501503742 Nuclear and Radiation Physics Why nuclear physics? Why radiation physics? Why in Jordan? Interdisciplinary. Applied? 1
Subjects to be covered Nuclear properties. Nuclear forces. Nuclear matter. Nuclear models and shell structure of the nucleus. Radioactive decays. Interactions of nuclear radiations (charged particles, gammas, and neutrons) with matter. Nuclear reactions: energetics and general cross-section behavior. Binding energy and nuclear stability, fission and fusion. This course (phenomenological) will be followed by other nuclear physics courses: Theoretical nuclear physics. Experimental techniques in nuclear physics... 2
Level Test 1. Write down whatever you know about the semiempirical mass formula. 2. Describe how can either fission or fusion produce energy. 3. What is 1. Bremsstrahlung? 2. Energy straggling? 3. Pair production? 4. Time-of-flight technique? 5. Isotopes, Isotones, Isobars, Isomers? 3
Grading First Exam 10% Second Exam 10% Project and HWs 30% Final Exam 50% 4
Proposed Projects Experiments to determine nuclear properties. Nuclear power generation. Nuclear medicine. Health physics. Accelerator driven systems. Nucleosynthesis. Technological applications (e.g. Material Science). Radioactive ion beams. Neutrino physics. Radiological dating. Environmental radioactivity. Feynman diagrams... (your own selected subject). Decide on the title of your project within one week. Written + presentation. 5
Scale and Objectives Nuclear scale: Order of magnitude of 1 x 10-15 m = 1 femtometer = 1 fm = 1 fermi. Too small for direct investigation. We need to answer.. 1. What are the building blocks of a nucleus? 2. How do they move relative to each other? 3. What laws governing them? We need to understand: Nuclear forces (Q2, Q3). Nuclear structure (Q2, Q3). We also need High Energy Physics (to answer Q1). 6
Constants http://physics.nist.gov/cuu/constants/index.html 7
Nomenclature Element vs. Nuclide. 94 natural chemical elements, total > 100. Element Atomic number (Z) chemically identical. 3000 nuclides. Same Z but different neutron number (N) Isotopes. Total number of nucleons = Z+N = A mass number. A Z X N A X 22 11 23 Na Na 11 24 Na Radioactive Stable Radioactive Chart of Nuclides Same mass number Isobars chemically dissimilar, parallel nuclear features (Radius ). β decay. Same neutron number Isotones?????. Am Same Z and same A Isomers metastable. X Stable isotope (Isotopic) Abundance. Radioactive isotope Half-life. 8
Stable Isotopes HWc 1 Odd A Even A Isotope N Z N Z Then plot Z vs. N. Odd A Even A 9
Basic Nuclear Properties The energy of the nucleon in the nucleus is in the order of 10 MeV. HW 1 Calculate the velocity of a 10 MeV proton and show that it is almost 15% of the speed of light. (Perform both classical and relativistic calculations). Relativistic effects are not important in considering the motion of nucleons in the nucleus. HW 2 Calculate the wavelength of a 10 MeV proton and compare it with the nuclear scale. (Perform both classical and relativistic calculations). Is the nucleus thus a classical or a quantum system? HW 0 Krane, Ch. 2. HW 3 Calculate the wavelength for an electron of the same energy to show that it is much too large to be within the nucleus. (Perform both classical and relativistic calculations). 10
Basic Nuclear Properties Static nuclear properties (Time-independent): Electric charge, radius, mass, binding energy, angular momentum, parity, magnetic dipole moment, electric quadrupole moment, energies of excited states. Dynamic properties (Time-dependent): Self-induced (Radioactive decay). Forced (Nuclear reactions). The key: Interaction between individual nucleons. Excited states: atomic intervals ~ ev. nuclear intervals ~ 10 4 10 6 ev. Decays and reactions: Conservation laws and selection rules. 11