Antineutronball

Antineutronball is the Antiparticleball of Neutronball. He differs from Neutronball only in that some of his properties have equal magnitude but opposite sign. He has the same mass as Neutronball, and no net electric charge, but has opposite baryon number (+1 for neutron, −1 for the antineutron). This is because the he is composed of antiquarkballs, while Neutronballs are composed of quarkballs. The antineutron consists of one Up Antiquarkball and two Down Antiquarkballs.

Since he is electrically neutral, he cannot easily be observed directly. Instead, the products of his annihilation with ordinary matterballs are observed. In theory, a free Antineutronball should decay into an Antiprotonball, a Positronball and a Neutrinoball in a process analogous to the beta decay of free Neutronballs. There are theoretical proposals of Neutronball–Antineutronball oscillations, a process that implies the violation of the baryon number conservation.

He was discovered in Protonball–Antiprotonball collisions at the Bevatron (Lawrence Berkeley National Laboratory) by Bruce Cork in 1956, one year after Antiprotonball was discovered.