The evolution of red supergiant stars to white dwarfs through the "planetary nebula nucleus" (PPN) stage occurs very quickly and is therefore one of the most poorly understood stages of stellar evolution. It is also a very important stage. It is during this time that a star returns many of the intermediate-weight elements (such as carbon, nitrogen, and oxygen) into interstellar space, from which new generations of stars are eventually formed once again. The PI proposes a program first, to identify new PPN candidates and, second, to determine their spectral energy distributions. This information will be used ultimately to infer the distribution of ages and thereby to do a sensitve "census" of their properties as they evolve through this brief phase. This study requires a great deal of data analysis and reduction, preferably on a dedicated computer. This award will support the purchase of a workstation to perform these tasks.
