English
Related papers

Related papers: Diffuse Ionized Gas in the Dwarf Irregular Galaxy …

200 papers

We present an HI and optical study of the gas-rich dwarf irregular galaxy DDO 88. Although DDO 88's global optical and HI parameters are normal for its morphological type, it hosts a large (3 kpc diameter) and unusually complete ring of…

Astrophysics · Physics 2009-11-10 Caroline E. Simpson , Deidre A. Hunter , Patricia M. Knezek

In this study we present high-resolution VIsible Multi-Object Spectrograph integral field unit spectroscopy (VIMOS-IFU) of the extremely metal-poor HII/blue compact dwarf (BCD) galaxy Tol 65. The optical appearance of this galaxy shows…

Astrophysics of Galaxies · Physics 2015-12-29 P. Lagos , R. Demarco , P. Papaderos , E. Telles , A. Nigoche-Netro , A. Humphrey , N. Roche , J. M. Gomes

The ionization of diffuse gas located far above the energetic midplane OB stars poses a challenge to the commonly accepted notion that radiation from OB stars is the primary ionization source for gas in galaxies. We investigated the sources…

Astrophysics of Galaxies · Physics 2024-09-25 R. P. V. Rautio , H. Salo , A. E. Watkins , S. Comerón , A. Venhola

We present the discovery of a luminous unresolved H II complex on the edge of dwarf galaxy GAMA J141103.98-003242.3 using data from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. This dwarf galaxy is situated…

We present HI spectral-line imaging of the extremely metal-poor galaxy DDO 68. This system has a nebular oxygen abundance of only 3% Z$_{\odot}$, making it one of the most metal-deficient galaxies known in the local volume. Surprisingly,…

In order to recognize environmental effects on the evolution of dwarf galaxies in clusters of galaxies, it is first necessary to quantify the properties of objects which have evolved in relative isolation. With oxygen abundance as the gauge…

We present empirical HII region oxygen abundances for a sample of low-luminosity starburst galaxies which are in a short lived evolutionary state. All five galaxies are characterized by centrally concentrated star formation, which is…

Astrophysics · Physics 2011-02-11 K. E. Dellenbusch , J. S. Gallagher , P. M. Knezek

Dwarf Galaxies are the most common objects in the Universe and are believed to contain large amounts of dark matter. There are mainly three morphologic types of dwarf galaxies: dwarf ellipticals, dwarf spheroidals and dwarf irregulars.…

Astrophysics of Galaxies · Physics 2014-11-10 V. Lora , A. C. Raga , E. K. Grebel

The apparent lack of cold molecular gas in blue compact dwarf (BCD) galaxies is at variance with their intense star-formation episode. The CO molecule, often used a tracer of H2 through a conversion function, is selectively photodissociated…

Astrophysics of Galaxies · Physics 2020-01-08 Vianney Lebouteiller

We study the neutral hydrogen distribution and kinematics in the Local Group dwarf irregular galaxy IC 1613 and compare them with the ionized gas distribution and stellar content of the galaxy. We discuss several mechanisms which may be…

A detailed spectroscopic study, from lambda 3700 A to 1 um, was performed for a sample of 34 HII galaxies in order to derive fundamental parameters for their HII regions and ionizing sources, as well as gaseous metal abundances. All the…

Astrophysics · Physics 2009-11-11 C. Kehrig , J. M. Vilchez , E. Telles , F. Cuisinier , E. Perez-Montero

A galaxy's mean metallicity is usually closely correlated with its luminosity and mass. Consequently the most metal-poor galaxies in the local universe are dwarf galaxies. Blue compact dwarfs and tidal dwarfs tend to deviate from the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Eva K. Grebel

The Draco dwarf spheroidal galaxy (dSph), with its apparent immense mass to light ratio and compact size, holds many clues to the nature of the enigmatic dark matter. Here we present deep photometric studies of this dwarf galaxy, undertaken…

Astrophysics · Physics 2008-11-26 Mathieu Segall , Rodrigo Ibata , Michael Irwin , Nicolas Martin , Scott Chapman

As part of a large study to map the distribution of star formation across galactic disks, we have obtained deep Halpha images of the nearby Sculptor Group spirals NGC 247 and NGC 7793. These images are of sufficiently high quality that they…

(Abridged) We investigate the interplay between starbursts and host galaxies by studying the structure and physical characteristics of the ionized gas surrounding the central starbursts in the two nearby galaxies NGC5253 and NGC5236. The…

Astrophysics · Physics 2009-10-31 D. Calzetti , C. J. Conselice , J. S. Gallagher , A. L. Kinney

The conversion factor from carbon monoxide (CO) intensity to molecular gas mass is a source of large uncertainty in understanding gas and its relation to star formation in galaxies. In particular, the conversion factor in low metallicity…

Astrophysics of Galaxies · Physics 2023-11-21 Shinya Komugi , Miku Inaba , Tetsuo Shindou

We use integral field spectroscopy from the PHANGS-MUSE survey, which resolves the ionised interstellar medium at ${\sim}50$ pc resolution in 19 nearby spiral galaxies, to study the origin of the diffuse ionised gas (DIG). We examine the…

A detailed kinematic analysis of ionized gas in the nearby irregular galaxy NGC 4449 is presented. Observations are conducted in the spectral lines of Halpha and [SII]. Our scanning Fabry--Perot interferometric observations are presented…

We present the results of BVRI imaging and optical spectroscopy of the dwarf galaxy A0951+68. The images reveal that, although this galaxy is classified as a dwarf elliptical, it has some properties that are similar to dwarf irregular…

Astrophysics · Physics 2015-06-24 R. A. Johnson , A. Lawrence , R. Terlevich , D. Carter

In this paper, we use the Mappings photoionization code to explore the physical parameters that impact on the measurement of electron temperature and abundance in HII regions. In the previous paper we presented observations and measurements…

Astrophysics of Galaxies · Physics 2015-06-19 David C. Nicholls , Michael A. Dopita , Ralph S. Sutherland , Helmut Jerjen , Lisa J. Kewley , Hassan Basurah