Extended class of Dubrovinʹs equations related to the one-dimensional quantum three-body problem

The relation of the quantum 1D three-body problems with zero-range interaction to the matrix Riemann-Hilbert problem with meromorphic coefficient is shown. The solution of this problem is discussed using the exact analytic diagonalization of the coefficient. The problem is reduced to the boundary value problem on the Riemann surface. The solution of this problem is expressed in terms of the Riemann theta-functions. An extended class of integrable Dubrovinʹs type ordinary differential equations related to the one-dimensional quantum three-body problem is derived.