Non-reciprocity in elastic unpolarized neutron scattering by systems   with non-coplanar magnetic structure
  The paper provides a theoretical analysis for elastic unpolarized neutron scattering by systems having a non-coplanar magnetic induction spatial distribution. It is shown that reciprocity does not hold for neutron scattered by these systems. The scattering of unpolarized neutrons by a system of three magnetic mirrors and by a ferromagnetic particle in a "vortex" state is also explored. 
D.A. Tatarsky, O.G. Udalov, A.A. Fraerman
cond-mat.other