Nucleus

1. Nucleus

2. The nucleus consists of protons and neutrons. Protons: Z (atomic number) Neutrons: N Nucleons: A = Z + N (atomic mass) Full notation shows A, Z Chemical symbol duplicates atomic number. Short notation – A only Nuclear Notation

3. All nuclei have about the same density r. Independent of A The nucleus is roughly a sphere. Radius r, r0= 1.2 fm Volume V Nuclear Size

4. Nuclei that have the same proton count are isotopes. Isotones for identical neutron count Isotopes

5. Nuclear States

6. Energy measurements for nuclear physics are built on the electron volt (eV). 1 eV = 1.6  10-19 J Mass is expressed in terms of the rest energy. Mass is also expressed in terms of nucleons. Atomic mass unit (u) Based on 12C 1 u = 931.5 MeV/c2 Proton, p 938.3 MeV/c2 1.007 u Neutron, n 939.6 MeV/c2 1.009 u Electron, e 0.511 MeV/c2 5.546  10-4 u Atomic Mass

7. The mass (M) in u is nearly equal to the atomic number (A). Tables of isotope data frequently list D = M – A. Binding energy 1H; D = 7.29 MeV 4He; D = 2.42 MeV 56Fe; D = – 60.60 MeV 214Pb; D = – 0.15 MeV 218Po; D = 8.38 MeV 222Rn; D = 16.39 MeV 226Ra; D = 23.69 MeV Mass Difference

8. Binding Energy next