Convergence Rate Estimates for an Iteratively Regularized Gradient Method with an a Posteriori Stopping Rule

We study an iteratively regularized gradient method with an a posteriori stopping rule for solving nonlinear irregular operator equations in Hilbert spaces. An accuracy estimate in terms of the error level of input data for this method is established. We assume that the desired solution satisfies a sourcewise condition, and we use no structural conditions on the operator of the problem.