Spin polarisabilities of the nucleon at NLO in the chiral expansion
  We present a calculation of the fourth-order (NLO) contribution to spin-dependent Compton scattering in heavy-baryon chiral perturbation theory, and we give results for the four spin polarisabilities. These results have been presented before, in hep-ph/0002133. Here we address the issue of whether one-particle reducible graphs in the heavy baryon theory contribute to the polarisabilities. 
Judith A. McGovern, Michael C. Birse and K. B. Vijaya Kumar