2017/03/16 by Yutaka Hirai, Takayuki R. Saitoh · 34 citations
Physics and Astronomy · #Abundance (ecology) #Astronomy and Astrophysical Research #Dwarf galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Metal #Metallicity #Mixing (physics) #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR #physics.flu-dyn
paper · pdf · doi:10.3847/2041-8213/aa6799
published in The Astrophysical Journal Letters 838(2), L23 (IOP Publishing) · 7 pages, 2 figures, accepted for publication in ApJL
arxiv created 2017/03/16 · openalex publication_date 2017/04/01 · openalex created_date 2017/04/07 · arxiv updated 2017/04/12 · openalex updated_date 2026/08/05
Abstract Metal mixing plays a critical role in the enrichment of metals in galaxies. The abundance of elements such as Mg, Fe, and Ba in metal-poor stars helps 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 a turbulence-induced mixing model. We show that metal mixing apparently occurs in dwarf galaxies from Mg and Ba abundances. We find that a scaling factor for metal diffusion larger than 0.01 is necessary to reproduce the measured abundances of Ba in dwarf galaxies. This value is consistent with the value expected from turbulence theory and experiments. We also find that the timescale of metal mixing is less than 40 Myr. This timescale is shorter than the 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 better constrain the efficiency of metal mixing.