Metallic Winds in Dwarf Galaxies

Abstract

We present results from models of galactic winds driven by energy injected from nuclear (at the galactic center) and non-nuclear starbursts. The total energy of the starburst is provided by very massive young stellar clusters,which can push the galactic interstellar medium and produce an important outflow. Such outflow can be a well, or partially mixed wind, or a highly metallic wind. We have performed adiabatic 3D N-Body/Smooth Particle Hydrodynamics simulations of galactic winds using the gadget-2 code. The numerical models cover a wide range of parameters, varying the galaxy concentration index, gas fraction of the galactic disk, and radial distance of the starburst. We show that an off-center starburst in dwarf galaxies is the most effective mechanism to produce a significant loss of metals (material from the starburst itself). At the same time a non-nuclear starburst produce a high efficiency of metal loss, in spite of having a moderate to low mass loss rate.

High-resolution three-dimensional simulations of gas removal from ultrafaint dwarf galaxies

“…A recent numerical study of metal-rich winds in dwarf galaxies is the one of Robles-Valdez et al (2017), based on 3D Nbody/smoothed particle hydrodynamics. The study focuses the attention on important parameters such as the galaxy concentration index, the gas fraction and the shape of the mass distribution, as well as the position of the starburst inside the system.…”

The Role of Stellar Feedback in the Chemical Evolution of a Low Mass Dwarf Galaxy

“…Revaz et al 2016;Su et al 2018;Applebaum et al 2020); the role of various forms of feedback in driving metal-rich galactic winds and dwarf galaxy self-quenching (e.g. Mac Low & Ferrara 1999;Recchi & Hensler 2013;Caproni et al 2017;Robles-Valdez et al 2017), with recent focus particularly on the lowest mass dwarf galaxies (e.g. Bland-Hawthorn et al 2015;Cashmore et al 2017;Romano et al 2019); the role of photoelectric (PE) heating in concert with other mechanisms for stellar feedback in regulating star formation and the warm, neutral ISM in dwarf galaxies (Forbes et al 2016;Hu et al 2016Hu et al , 2017; the importance of ionizing radiation and radiation pressure in driving dwarf galaxy evolution (e.g.…”

Chemical and stellar properties of star-forming dwarf galaxies

“…More successful chemical evolution models of SFDs have invoked both infall and winds to reproduce the observed low chemical abundances [e.g., 8, 122, 160-162], suggesting that the outflows triggered by supernova explosions in these shallow potential well systems may be very efficient in ejecting some of the elements (like oxygen) out of the system. Hydrodynamical simulations of dwarf galaxies [163][164][165][166][167] have shown indeed that the winds blowing out of these galaxies can remove substantial amounts of the elements produced by the supernovae themselves, without removing much of the overall gas content; on the other hand, feedback from active galactic nuclei (AGN) has started to be included in models of dwarf galaxy evolution since only very recently [e.g. , 168].…”