Spin polarizabilities and characteristics of spin-one hadrons related   parity non-conservation in the the Duffin-Kemmer-Petiau formalism
  In this paper the method of the relativistically-invariant effective tensor representation of Lagrangian decomposition and the amplitudes of the two-photon interaction with hadrons on photon energy is proposed. In the frames Duffin-Kemmer-Petiau formalism based on this method the spin polarizabilities of the spin 1 particles, which are characteristic for the spin 1/2 hadrons were established. Also the authors have obtained the new spin polarizabilities which are characteristic for spin 1 particles and are bounded with the presence of the tensor polarizabilities of these particles. It was shown that in the suggested covariant approach with regard to the crossing symmetry, the spatial parity, conservation laws and gauge invariance definite spin polarizabilities and gyrations of spin-1 particles contribute to the expansion of Compton scattering amplitude, starting from the corresponding orders on photon energy that is in the agreement with low-energy theorems for that process. 
N.V. Maksimenko, E.V. Vakulina
hep-ph