The antineutron was discovered in proton–antiproton collisions at the Bevatron (Lawrence Berkeley National Laboratory) by the team of Bruce Cork, Glen Lambertson, Oreste Piccioni, and William Wenzel in 1956,[2] one year after the antiproton was discovered.

Since the antineutron is electrically neutral, it cannot easily be observed directly.

In theory, a free antineutron should decay into an antiproton, a positron, and a neutrino in a process analogous to the beta decay of free neutrons.

There are theoretical proposals of neutron–antineutron oscillations, a process that implies the violation of the baryon number conservation.

[3][4][5] The magnetic moment of the antineutron is the opposite of that of the neutron.