Unlocking the Potential of Speckle Binary Stars for Stellar and Galactic Astronomy

University Of Massachusetts, Dartmouth, North Dartmouth MA

Investigators

Abstract

AST 0307450 Horch, Elliott P. Knowledge of the distances to stars is about to experience an unprecedented improvement due to planned space-based missions. These missions present broad opportunities to gain a better understanding of stellar astrophysics. Close binary stars will play a significant role here. To aid in the realization of this science, a systematic program of ground-based photometric, astrometric, and spectroscopic observations is underway. Reliable magnitude differences in multiple colors produce accurate component luminosities and effective temperatures and is now being done by speckle photometry. Complete spectroscopic information provides radial velocities for conversion into mass fractions, and therefore individual masses when combined with the visual orbit. This research enables robust comparisons between the observations and stellar evolution models and important statistical studies, such as a study of the chemical evolution of this region of the galaxy. The observational data will lead to a much improved mass-luminosity relation, including the ability to study such effects as metallicity and age, and it will provide a list of astrophysically interesting binaries for future observations. Broader Impacts. Noted astronomers are being brought to the University of Massachusetts, Dartmouth in the Southeastern Massachusetts region for public lectures, and an elementary astrophysics course is being made available in an online learning version. A second new course in imaging will benefit science and engineering majors at the University and have a cross- disciplinary aspect desirable to their future employers.