An Exact Solution of Gauged Thirring Model in Two Dimensions ∗

In two space-time dimensions, we write down the exact and closed Schwinger-Dyson equation for the gauged Thirring model which has been proposed recently by the author. The gauged Thirring model is a natural gauge-invariant extension of the Thirring model and reduces to the Schwinger model (in the Abelian case) in the strong four-fermion coupling limit. The exact SD equation is derived by making use of the transverse Ward-Takahashi identity as well as the usual (longitudinal) Ward-Takahashi identity. Moreover the exact solution of the SD equation for the fermion propagator is obtained together with the vertex function in the Abelian gauged case. Finally we discuss the dynamical fermion mass generation based on the solution of the SD equation.