nd nuclear and atomic data. Chapter 2: Modern Physics Concepts 1. Explain the reason Einstein developed his special theory of relativity. 2. Explain the meaning and importance of the results of special relativity: (1) E = mc 2 (2) relativistic mass, (3) relativistic length contraction, and (4) relativistic time dilation. 3. Use the relativistic relations to nd speeds, masses and kinetic energies of relativistic particles. 4. Express a particle's momentum in terms of its kinetic energy, both relativistically and classically. 5. Describe the results and importance of the photoelectric eect. 6. Calculate the energy and momentum of a photon in terms of its frequency. 7. Describe the signicance of Compton scattering. 8. Use the Compton formula to determine the energy and angle of photons scattered by electrons. 9. Explain the signicance of wave-particle duality. 10. Describe how the Davisson-Germer electron scattering experiment conrmed the wave-nature of electrons. 11. Describe the basic idea used by Schrodinger to derive his famous wave equation. 12. Explain the important consequences of Schrodinger's wave equation and why it is the basis of quantum mechanics. 13. Explain the meaning of the wave function of a particle. 14. Describe, explain, and use the Heisenberg uncertainty principle. 1

2 Chapter 3: Atomic/Nuclear Models 1. Describe the discovery of radioactivity and how the three types of associated radiation (alpha, beta, and gamma) dier. 2. Describe Thomson's plum pudding model of an atom, what it explained, and what it could not explain. 3. Describe the Rutherford atomic model, what it explained over the Thomson model, and what it could not explain. 4. Describe the postulates Bohr used for his atomic model. 5. Quantify the radii and energies of electrons in the Bohr orbits. 6. Calculate the wavelengths and energies of photons in the various hydrogen spectrographic series. 7. Explain why the Bohr model needed to be rened. 8. Explain why Bohr-like models of the atom gave way to a quantum mechanical description of the bound electrons. 9. Calculate the radii of nuclei of dierent mass numbers. 10. Describe the proton-electron model of the nucleus, what it could explain, and why it is decient. 11. Describe the neutron-proton model of the nucleus and why it is superior to the proton-electron model. 12. Describe qualitatively how the nuclear and electromagnetic force and potential energy between two nucleons varies as a function of the distance between them. 13. Describe properties of stable nuclei such as N vs Z, pairing of nucleons, maximum Z, etc. 14. Explain the variation of (Z; A) of nuclei in the valley of stability in the Chart of the Nuclides. 15. Describe the liquid drop model of the nucleus. 16. Explain and quantify the various contributions to the nuclear binding energy used in the liquid drop model. 17. Explain the term \magic numbers" and how they arise. Chapter 4: Nuclear Energetics 1. Explain how Einstein's relation E = mc c can be used to determine the energy emitted or absorbed in any reaction. 2. Explain why the energetics of only nuclear reactions can, in practice, be determined from the mass change of the reactants. 3. Explain the concept of binding energy. 4. Quantify the relation between nuclear and atomic masses. 5. Use data in Appendix B to nd atomic masses. 6. Calculate the binding energy of any nuclide. 7. Sketch the variation of average BE per nucleon versus the atomic number of the nuclides. 2

3 8. Explain from the BE/A vs A curve how fusion and ssion reactions can be used to extract energy from nuclei. 9. Calculate the energy emitted in fusion and ssion reactions. 10. Contrast the energy emitted in chemical and nuclear reactions. 11. Explain what is meant by binding energy, neutron separation energy and proton separation energy; compute these energies. 12. Explain radiative decay and binary nuclear reactions. 13. Write binary reactions in both long and short forms and use conservation principles to identify any missing reactant information such as Z, A or chemical symbol. 14. Explain the meaning of the Q-value of a nuclear reaction. 15. Calculate the Q-value for any nuclear reaction. 16. Explain the signicance of positive and negative Q-values. 17. Relate the Q-value to mass changes and kinetic energy changes of the reactants. Chapter 5: Radioactivity 1. Describe and write the decay reactions for the various types of radioactive decay. 2. List the physical quantities conserved in radioactive decay. 3. Calculate the Q-value for any type of radioactive decay. 4. Use the Q-value to quantify the kinetic energy of the decay products. 5. Explain why the neutrino was postulated as a product of beta decay. 6. Use energy level diagrams to obtain radioactive decay data. 7. Describe quantitatively the competing nature and energetics of + and EC decay. 8. Explain which types of radioactive decay produce monoenergetic decay products and which produce decay products with a distribution of energies. 9. Dene and explain the meaning of the \decay constant" for a radionuclide. 10. Derive the radioactive decay equation and its solution. 11. Explain the exponential decay law and why it arises. 12. Explain what is meant by a sample's \activity," the units used to quantify it, and the relation of activity to the number of radionuclides in the sample. 13. Quantify the relation between the decay constant, half life, and mean life of a radionuclide. 14. Analyze radioactive decay data to obtain the half-life. 15. Quantify the relations between the activity, number of radionuclides, and mass of the radionuclides in a sample. 16. Calculate the decay probabilities and decay constants for competing decay modes of a radionuclide. 17. Calculate the number of atoms or activity of a sample with both decay and production of the radionuclides. 3

