Dwarf Galaxies of the Local Group

Mateo, Mario

doi:10.1146/annurev.astro.36.1.435

Cited by 2,200 publications

(3,534 citation statements)

References 402 publications

Supporting

220

Mentioning

3,284

Contrasting

Unclassified

Order By: Relevance

“…To get the radial velocity map of our observed field, we found the central velocity in the radial velocity profile of each pixel, that has a level above 2 σ the value of the standard background emission, to ensure galaxy membership. (Mateo 1998). The most active region of IC 1613 is located 3 (or 663 pc) North-East from the photometric center.…”

Section: Observations and Data Reductionmentioning

confidence: 99%

Kinematics of the ionized gas in the Local Group irregular galaxy IC 1613

Valdez-Gutiérrez

Rosado

Георгиев

et al. 2001

A&A

View full text Add to dashboard Cite

Abstract. We present Hα and [S ii] observations for the Local Group irregular galaxy IC 1613 using the PUMA scanning Fabry-Perot interferometer. Our goal is to analyze the kinematics of the ionized gas in the complex sample of superbubbles located in the whole extension of our field (10 ), which includes most of the optical emission of this galaxy, and to study the inter-relationship between young stellar associations and nebulae based on a previous study that we have made on the stellar associations of the central region of this galaxy. The ionized gas in this galaxy is distributed in classical H ii regions and in a series of superbubbles (also called giant shells) covering a large fraction of the optical extent of the galaxy. We present a catalog of kinematical properties of both the H ii regions of this galaxy and the superbubbles. We have also compared the kinematics of the ionized gas in H ii regions to search for possible dynamic differences between neutral and ionized gas.

show abstract

Section: Observations and Data Reductionmentioning

confidence: 99%

Kinematics of the ionized gas in the Local Group irregular galaxy IC 1613

Valdez-Gutiérrez

Rosado

Георгиев

et al. 2001

A&A

View full text Add to dashboard Cite

show abstract

“…27) at a distance of ∼1 Mpc from the Milky Way. About thirty luminous satellite galaxies detected within the Milky Way virial radius (∼ 250 kpc) are considered possible cases of cold dark matter substructure, albeit at a much lower abundance than is predicted from simulations 15 .…”

mentioning

confidence: 99%

Gravitational detection of a low-mass dark satellite galaxy at cosmological distance

Vegetti

Lagattuta

McKean

et al. 2012

Nature

363

392

View full text Add to dashboard Cite

The mass-function of dwarf satellite galaxies that are observed around Local Group galaxies substantially differs from simulations 1-5 based on cold dark matter: the simulations predict many more dwarf galaxies than are seen. The Local Group, however, may be anomalous in this regard 6, 7 . A massive dark satellite in an early-type lens galaxy at z = 0.222 was recently found 8 using a new method based on gravitational lensing 9, 10 , suggesting that the mass fraction contained in substructure could be higher than is predicted from simulations. The lack of very low mass detections, however, prohibited any constraint on their mass function. Here we report the presence of a 1.9 ± 0.1 × 10 8 M ⊙ dark satellite in the Einstein-ring system JVAS B1938+666 (ref. 11) at z = 0.881, where M ⊙ denotes solar mass. This satellite galaxy has a mass similar to the Sagittarius 12 galaxy, which is a satellite of the Milky Way. We determine the logarithmic slope of the mass function for substructure beyond the local Universe to be α = 1.1 +0.6 −0.4 , with an average mass-fraction of f = 3.3 +3.6 −1.8 %, by combining data on both of these recently discovered galaxies. Our results are consistent with the predictions from cold dark matter simulations 13-15 at the 95 per cent confidence level,and therefore agree with the view that galaxies formed hierarchically in a Universe composed of cold dark matter.The gravitational lens system JVAS B1938+666 (ref. 11) has a bright infrared background galaxy at redshift 2.059 (ref. 16), which is gravitationally lensed into an almost complete Einstein ring of diameter ∼ 0.9 arcseconds by a massive elliptical galaxy at redshift 0. 881 (ref. 17). The bright, highly-magnified Einstein ring made this system an excellent candidate in which to to search for surface brightness anomalies caused by very low mass (dark matter) substructure in the halo around the high redshift elliptical lens galaxy. The presence of a low-mass substructure (e.g. a luminous or dark satellite galaxy; also denoted as substructure hereafter) in the lens galaxy 1

show abstract

“…Spirals near the center of the Virgo cluster are deficient in H I gas (Cayette et al 1990(Cayette et al , 1994Chung et al 2009). Also, ; ; Kormendy (1987), van den Bergh (1994b), and Kormendy et al (2009, hereafter KFCB) suggested that Sph galaxies are ram-pressure-stripped dS+Im galaxies, based in part on observations (Einasto et al 1974;van den Bergh 1994avan den Bergh , 1994bMateo 1998) that -with a few (understandable) exceptions -close dwarf companions of Local Group giant galaxies are almost all spheroidals, that distant companions are irregulars, and that galaxies with intermediate (Sph/Im) morphologies live at intermediate distances. Ever since van den Bergh (1976), these ideas provided the interpretation of a parallel sequence classification (Figure 1 here) that was constructed operationally to encode the full range of S0+Sph bulge-to-total luminosity ratios B/T from almost 1 to exactly 0.…”

Section: Environmental Processes Imentioning

confidence: 99%

Structure and Evolution of Dwarf Galaxies

Kormendy

2014

Lessons From the Local Group

View full text Add to dashboard Cite

Abstract. Different structural parameter correlations show how classical bulge components and elliptical galaxies are different from spiral and S0 galaxy disks, irregular (Im) galaxies, and spheroidal (Sph) galaxies. In contrast, the latter, apparently diverse galaxies or galaxy components have almost identical parameter correlations. This shows that they are related. A review of galaxy transformation processes suggests that S0 and spheroidal galaxies are star-formation-quenched, "red and dead" versions of spiral and Im galaxies. In particular, Sph galaxies are bulgeless S0s. This motivates a parallel sequence galaxy classification in which an S0a-S0b-S0c-Sph sequence of decreasing bulge-to-total ratios is juxtaposed to an Sa-Sb-Sc-Im sequence of star-forming galaxies. All parameter sequences show a complete continuity from giant galaxies to the tiniest dwarfs. Dwarfs are not a new or different class of galaxies. Rather, they are the extreme products of transformation processes that get more important as gravitational potential wells get more shallow. Smaller Sph and S+Im galaxies have lower stellar densities because they retain fewer baryons. Comparison of the baryonic parameter correlations with those for dark matter halos allows us to estimate baryon loss as a function of galaxy mass. Extreme dwarfs are almost completely dominated by dark matter.

show abstract

Dwarf Galaxies of the Local Group

Cited by 2,200 publications

References 402 publications

Kinematics of the ionized gas in the Local Group irregular galaxy IC 1613

Kinematics of the ionized gas in the Local Group irregular galaxy IC 1613

Gravitational detection of a low-mass dark satellite galaxy at cosmological distance

Structure and Evolution of Dwarf Galaxies

Contact Info

Product

Resources

About