Results 1 to 10 of about 11,751 (112)

Giant Halos in Dwarf Irregular Galaxies vs. Dwarf Elliptical Galaxies [PDF]

Proceedings of the International Astronomical Union, 2005
We present a discovery of a giant stellar halo in NGC 6822, a dwarf irregular galaxy in the Local Group. This halo is mostly made of old red giants, showing striking features: 1) it is several times larger than the main body of the galaxy seen in the ...
Hwang, Narae, Lee, Myung Gyoon
core   +2 more sources

Lopsidedness in dwarf irregular galaxies [PDF]

Monthly Notices of the Royal Astronomical Society, 2000
We quantify the amplitude of the lopsidedness, the azimuthal angular asymmetry index, and the concentration of star forming regions, as represented by the distribution of the H$\alpha$ emission, in a sample of 78 late-type irregular galaxies.
Abraham, Alexander, Almoznino, Ana B. Heller, Brosch, Carignan, Conselice, Dohm-Palmer, Dohm-Palmer, Dohm-Palmer, Draper, Edelson, Elchanan Almoznino, Elmegreen, Gerola, Heller, Heller, Hunter, Jog, John J. Salzer, Kaspi, Kornreich, Larson, Leitherer, Levine, Liese van Zee, Mihos, Moffat, Netzer, Noah Brosch, Rudnick, Salzer, Schechter, Skillman, van Zee, van Zee, van Zee, van Zee, van Zee, Walker, Young, Zaritsky   +41 more
core   +5 more sources

The intrinsic shapes of dwarf irregular galaxies [PDF]

Monthly Notices of the Royal Astronomical Society: Letters, 2013
Abstract We use the measured B-band axial ratios of galaxies from an updated catalogue of Local Volume galaxies to determine the intrinsic shape of dwarf irregular galaxies (de Vaucouleurs’ morphological types 8–10). We find that the shapes change systematically with luminosity, with fainter galaxies being thicker.
Sambit Roychowdhury, Jayaram N Chengalur, Igor D Karachentsev   +2 more
exaly   +4 more sources

Redshift, metallicity and size of two extended dwarf Irregular galaxies. A link between dwarf Irregulars and ultra diffuse galaxies? [PDF]

Monthly Notices of the Royal Astronomical Society, 2017
We present the results of the spectroscopic and photometric follow-up of two field galaxies that were selected as possible stellar counterparts of local high velocity clouds. Our analysis shows that the two systems are distant (D>20 Mpc) dwarf irregular galaxies unrelated to the local HI clouds.
M Bellazzini, Vasily Belokurov, L Magrini   +2 more
exaly   +5 more sources

Star Formation in Sculptor Group Dwarf Irregular Galaxies and the Nature of "Transition" Galaxies [PDF]

The Astronomical Journal, 2002
We present new H-alpha narrow band imaging of the HII regions in eight Sculptor Group dwarf irregular (dI) galaxies. Comparing the Sculptor Group dIs to the Local Group dIs, we find that the Sculptor Group dIs have, on average, lower values of SFR when ...
Babul A., Binggeli B., Bomans D. J., Brosch N., Bryan W. Miller, Efstathiou G., Evan D. Skillman, Heisler C. A., Quinn T., Scalo J. M., Stéphanie Côté   +10 more
core   +3 more sources

Chemical evolution of dwarf irregular and blue compact galaxies [PDF]

Astronomy and Astrophysics, 2011
Dwarf irregular and blue compact galaxies are very interesting objects since they are relatively simple and unevolved. We present new models for the chemical evolution of these galaxies by assuming different regimes of star formation (bursting and continuous) and different kinds of galactic winds (normal and metal-enhanced).
F Matteucci
exaly   +4 more sources

First Stellar Abundances in the Dwarf Irregular Galaxy Sextans A [PDF]

The Astronomical Journal, 2004
We present the abundance analyses of three isolated A-type supergiant stars in the dwarf irregular galaxy Sextans A from high-resolution spectra the UVES spectrograph at the VLT.
Andreas Kaufer, Ballester P., Christophe Pinte, Edvardsson B., Eline Tolstoy, Gigas D., Gigas D., Gummersbach C. A., Huchtmeier W. K., Kaufer A., Kaufer A., Kim A. Venn, Korn A. J., Kurucz R. L., Matteuchi F., Matteuchi F., Nissen P. E., Przybilla N., Rentzsch-Holm I., Rolf-Peter Kudritzki, Rolleston W. R. J., Skillman E. D., Tomita A.   +22 more
core   +4 more sources

Thick gas discs in faint dwarf galaxies

Monthly Notices of the Royal Astronomical Society: Letters, 2010
We determine the intrinsic axial ratio distribution of the 'gas' disks of extremely faint M_B > -14.5 dwarf irregular galaxies. We start with the measured (beam corrected) distribution of apparent axial ratios in the HI 21cm images of dwarf irregular ...
Sambit Roychowdhury, Jayaram N Chengalur, Ayesha Begum   +2 more
exaly   +3 more sources

The CO content of the Local Group dwarf irregular galaxies IC 5152, UGCA 438 and the Phoenix dwarf [PDF]

Monthly Notices of the Royal Astronomical Society, 2006
We present a search for CO(1->0) emission in three Local Group dwarf irregular galaxies: IC5152, the Phoenix dwarf, and UGCA438, using the ATNF Mopra radio telescope.
D Michielsen, Jürgen Ott, H Dejonghe
exaly   +4 more sources

The Interstellar Medium in Dwarf Irregular Galaxies

Annual Review of Astronomy and Astrophysics
Dwarf irregular (dIrr) galaxies are among the most common type of galaxy in the Universe. They typically have gas-rich, low-surface-brightness, metal-poor, and relatively thick disks. Here, we summarize the current state of our knowledge of the interstellar medium (ISM), including atomic, molecular, and ionized gas, along with ...
Deidre A Hunter, Bruce G Elmegreen, S C Madden   +2 more
exaly   +4 more sources