Abstract
We analyze late-time observations, available photometry and spectra, of a sample of type II plateau supernovae (SNe IIP). The possibility of using Halpha luminosity at the nebular epoch as a tracer of Ni-56 mass in this class of objects is investigated, yielding a consistency with the photometry-based estimates within 20%. Interesting correlations are found and their impacts on our present understanding of the physics of core collapse SNe are discussed.