Dynamical superfield theory of free massive superspin-1 multiplet

We construct an N=1 supersymmetric Lagrangian model for the massive superspin-1 superfield. The model is described by a dynamical spinor superfield and an auxiliary chiral scalar superfield. On-shell this model leads to a spin-12, spin-32 and two spin-1 propagating component fields. The superfield action is given and its structure in the fermionic component sector is presented. We prove that the most general theory is characterized by a one parameter family of actions. The massless limit is shown to correspond to the dynamics of both the gravitino and superhelicity-12 multiplets.