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10 Nuclear Physics 10.1 Properties of the Nucleus 10.1.1 Nomenclature We define: Z = number of protons in the nucleus, TV = number of neutrons in the nucleus, A = N + Z= number of nucléons. Nuclides with identical Z are called isotopes, nuclides with identical N are called isotones, nuclides with identical A are called isobars. Protons, neutrons, and the particles that hold them together — n mesons — are the only particles believed to exist in the atomic nucleus. When other particles are observed to come from the nucleus (such as alpha, beta, or gamma

CHAPTER FIVE Experimental Nuclear Physics We were struck by the surprisingly large number of almost straight line electron tracks emanating from the source. In the 1 920S it was possible, indeed essential, for a scientist to have a detailed overview of the field of nuclear physics. In this Lise Meitner was typical, closely following the experiments and theoretical work of others, writing review articles, speculating on the significance of new developments. Even at the height of her controversy with C. D. Ellis, she undertook a variety of other

antiprotonic x-rays also give information on the neutron density in the nuclear periphery. The combined evaluation of both mentioned methods is expected to improve our knowledge in this field. First experiments this year seem to indicate a strong change of the last antipro- T. von Egidy et al. ■ Nuclear Physics with Antiprotons ] ♦Yb1 1 j Th Jle Zri i154Sm Sm i Ru *Ni I c 3 JO I«<0 TJ lu > . p (a I rest) + 1 An O p (0t 1 CeV) + i97Au I q5 °0 / ' V a** f 0 20 40 60 60 100 120 HO 160 180 200 Mass N u m b er 0.1 • p (at 1,2 CeV) Au O p (al 6 CeV) + Au b & * o j H j

Chapter 7 Nuclear Physics P roblem 7.1. A proposed geologic solar neutrino detector utilizes 205T1 as the target material (70% of natural thallium). Thallium- bearing ore would be searched for 205Pb {t\/2 = 14 million years), created by neutrino captures. a) The state structure in A — 205 is given in Figure 7.1. Explain the states in terms of a simple shell model. b) In order to determine the cross-section for neutrino capture to the 1/2 - state of 205Pb, one needs to look at the A = 206 system also shown in Figure 7.1. Again, explain the observed

Nuclear Physics 5.1 Rotational States In early work on the structure of nuclei in the late thirties and forties, there was much speculation whether a nucleus could have rotational states like a solid body or a molecule. Some learned pa- pers tried to prove that there could be no such states. The argu- ments used in these papers are too complicated to summarize here. There were, however, two reasons that had many of us believing there should be no rotational states. One was that experiments on nuclear excitation had not given any indication of such states. (We now

Nuclear Physics 1 On the Problem of the Chain Decay of the Main Uranium Isotope* With Yu. B. Khariton In this work we consider the problem of the moderation of neutrons which form in uranium decay and of the conditions necessary for the chain decay of uranium. For the chain decay of the main uranium isotope to be possible it is essential that the neutrons which form in the fission of the uranium atom manage with sufficient probability to induce the next decay event, not only before they leave the mass of the uranium involved in the decay [1], but also

1 Introduction Cancer is one of the most lethal diseases. Radiotherapy is currently one of the main means of liver cancer treatment. Radiobiologists study the radiation effects of different kinds of nuclear physics rays on hepatocellular carcinoma cells as the main objective to determine the radiation results and efficacy of different nuclear physics rays on hepatocellular carcinoma cells [ 1 , 2 ]. Accurate research on radiation effects of hepatocellular carcinoma cells can not only provide theoretical basis for cancer treatment, but also provide great help for

Chapter 16 Nuclear Physics— Solutions Solution 7.1. a) The ground state of 2g®Tl has proton and neutron configuration p [82] (3s1/2) _1 n f i1 x n [126] (3p1/2) -2 , where [A;] denotes a closed, inert core of k nucleons, and (• • •)~1 denotes a “hole” in that core. There are two neutron holes, which will pair so that their combined wavefunction has total spin zero and positive parity. Thus the properties of the ground state are determined by the lone proton hole, which has orbital angular momentum / = 0 , parity 7r = (—1)J = + 1, and spin 1/2, so that J