The Nilsson model of these objects explains the observation from rotational spectra that the majority of them are prolate. Wigner used random matrices to describe the distribution of energy-level spacings in the spectra of these objects. They're not molecules, but "isomers" of these objects are often metastable because relaxation is extremely spin-forbidden, and are labeled with an "m." Interactions with the spin of these objects, symbolized I, leads to (*) hyperfine structure. (-5[1])The semi-empirical mass formula predicts a peak around A equals 56 for the binding energy of these objects. The existence of these structures was suggested by their scattering of alpha particles in Rutherford’s (10[1])gold foil experiment. For 10 points, name these structures consisting of protons and neutrons that lie at the center of atoms. ■END■ (10[1])