Bethe Ansatz solution of the stochastic process with nonuniform stationary state

The eigenfunctions and eigenvalues of the master-equation for zero range process on a ring are found exactly via the Bethe ansatz. The rates of particle exit from a site providing the Bethe ansatz applicability are shown to be expressed in terms of single parameter. Continuous variation of this parameter leads to the transition of driving diffusive system from positive to negative driving through purely diffusive point. The relation of the model with other Bethe ansatz solvable models is discussed.