Nucleon spin polarizability at orderO(p4)in chiral perturbation theory

We calculate the forward spin-dependent photon-nucleon Compton amplitude as a function of photon energy at next-to-leading $\left({O(p}^4\right))$ order in chiral perturbation theory, from which we extract the contribution to the nucleon spin polarizability. The result shows a large correction to the leading order contribution.