Efficiency of metal mixing in dwarf galaxies
  Metal mixing plays critical roles in the enrichment of metals in galaxies.
The abundance of elements such as Mg, Fe, and Ba in metal-poor stars help us
understand the metal mixing in galaxies. However, the efficiency of metal
mixing in galaxies is not yet understood. Here we report a series of
$N$-body/smoothed particle hydrodynamics simulations of dwarf galaxies with
different efficiencies of metal mixing using turbulence-induced mixing model.
We show that metal mixing apparently occurs in dwarf galaxies from Mg and Ba
abundance. We find that the scaling factor for metal diffusion larger than 0.01
is necessary to reproduce the observation of Ba abundance in dwarf galaxies.
This value is consistent with the value expected from turbulence theory and
experiment. We also find that timescale of metal mixing is less than 40 Myr.
This timescale is shorter than that of typical dynamical times of dwarf
galaxies. We demonstrate that the determination of a degree of scatters of Ba
abundance by the observation will help us to constrain the efficiency of metal
mixing more precisely.
