NSF Award
1413660
Over billions of years, stars similar to our sun evolve to form red giants that eventually eject their outer shells, forming planetary nebulae (PNe). Planetary nebulae play an important role in the chemical evolution of the galaxy by returning material created within stars to create brand-new stars. The transition from red giant to planetary nebula is an important but relatively short-lived stage of stellar evolution, lasting only a few hundred thousand years. The goal of this proposal is to study the basic physical properties of objects in this transition phase that are referred to as proto-planetary nebulae (PPNe). This project will use a variety of observations and techniques to carry out this study. <br/><br/>PPNe represent intermediate mass objects in the late stages of stellar evolution that are transitioning from Asymptotic Giant Branch (AGB) stars to PNe. The proposal will continue and extend an existing program of photometric and radial velocity measurements of post-AGB stars and PPNe within our own galaxy and in the nearby Large and Small Magellanic Cloud galaxies. The combination of photometric light curves, color measurements, and radial velocities will permit the direct determination of fundamental parameters like stellar radius and luminosity. In addition, stellar pulsation models will be used to constrain the mass and luminosity of the PPNe. Finally, the program will investigate the degree of binarity in PPNe and its effect on the shaping of PNe.<br/><br/>This Research in Undergraduate Institutions (RUI) project will provide numerous and wide-ranging opportunities for the training of new scientists, the education of liberal arts students, and the science infrastructure at the PI's institution. The project will communicate its results to the public through open houses held at the observatory on the campus of the PI's home institution. The PI will continue to give community and professional lectures and will incorporate the results of the research into those presentations.
