V-cycle convergence of some multigrid methods for ill-posed problems

For ill-posed linear operator equations we consider some V-cycle multigrid approaches, that, in the framework of Bramble, Pasciak, Wang, and Xu (1991), we prove to yield level independent contraction factor estimates. Consequently, we can incorporate these multigrid operators in a full multigrid method, that, together with a discrepancy principle, is shown to act as an iterative regularization method for the underlying in finite-dimensional ill-posed problem. Numerical experiments illustrate the theoretical results.