Two-dimensional S-matrices from unitarity cuts

Bianchi, L., Forini, V. ORCID: 0000-0001-9726-1423 & Hoare, B. (2013). Two-dimensional S-matrices from unitarity cuts. Journal of High Energy Physics, 2013, 88. doi: 10.1007/JHEP07(2013)088

Abstract

Using unitarity methods, we compute, for several massive two-dimensional models, the cut-constructible part of the one-loop 2 → 2 scattering S-matrices from the tree-level amplitudes. We apply our method to various integrable theories, finding evidence that for supersymmetric models the one-loop S-matrix is cut-constructible, while for models without supersymmetry (but with integrability) the missing rational terms are proportional to the tree-level S-matrix and therefore can be interpreted as a shift in the coupling. Finally, applying our procedure to the world-sheet theory for the light-cone gauge-fixed AdS5 × S 5 superstring we reproduce, at one-loop in the near-BMN expansion, the S-matrix known from integrability techniques.