4 18. Write the decay equations for a radioactive decay chain. 19. Use the solutions for a 3-component decay chain to quantify the activities and decay times of the parent, daughter, and stable granddaughter. 20. Explain and approximate the decay dynamics if the parent's half-life is much greater or much less than that of the daughter radionuclide. 21. Explain the term \secular equilibrium" and its importance in primordial decay series. 22. Calculate the age of a sample from activity measurements. 23. Use data in Appendix A, Table 5.2 and Figs and 5.20 to obtain the half-lives and decay constants for various radionuclides. Chapter 6: Binary Nuclear Reactions 1. List physical quantities conserved in all nuclear reactions. 2. Describe the reaction process and the dierence between direct interactions and reactions in which a compound nucleus is formed. 3. Explain what is meant by transfer reactions, scattering reactions, knockout reactions, capture reactions, and nuclear photoeect reactions. 4. Write equations that describe the conservation of total energy and linear momentum for binary, two-product reactions. 5. Apply the results of reaction kinematics to quantify the energy and direction of particle emission in terms of incident particle energy. 6. Explain and calculate kinematic and Coulombic threshold energies for exothermic and endothermic reactions. 7. Apply kinematic results to various types of binary reactions such as heavy particle scattering from electrons and neutron scattering from nuclei. 8. Calculate maximum and minimum energy losses in neutron elastic and inelastic scattering. 9. Describe various reactions caused by neutrons and their importance. 10. Describe the ssion process. 11. Explain what is meant by ssile, ssionable and fertile isotopes. 12. Explain the process by which prompt neutrons, prompt gamma rays, and ssion product chains are produced. 13. Quantify the energy emitted in a ssion and how it is distributed among the products of ssion. 14. Explain and quantify the yield of ssion-product decay chains. 15. Quantify the kinetic energy of the light and heavy ssion fragments. 16. Quantify the number and energy of ssion neutrons. 17. Explain the origin of delayed neutrons and their importance. 18. Quantify prompt and delayed ssion energy. 19. Calculate the energy emission rate from ssion products as a function of time after ssion. 4

5 20. Calculate ssion energetics from masses of reactants. 21. Use conversion factors relating (1) ssion rate and thermal power (1 W = 3: ssion/s) and (2) ssion power and mass consumed/ssioned (1 MWd= 1:24 g of 235 U consumed). 22. Explain exothermic fusion reactions and calculate the energy emitted. 23. Explain the need for plasmas to produce fusion reactions and methods that can he used to conne such plasmas. 24. Describe the energy production mechanism in stars. 25. Describe the evolution, from birth to death, of stars. 26. Describe how the dierent naturally occurring nuclides were formed. Chapter 7: Radiation Interactions with Matter 1. Explain what is meant by directly ionizing radiation and indirectly ionizing radiation. 2. Explain the dierence in trajectories of changed and uncharged particles as they traverse a material. 3. Explain the meaning of the interaction coecient for neutral particles. 4. Quantify the exponential attenuation of uncollided photons or neutrons as they traverse a medium. 5. Quantify the probability a photon or neutron does and does not interact while traveling a distance x. 6. Calculate the average travel distance of a neutron or photon before interacting. 7. Calculate a material's half-thickness for attenuating neutral particles. 8. Use a buildup factor to obtain the total radiation intensity from the uncollided intensity. 9. Explain the concept of the microscopic cross section. 10. Calculate the interaction coecient for various reactions in terms of the microscopic cross sections. 11. Calculate interaction coecients for mixtures and compounds. 12. Explain the physical meaning of ux density. 13. Calculate reaction rate densities R =. 14. Calculate uence from ux density. 15. Calculate the ux density arising from a point isotropic source with and without material attenuation. 16. Describe the principal photon interaction mechanisms and the secondary radiation produced by each. 17. Sketch the variation of the dierent photon interaction cross section with photon energy. 18. Use the Compton formula to express the relation between the incident and scattered photon energies. 19. Obtain various photon interaction coecients from the data in Appendix C. 5

