NEUTRON SPIN-REORIENTATION EXPERIMENTS

Neutron spin-reorientation experiments which give fundamental physics information are described. The magnetic moment of the neutron has been measured to be 1.91304275(45) nuclear magnetons by separated oscillat ory fields resonant reorientation's of the spins of neutrons in a beam passing through a magnetic field. In similar resonance experiments wi th ultracold neutrons trapped in a bottle, the neutron electric dipole moment has been shown to be less than 9x10(-26) e Cm. Neutrons ''dres sed'' with many radio frequency quanta have been studied. The Berry ph ases of neutrons that have gassed through a helical magnetic field or an oscillatory magnetic field have been observed. In neutron interacti ons experiments with condensed matter, small changes in neutron veloci ties have been measured by changes in the neutron precessions in magne tic fields before and after the interaction. Parity non-conserving spi n rotations of neutrons passing through various materials have been ob served and measured and new experiments with H-2 and He are in progres s. (C) 1998 Elsevier Science B.V. All rights reserved.