Nucleon

From Memory Alpha, the free Star Trek reference.

Nucleon is the name given to particles within the nucleus of an atom (i.e. protons and neutrons).

Element 247, discovered by the crew of the USS Voyager in the ring of a gas giant in the Delta Quadrant, is a stable element with an unusually large atomic mass and over 550 nucleons. (VOY: "Emanations")

Nucleonics
nucleonic beam - nucleonic interference - nucleonic particle - nucleonic radiation