Protons and neutrons, which are particles known as nucleons, are primarily found within the atomic nucleus. They do not possess distinct orbital sizes like electrons, which are associated with quantized energy levels in atoms.
The behavior of protons and neutrons within the nucleus is described by nuclear models such as the nuclear shell model or the liquid drop model. These models consider the nucleons as occupying energy levels within the nucleus, much like the electron energy levels in an atom.
In the nuclear shell model, nucleons are assigned to energy levels called shells, which are analogous to electron shells in atoms. Each shell can accommodate a certain number of nucleons. The size of the nuclear shells increases with increasing energy, and nucleons occupy these shells in a way that minimizes their total energy.
The smallest nuclear shells typically found in stable nuclei are the 1s and 1p shells. The 1s shell can accommodate up to 2 nucleons, while the 1p shell can accommodate up to 6 nucleons. However, it's important to note that the behavior of nucleons in the nucleus is more complex than that of electrons in atoms, and their interactions involve strong nuclear forces.
In terms of spatial extent, the nucleons themselves are not point-like particles, but they are described by wave functions that represent their probability distributions within the nucleus. The exact size of these distributions depends on the specific energy state and the dynamics of the nucleus as a whole.
In summary, while protons and neutrons do not possess distinct orbital sizes like electrons, they do occupy energy levels within the atomic nucleus. The smallest nuclear shells typically found in stable nuclei are the 1s and 1p shells, which can accommodate up to 2 and 6 nucleons, respectively. The spatial extent of nucleons within the nucleus is described by their wave functions, which depend on the specific energy state and dynamics of the nucleus.