@TechReport{	  it:2019-011,
  author	= {Pietro Benedusi and Paola Ferrari and Carlo Garoni and
		  Rolf Krause and Stefano Serra-Capizzano},
  title		= {Fast Parallel Solver for the Space-Time {IgA-DG}
		  Discretization of the Anisotropic Diffusion Equation},
  institution	= {Department of Information Technology, Uppsala University},
  department	= {Division of Scientific Computing},
  year		= {2019},
  number	= {2019-011},
  month		= nov,
  abstract	= {We consider the space-time discretization of the (linear)
		  anisotropic diffusion equation, using an isogeometric
		  analysis (IgA) approximation in space and a discontinuous
		  Galerkin (DG) approximation in time. Drawing inspiration
		  from a former spectral analysis, we propose for the
		  resulting space-time linear system a new solution method
		  combining a suitable preconditioned GMRES (PGMRES)
		  algorithm with a few iterations of an appropriate multigrid
		  method. The performance of our new solution method is
		  illustrated through numerical experiments, which show its
		  competitiveness in terms of robustness, run-time and
		  parallel scaling.}
}