Oral Presentation
Dust evolution in high-redshift galaxies: modeling toward ALMA
Presenter: Hiroyuki Hirashita (ASIAA)
We consider how ALMA is used to constrain the dust enrichment
processes in high redshift (especially, z > 6) galaxies. We
target "representative" populations such as Lyman break galaxies
and Lyman-alpha emitters. Although ALMA is very sensitive, it has
failed to detect dust continuum for most of those sources. Using
our theoretical models of dust enrichment, we constrain dust
formation by supernovae and dust growth in the dense interstellar
medium. The lack of ALMA detection mentioned above is interpreted
as a natural consequence of less efficient dust growth than in
nearby galaxies most probably because of low metallicities. We
also succeed in putting a strong constraint on the dust formation
efficiency in supernovae, and find that the constraint favors
significant dust destruction by reverse shocks in supernovae.
We also introduce our ongoing efforts of numerical simulations,
based on which we will be able to predict dust emission
properties to be directly compared with ALMA observations for both
nearby and distant galaxies.
asiaa.sinica.edu.tw