Grant: Discovery Grants Program - Individual

The proposed research focuses on two diverse yet intrinsically related areas of stellar astrophysics: (1)interacting binaries containing white dwarfs, neutron stars/pulsars and black holes; and, (2) low-mass stars, brown dwarfs, and exoplanets. While new avenues of investigation will be explored (for example, the irradiation of stars and exoplanets), we will take advantage of the significant investments that have already been made for continuing projects (e.g., a large suite of codes that have been developed to carry out numerical simulations using our HPC infrastructure). It is expected that the proposed research will have a significant impact on the areas of supernova research, CVs, LMXBs, and on the study of substellar objects and exoplanets.(1) Binary systems containing collapsed stars exhibit a rich variety of astrophysical phenomena. Interacting binaries containing accreting white dwarfs (Cataclysmic Variables [CVs]) share the same lineage as supersoft X-ray sources (SXSs) and thus could be the progenitors of Type Ia supernovae (SNe). Because Type Ia SNe are used as cosmological standard candles, they are the key tools to measure cosmological parameters thereby allowing us to infer the evolution of the universe. We will try to definitively establish the progenitors of these important cosmic distance indicators.(2) We also propose to investigate the irradiation of Jupiter-mass exoplanets by their host stars. These so-called 'Hot Jupiters' are characterized by nearly circular, close orbits (orbital periods of less than 7 days). Observational research is starting to reveal more details about the properties of these objects and we plan to model the effects of the heating on their long-term evolution. Understanding the long-term evolution of these Hot Jupiters is of central importance to understanding the dynamical evolution of planetary systems.