Atomic and Nuclear physics 152 Nuclear physics 151 Physics 139 Particles (Nuclear physics) 76 Modern physics 56 Radioactivity 22 Atomic physics 20 Atoms 20 Nuclear reactions 20 Nuclear Physics 18 Quantum theory 17 RADIATION 17 Molecular physics 15 Radiation 14 Molecules 13 Particle physics 13 Quantum chromodynamics 12 Atom 11 Nuclear energy 11 Molecular spectroscopy 10 Molecular spectroscopy; Nuclear structure; Atomic and Nuclear physics 10 Nuclear counters 10 Nuclear structure 10 Nucleus 10 Atomic structure 9 Microclusters 9 Neutrinos 9 Electromagnetic waves 8 Measurement 8 String models 8