Place: 4421 Sterling Hall, Coffee and cookies 3:15, Talk at 3:30 PM
Speaker: Thiem Hoang, CITA
Abstract: We are entering a golden age of dust polarimetry with numerous CMB experiments (e.g., SPIDER, BICEP/Keck, LiteBIRD) hunting for primordial gravitational waves through B-mode polarization, and a dozen of big instruments designed to elucidate the roles of magnetic fields in star formation through submm/mm polarization (e.g., SOFIA, SMA, ALMA). The correct determination of B-mode signal, as well as reliable understanding of magnetic fields in star formation, are only achieved when we have a quantitative treatment of dust polarization. In this talk, first, I will present our recent works on quantifying the polarization of spinning dust emission and magnetic dust emission. Second, I will present our quantitative theory of grain alignment, physical modeling of dust polarization with our theory, and comparisons with observational data. Then, I will discuss our ongoing efforts to construct an accurate physical modeling of dust polarization needed for reliable component separation in cosmic microwave background polarization experiments. Finally, I will discuss our numerical simulations of dust polarization in molecular clouds, which will shed light on the roles of magnetic fields in star formation.