Stable spin precession at one half of equilibrium magnetization in superfluid 3He-B

New modes of spin precession have been observed in superfluid 3He−B with a precessing magnetization M=pMeq, where p=1, 12, and ≈0. These dynamic order parameter states are the first examples of stable precession with a magnetization different from the equilibrium value Meq. The p=12 mode is the second example of a phase-coherent state of a spin superfluid. The new states can be excited close to Tc in the range 1−T/Tc≲0.02 where dissipation is low and the energy barriers between the different local minima of the spin-orbit energy are small.