Three-dimensional magnetic confinement of neutrons is reported. Neutrons are loaded into an Ioffe-type superconducting magnetic trap through inelastic scattering of cold neutrons with ${}^4\mathrm{He}.$ Scattered neutrons with sufficiently low energy and in the appropriate spin state are confined by the magnetic field until they decay. The electron resulting from neutron decay produces scintillations in the liquid helium bath that results in a pulse of extreme ultraviolet light. This light is frequency downconverted to the visible and detected. Results are presented in which $500\pm 155$ neutrons are magnetically trapped in each loading cycle, consistent with theoretical predictions. The lifetime of the observed signal, ${660}_{-170}^{+290\mathrm{}}\hspace{0.5em}\mathrm{s},$ is consistent with the neutron beta-decay lifetime.

• Received 13 December 2000

DOI:https://doi.org/10.1103/PhysRevC.63.055502