scholarly journals A kinematic study of the neutral and ionized gas in the irregular dwarf galaxies IC 4662 and NGC 5408★

2010 ◽  
Vol 407 (1) ◽  
pp. 113-132 ◽  
Author(s):  
Janine Van Eymeren ◽  
Bärbel S. Koribalski ◽  
Ángel R. López-Sánchez ◽  
Ralf-Jürgen Dettmar ◽  
Dominik J. Bomans
Keyword(s):  
Dwarf Galaxies ◽  
Ionized Gas ◽  
Kinematic Study

scholarly journals The Interstellar Medium of Dwarf Galaxies

Galaxies ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 11
Author(s):  
Christian Henkel ◽  
Leslie K. Hunt ◽  
Yuri I. Izotov
Keyword(s):  
Interstellar Medium ◽  
Dwarf Galaxies ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Ionized Gas ◽  
Green Pea ◽  
Physical And Chemical ◽  
The Impact ◽  
The Universe ◽  
And Chemical Properties

Dwarf galaxies are by far the most numerous galaxies in the Universe, showing properties that are quite different from those of their larger and more luminous cousins. This review focuses on the physical and chemical properties of the interstellar medium of those dwarfs that are known to host significant amounts of gas and dust. The neutral and ionized gas components and the impact of the dust will be discussed, as well as first indications for the existence of active nuclei in these sources. Cosmological implications are also addressed, considering the primordial helium abundance and the similarity of local Green Pea galaxies with young, sometimes protogalactic sources in the early Universe.

scholarly journals Hα Kinematics of Tidal Tails in Interacting Systems: Projection Effects and Dark Matter in TDGs

2004 ◽  
Vol 217 ◽  
pp. 526-531
Author(s):  
Philippe Amram ◽  
Fréderic Bournaud ◽  
Pierre-Alain Duc
Keyword(s):  
Dark Matter ◽  
Dwarf Galaxies ◽  
Matter Content ◽  
Field Of View ◽  
Large Field ◽  
Ionized Gas ◽  
Tidal Tail ◽  
Fabry Perot ◽  
Interacting Systems ◽  
Tidal Tails

Several interacting systems exhibit at the tip of their long tidal tails massive condensations of atomic hydrogen, which may be the progenitors of Tidal Dwarf Galaxies. Because, quite often, these tails are observed edge-on, projection effects have been claimed to account for the large HI column densities measured there. Here we show that determining the velocity field all along the tidal features, one may disentangle projection effects along the line of view from real bound structures. Due to its large field of view, high spectral and 2D spatial resolutions, Fabry-Perot observations of the ionized gas are well adapted to detect a kinematical signature of either streaming motions along a bent tidal tail or of in-falling/rotating material associated with a forming TDG. Spectroscopic observations also allow to measure the dynamical masses of the TDGs that are already relaxed and check their dark matter content.

Photometric Studies of Very Metal-Deficient Blue Compact Dwarf Galaxies: The Exponential Ionized Gas Halo of I Zw18

2003 ◽  
pp. 325-328
Author(s):  
P. Papaderos ◽  
Y. I. Izotov ◽  
K. G. Noeske ◽  
L. M. Cairós ◽  
N. G. Guseva ◽  
...  
Keyword(s):  
Dwarf Galaxies ◽  
Ionized Gas

scholarly journals On the Nature of Dwarf Galaxies in the Interacting Group HCG 31

2004 ◽  
Vol 217 ◽  
pp. 568-569
Author(s):  
Ángel R. López-Sánchez ◽  
César Esteban ◽  
Mónica Rodríguez
Keyword(s):  
Chemical Composition ◽  
Compact Group ◽  
Dwarf Galaxies ◽  
Ionized Gas ◽  
Origin And Evolution ◽  
Global View

We have analysed the morphology, kinematics, colors and chemical composition of the ionized gas of the different objects belonging to the interacting compact group HCG 31 in order to get a global view of the origin and evolution of the dwarf galaxies present in it.

scholarly journals Ionized gas in dwarf galaxies: Abundance indicators

2008 ◽  
Vol 4 (S255) ◽  
pp. 375-380 ◽  
Author(s):  
Grażyna Stasińska
Keyword(s):  
Chemical Composition ◽  
Unsolved Problem ◽  
Dwarf Galaxies ◽  
Temperature Fluctuations ◽  
Hii Regions ◽  
Ionized Gas ◽  
Hii Region

AbstractWe discuss the four basic methods to derive HII region abundances in metal-poor galaxies by presenting a few recent results obtained with these methods. We end up by commenting on the yet unsolved problem of temperature fluctuations in HII regions, which may plague abundance determinations, as well as the discrepancy between abundances derived from recombination lines and collisionally excited lines, to which inhomogeneous chemical composition might be the explanation.

scholarly journals How does metallicity affect the gas and dust properties of galaxies?

2015 ◽  
Vol 11 (S315) ◽  
pp. 191-198 ◽  
Author(s):  
Suzanne C. Madden ◽  
Diane Cormier ◽  
Aurélie Rémy-Ruyer
Keyword(s):  
Star Formation ◽  
Molecular Clouds ◽  
Dwarf Galaxies ◽  
Molecular Gas ◽  
Ionized Gas ◽  
Active Star ◽  
Multiphase Structure ◽  
Wide Range ◽  
Self Consistent ◽  
Low Metallicity

AbstractComparison of the ISM properties of a wide range of metal poor galaxies with normal metal-rich galaxies reveals striking differences. We find that the combination of the low dust abundance and the active star formation results in a very porous ISM filled with hard photons, heating the dust in dwarf galaxies to overall higher temperatures than their metal-rich counterparts. This results in photodissociation of molecular clouds to greater depths, leaving relatively large PDR envelopes and difficult-to-detect CO cores. From detailed modeling of the low-metallicity ISM, we find significant fractions of CO-dark H2 - a reservoir of molecular gas not traced by CO, but present in the [CII] and [CI]-emitting envelopes. Self-consistent analyses of the neutral and ionized gas diagnostics along with the dust SED is the necessary way forward in uncovering the multiphase structure of galaxies.

Sign in / Sign up

Export Citation Format

Share Document