2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/11174In one dimension, we present results from comparisons of stationary state multigroup flux-limited diffusion and Boltzmann neutrino transport, focusing on quantities central to the postbounce shock reheating. In two dimensions, we present results from simulations that couple one-dimensional multigroup flux-limited diffusion to two-dimensional PPM hydrodynamics.Latex, using sprocl.sty, 3 pages, To appear in the proceedings of the 18th Texas Symposium on Relativistic AstrophysicsAstrophysicstext