Evolutionary calculations for planetary nebula nuclei with continuing mass loss and realistic starting conditions

This paper describes evolutionary calculations for nuclei of planetary nebulae (NPN) which have been made using a variety of assumptions regarding (1) mass of the NPN, (2) phase in the He shell flash cycle at which the NPN leaves the asymptotic giant branch, and (3) time variation of the mass loss rate. It is hoped that the comparison of these calculations with sufficiently precise observations, when these are available, will resolve some of the present uncertainties regarding planetary shell ejection.