  In the present paper the equations for the spin evolution of a particle in a
storage ring are analyzed considering contributions from the tensor electric
and magnetic polarizabilities of the particle. Study of spin rotation and
birefringence effect for a particle in a high energy storage ring provides for
measurement as the real part of the coherent elastic zero-angle scattering
amplitude as well as tensor electric and magnetic polarizabilities.
  We proposed the method for measurement the real part of the elastic coherent
zero-angle scattering amplitude of particles and nuclei in a storage ring by
the paramagnetic resonance in the periodical in time nuclear pseudoelectric and
pseudomagnetic fields.
