略語大辞典 [Phys] 19 UCN ultra-cold neutron 程度の中性子.ultra-cold neutron; neutrons of extremely low kinetic energies on the order of about 10-7 eV, which correspond to typical effective neutron potential energies arising from the coherent scattering of neutrons by the nuclei in condensed matter; c 丸善「略語大辞典」JLogosID : 11852877