6 20. Explain the meaning of the energy absorption coecient, how its is related to the other photon interaction coecients, and why it is important. 21. Describe the various types of neutron interactions and why they are important in reactors. 22. Describe the variation of the total neutron cross section with neutron energy and nuclide. Contrast this variation with that for photon cross sectins. 23. Use graphs in Ch. 7 and data in Appendix C to obtain values for neutron cross sections. 24. Explain what is meant by thermal ssion and fast ssion. 25. Describe the mechanisms for energy loss of charged particles as they pass through matter. Consider both heavy charged and electrons. 26. Describe the dierences between the paths of electrons and heavy charged particles. 27. Explain the term stopping power, collisional stopping power, and radiative stopping power. 28. Compute the range of charged particles in various media. 29. Compute the range of ssion products. 30. Explain why charged particles have nite ranges but neutron and photons do not. 31. Explain how photons, neutrons and charged particles transfer their energy to the medium they traverse. Chapter 8: Radiation Detection Not part of this course. Skim if you are interested in the topic. Chapter 9: Radiation Doses and Hazard Assessment 1. Name at least three international/national organizations responsible for assessing the eects of radiation on humans and recommending exposure standards. 2. Explain the dierence between absorbed dose and the kerma. 3. Explain why the kerma is easier to calculate than the absorbed dose. 4. Explain under what conditions the kerma equals the absorbed dose. 5. For a given uence of photons or neutrons, calculate the absorbed dose in grays and rads. 6. Explain why exposure is a kerma-like quantity. 7. Explain the dierence between relative biological eectiveness and the quality factor. 8. Explain why the quality factor for alpha particles is greater than that for gamma rays. 9. Use the quality factor to convert the absorbed dose into the eective dose equivalent in units of sieverts and rems. 10. Explain the use of tissue weighting factors and what they indicate about the radiosensitivity of the various organs/tissues in the human. 11. Quantify the average U.S. annual absorbed dose and list the various sources that lead to this exposure. 12. Describe how various organs of the human body react to large acute doses of radiation. 6

7 13. Explain why the same dose delivered at lower dose rates causes smaller biological eects. 14. Describe the physical mechanisms whereby ionization radiation leads to damage in biological cells. 15. Quantify lethal radiation doses for humans and describe the mechanisms that lead to death. 16. Describe and quantify the natural occurrence of various types of hereditary disease. 17. Use estimates of radiation-induced cases of hereditary illness to quantify the risk that an individual, who receives a radiation gonad dose, will produced a child with a birth defect caused from the radiation exposure. 18. Explain the dierence between the number of cases of hereditary illness in all future generations arising from a one-time exposure to a single generation is related to the number of equilibrium hereditary illness cases arising from each generation receiving the same radiation dose. 19. Estimate the risk of radiation-induced cancer mortality for individuals receiving a radiation dose of varying magnitude at various ages. 20. Explain why radon is of concern to people living in houses. 21. Explain the mechanism responsible for radon-induced lung cancer. 22. For a person exposed to a given radon concentration, estimate his or her risk of death from radiogenic lung cancer. 23. Describe the uncertainties in the radiation risk models and their implications to assessing risks of low doses to individuals. 24. State the occupational and public annual radiation limits for stochastic health eects. Chapter 10: Principles of Nuclear Reactors 1. Explain what is meant by a \thermal" and a \fast" reactor. 2. Explain the role of a moderator in a reactor core and list at least four properties a good moderator should have. 3. Describe what nuclear properties of ssile and ssionable isotopes are desired for use a fuel in a thermal reactor. 4. Sketch the neutron life cycle in a thermal reactor and indicate the various events that befall neutrons as move through this cycle. 5. Explain the meaning and importance of k eff. 6. Dene in words each of the factors in the six-factor formula k eff = pfp f NL P th NL. 7. For a given fuel/non-fuel composition, calculate f and for a homogeneous core material. 8. Sketch how the four factors in the four-factor formula k1 = pf vary with the fuel-tomoderator ratio. 9. Explain why there is an optimum fuel-to-moderator ratio. 10. Describe the eect on the four factors, p,, and f when the fuel is lumped together, i.e., a heterogeneous versus a homogeneous core. 11. Explain why most reactors use fuel enriched in 235 U. 7

8 12. Explain why and how a reector around a core is used for small cores. 13. Explain the origin and importance of delayed neutrons. 14. Explain what is meant by reactivity and the special units used to quantify reactivity. 15. Explain what is meant by the reactor period. 16. Quantify the reactor period for large and small departures from criticality. 17. Sketch a power transient for dierent reactivity insertions into a steady-state critical reactor and explain the asymptotic power behavior. 18. Explain what is meant by the phrase \poisoning out the reactor." 19. Explain the importance and origin of reactivity feedback in a reactor. 20. Explain the origin and importance of xenon poisoning in a thermal reactor. 21. Explain how the various factors in the six-factor formula change in response of changes in core composition, enrichment, shape, and temperature and how k eff is changed. 8