Dust-regulated galaxy formation and evolution:A new chemodynamical model with live dust particles

TL;DR

This paper introduces a novel chemodynamical model with live dust particles that self-consistently simulates the influence of dust on galaxy formation and evolution, highlighting the importance of dust-driven processes like radiation pressure and H_2 formation.

Contribution

The model uniquely represents different dust species as live particles that interact gravitationally and undergo physical processes, advancing the simulation of dust's role in galaxy evolution.

Findings

Dust distribution evolution affects star formation rates.

Radiation pressure influences gas and dust dynamics.

Dust processes impact chemical abundances and H_2 fractions.

Abstract

Interstellar dust plays decisive roles in the conversion of neutral to molecular hydrogen (H_2), the thermodynamical evolution of interstellar medium (ISM), and the modification of spectral energy distributions (SEDs) of galaxies. These important roles of dust have not been self-consistently included in previous numerical simulations of galaxy formation and evolution. We have therefore developed a new model by which one can investigate whether and how galaxy formation and evolution can be influenced by dust-related physical processes such as photo-electric heating, H_2 formation on dust, and stellar radiation pressure on dust in detail. A novel point of the model is that different dust species in a galaxy are represented by `live dust' particles (i.e., not test particles). Therefore, dust particles in a galaxy not only interact gravitationally with all four components of the galaxy (i.e., dark matter, stars, gas, and dust) but also are grown and destroyed through physical processes of ISM. First we describe a way to include dust-related physical processes in Nbody+hydrodynamical simulations of galaxy evolution in detail. Then we show some preliminary results of dust-regulated galaxy evolution. The preliminary results suggest that the evolution of dust distributions driven by radiation pressure of stars is very important for the evolution of star formation rates, chemical abundances, H_2 fractions, and gas distributions in galaxies.