Ionized gas velocity dispersion in nearby dwarf galaxies: looking at supersonic turbulent motions★

AbstractWe present recent results showing that a large fraction of red sequence galaxies contain ionized gas with LINER-like optical emission line ratios. This emission is more frequently found in galaxies with lower central velocity dispersion (σ) and these galaxies typically have younger mean ages than galaxies at the same σ which do not host emission. We suggest that the presence of LINER-like emission may be determined by the quantity of interstellar material in these galaxies and may be associated with the recent accretion of a gas-rich satellite galaxy or alternatively with stellar mass loss that declines as the galaxy stellar population ages.

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The MURALES survey

Astronomy and Astrophysics ◽

10.1051/0004-6361/202039062 ◽

2020 ◽

Vol 645 ◽

pp. A12

Author(s):

B. Balmaverde ◽

A. Capetti ◽

A. Marconi ◽

G. Venturi ◽

M. Chiaberge ◽

...

Keyword(s):

Emission Line ◽

Large Scale ◽

Line Emission ◽

Emission Region ◽

Gas Velocity ◽

Ionized Gas ◽

Large Scale Structures ◽

Scale Structures ◽

Integral Field Spectrograph ◽

Integral Field

We present the final observations of a complete sample of 37 radio galaxies from the Third Cambridge Catalogue (3C) with redshift < 0.3 and declination < 20° obtained with the VLT/MUSE optical integral field spectrograph. These data were obtained as part of the MUse RAdio Loud Emission line Snapshot (MURALES) survey with the main goal of exploring the AGN feedback process in the most powerful radio sources. We present the data analysis and, for each source, the resulting emission line images and the 2D gas velocity field. Thanks to the unprecedented depth these observations reveal emission line regions (ELRs) extending several tens of kiloparsec in most objects. The gas velocity shows ordered rotation in 25 galaxies, but in several sources it is highly complex. We find that the 3C sources show a connection between radio morphology and emission line properties. In the ten FR I sources the line emission region is generally compact, only a few kpc in size; only in one case does it exceed the size of the host. Conversely, all but two of the FR II galaxies show large-scale structures of ionized gas. The median extent is 16 kpc with the maximum reaching a size of ∼80 kpc. There are no apparent differences in extent or strength between the ELR properties of the FR II sources of high and low gas excitation. We confirm that the previous optical identification of 3C 258 is incorrect: this radio source is likely associated with a quasi-stellar object at z ∼ 1.54.

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The Interstellar Medium of Dwarf Galaxies

Galaxies ◽

10.3390/galaxies10010011 ◽

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.

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MaNGA galaxies with off-centered spots of enhanced gas velocity dispersion

Astronomy and Astrophysics ◽

10.1051/0004-6361/202141012 ◽

2021 ◽

Author(s):

L. S. Pilyugin ◽

B. Cedres ◽

I. A. Zinchenko ◽

A. M. Perez Garcia ◽

M. A. Lara-Lopez ◽

...

Keyword(s):

Velocity Dispersion ◽

Gas Velocity

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

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2010.16923.x ◽

2010 ◽

Vol 407 (1) ◽

pp. 113-132 ◽

Cited By ~ 20

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

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Minibars in the Centers of Normal Galaxies

International Astronomical Union Colloquium ◽

10.1017/s0252921100049733 ◽

1996 ◽

Vol 157 ◽

pp. 207-211

Author(s):

A. V. Zasov ◽

O. K. Sil’chenko

Keyword(s):

High Frequency ◽

Spiral Galaxies ◽

Velocity Fields ◽

Frequency Of Occurrence ◽

Gas Velocity ◽

Ionized Gas ◽

Normal Galaxies ◽

Normal Spiral

AbstractAnalysis of ionized gas velocity fields in the circumnuclear regions of 13 normal spiral galaxies has shown that about half of them reveal a discrepancy between the kinematical axis at R < 2″ and the photometric or kinematical axes of the outer regions. This result indicates a high frequency of occurrence of non-axisymmetric gravitational potentials in the inner few hundred parsecs of galaxies. The possible nature of these minibars is discussed.

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WARM IONIZED GAS REVEALED IN THE MAGELLANIC BRIDGE TIDAL REMNANT: CONSTRAINING THE BARYON CONTENT AND THE ESCAPING IONIZING PHOTONS AROUND DWARF GALAXIES

The Astrophysical Journal ◽

10.1088/0004-637x/771/2/132 ◽

2013 ◽

Vol 771 (2) ◽

pp. 132 ◽

Cited By ~ 26

Author(s):

K. A. Barger ◽

L. M. Haffner ◽

J. Bland-Hawthorn

Keyword(s):

Dwarf Galaxies ◽

Ionized Gas

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MUSE-AO view of the starburst–AGN connection: NGC 7130

Astronomy and Astrophysics ◽

10.1051/0004-6361/201834669 ◽

2019 ◽

Vol 621 ◽

pp. L5 ◽

Cited By ~ 1

Author(s):

J. H. Knapen ◽

S. Comerón ◽

M. K. Seidel

Keyword(s):

Adaptive Optics ◽

Spatial Resolution ◽

Field Data ◽

Velocity Dispersion ◽

Field Of View ◽

Host Galaxy ◽

Gas Velocity ◽

Star Forming ◽

Optical Wavelengths ◽

Integral Field

We present the discovery of a small kinematically decoupled core of 0.″2 (60 pc) in radius as well as an outflow jet in the archetypical AGN–starburst “composite” galaxy NGC 7130 from integral field data obtained with the adaptive optics-assisted MUSE-NFM instrument on the VLT. Correcting the already good natural seeing at the time of our science verification observations with the four-laser GALACSI AO system, we reach an unprecedented spatial resolution at optical wavelengths of around 0.″15. We confirm the existence of star-forming knots arranged in a ring of 0.″58 (185 pc) in radius around the nucleus, previously observed from UV and optical Hubble Space Telescope and CO(6-5) ALMA imaging. We determine the position of the nucleus as the location of a peak in gas velocity dispersion. A plume of material extends towards the NE from the nucleus until at least the edge of our field of view at 2″ (640 pc) radius which we interpret as an outflow jet originating in the AGN. The plume is not visible morphologically, but is clearly characterised in our data by emission-line ratios characteristic of AGN emission, enhanced gas velocity dispersion, and distinct non-circular gas velocities. Its orientation is roughly perpendicular to the line of nodes of the rotating host galaxy disc. A circumnuclear area of positive and negative velocities of 0.″2 in radius indicates a tiny inner disc, which can only be seen after combining the integral field spectroscopic capabilities of MUSE with adaptive optics.

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