Integrability of the gauged linear sigma model for AdS ₅ × S ⁵

Recently, a gauged linear sigma model was proposed by Berkovits and Vafa which can be used to describe the AdS ₅ × S ⁵ superstring at finite and zero radius. In this paper we show that the model is classically integrable by constructing its first non-local conserved charge and a superspace Lax ''quartet''. Quantum conservation of the non-local charge follows easily from superspace rules.