The worldsheet low-energy limit of the AdS4×CP3 superstring

We consider the AdS4×CP3 IIA superstring sigma-model in the background of the “spinning string” classical solution, which possesses two Noether spins. In the limit when one of the spins is infinite there are massless excitations, which govern the infrared worldsheet properties of the model. We obtain a sigma-model of CP3 with fermions, which describes the dynamics of these massless modes.