Misc,
Local Volume TiNy Titans: Gaseous Dwarf-Dwarf Interactions in the Local Universe
(2016)cite arxiv:1603.09342Comment: 21 pages, 10 figures, accepted for publication in MNRAS.
Abstract
In this paper, we introduce the Local Volume TiNy Titans sample (LV-TNT),
which is a part of a larger body of work on interacting dwarf galaxies: TNT
(Stierwalt et al. 2015). This LV-TNT sample consists of 10 dwarf galaxy pairs
in the Local Universe (< 30 Mpc from Milky Way), which span mass ratios of
M_(*,1)/M_(*,2) < 20, projected separations < 100 kpc, and pair member masses
of log(M_*/M_Sun) < 9.9. All 10 LV-TNT pairs have resolved synthesis maps of
their neutral hydrogen, are located in a range of environments and captured at
various interaction stages. This enables us to do a comparative study of the
diffuse gas in dwarf-dwarf interactions and disentangle the gas lost due to
interactions with halos of massive galaxies, from the gas lost due to mutual
interaction between the dwarfs. We find that the neutral gas is extended in the
interacting pairs when compared to non-paired analogs, indicating that gas is
tidally pre-processed. Additionally, we find that the environment can shape the
HI distributions in the form of trailing tails and that the gas is not unbound
and lost to the surroundings unless the dwarf pair is residing near a massive
galaxy. We conclude that a nearby, massive host galaxy is what ultimately
prevents the gas from being reaccreted. Dwarf-dwarf interactions thus represent
an important part of the baryon cycle of low mass galaxies, enabling the
"parking" of gas at large distances to serve as a continual gas supply channel
until accretion by a more massive host.
