What particles are found in the nucleus of an atom?

The nucleus of an atom is composed of protons and neutrons. Protons are positively charged particles, which determine the element's identity and its atomic number. Neutrons, on the other hand, are electrically neutral and contribute to the atom's mass. Together, protons and neutrons are known as nucleons, and they are held together in the nucleus by the strong nuclear force.

Electrons, while they are fundamental constituents of atoms, reside in orbitals outside the nucleus and are not found within it. Positrons, which are the antimatter counterparts of electrons, do not typically exist in a stable atom's nucleus. The presence of both protons and neutrons is crucial in defining the stability of the nucleus and the overall characteristics of the atom.