Title
Empirical Comparisons of Computer Models for Stellar Evolution
Speaker
David van Dyk, University of California, Irvine
Abstract
Color Magnitude Diagrams (CMDs) are plots that compare stellar absolute magnitudes in different colors. High non-linear correlations among the mass, color and surface temperature of newly formed stars induce a long narrow curved point cloud in a CMD known as the main sequence. Aging stars form new CMD groups of red giants and white dwarfs. The physical processes that govern this evolution are studied with complex computer models used to predict the plotted magnitudes as a function of parameters of scientific interest such as stellar age, mass and metallicity. Here, we describe how we use the computer models as complex likelihood functions in a Bayesian analysis that requires sophisticated computing, corrects for contamination of field stars in the data, accounts for complications caused by binary stars, and aims to compare competing physics-based computer models of stellar evolution. Joint work with: Steven DeGennaro, Ted von Hippel, William Jeffery, Nathan Stein, Elizabeth Jeffery
Meet the speaker in Room 212 Cockins Hall at 4:30 p.m. Refreshments will be served.
