Title: Theoretical understanding of dust evolution and extinction curves in galaxies
Speaker: Prof. Hiroyuki Hirashita (ASIAA)
Date: April 23 at 14:30
Location: R521, General Building II
Dust extinction and emission are fundamental processes in characterizing the galaxy spectral energy distributions and in interpreting multi-band galaxy survey data. However, the evolution of dust properties (especially, grain size distribution) affecting these processes has not been well understood. This also limits the understanding of observational properties of high-redshift galaxies. In this presentation, we first explain the basic dust evolution processes that determine the evolution of grain size distribution. Next we introduce our recent modeling efforts toward the understanding of grain size distribution and extinction curves. In particular, the model includes the evolution of grain size distribution and grain compositions. We also confirm that the extinction curves in nearby galaxies are fairly reproduced. The model is also successfully combined with a cosmological simulation, and is successful in reproducing the Milky Way extinction curve for Milky Way-type galaxies. Based on the above success, we discuss what our model predicts for high-redshift galaxies. Finally, we introduce our recent efforts of including more complexity, especially the grain porosity, which also affects extinction curves.