Stellar chemo-kinematics of isolated dwarf spheroidal galaxies

2018 ◽  
Vol 14 (S344) ◽  
pp. 222-223
Author(s):  
S. Taibi ◽  
G. Battaglia ◽  
M. Rejkuba ◽  
N. Kacharov ◽  
M. Zoccali
Keyword(s):  
Galaxy Evolution ◽  
Milky Way ◽  
Local Group ◽  
Intrinsic Properties ◽  
Dwarf Spheroidal Galaxies ◽  
Preliminary Results ◽  
Low Mass ◽  
Insight Into ◽  
Spheroidal Galaxies

AbstractThe study of dwarf spheroidal galaxies (dSph) is of great importance to understand galaxy evolution at the low-mass end. In the Local Group the majority of them are found to be satellites of the Milky Way or M31. The closest ones have been studied in great detail, however it is hard to constrain if their present-day observed properties are mainly caused by internal or environmental mechanisms. In order to minimize these effects and gain an insight into their intrinsic properties, we are studying two of the three isolated dSph galaxies in the Local Group, i.e. Cetus and Tucana, located far beyond the virial radius of the Milky Way and M31. We present here results from our recently published analysis of Cetus (Taibi2018) and preliminary results for Tucana (Taibi et al. in prep.).

scholarly journals Evidence for Light-weight Local Group Dwarf Spheroidal Galaxies

2004 ◽  
Vol 220 ◽  
pp. 365-366
Author(s):  
J. R. Kuhn ◽  
D. Kocevski
Keyword(s):  
Dark Matter ◽  
Milky Way ◽  
Local Group ◽  
Light Weight ◽  
Natural Explanation ◽  
Dwarf Spheroidal Galaxies ◽  
Ursa Minor ◽  
Matter Component ◽  
Morphological State ◽  
Spheroidal Galaxies

A simple and natural explanation for the dynamics and morphology of the Local Group Dwarf Spheroidal galaxies, Draco (Dra) and Ursa Minor (UMi), is that they are weakly unbound stellar systems with no significant dark matter component. A gentle, but persistent, Milky Way (MW) tide has left them in their current kinematic and morphological state (the “parametric tidal excitation”). A new test of a dark matter dominated dS potential follows from a careful observation of the “clumpiness” of the dS stellar surface density.

scholarly journals Detailed Studies of the Sculptor Dwarf Spheroidal Galaxy in the Milky Way halo

2013 ◽  
Vol 9 (S298) ◽  
pp. 53-58 ◽  
Author(s):  
Eline Tolstoy
Keyword(s):  
Milky Way ◽  
Dwarf Galaxies ◽  
Spectroscopic Studies ◽  
Dwarf Spheroidal Galaxies ◽  
Low Mass ◽  
Milky Way Halo ◽  
Spheroidal Galaxies

AbstractIn and around the Milky Way halo there are a number of low mass low luminosity dwarf galaxies. Several of these systems have been studied in great detail. I describe recent photometric and spectroscopic studies of the Sculptor dwarf spheroidal galaxy made as part of the DART survey of nearby dwarf spheroidal galaxies.

The Local Group Dwarf Spheroidal Galaxies: A Key to Building Blocks in the Universe

2005 ◽  
Vol 201 ◽  
pp. 469-470
Author(s):  
Hiroyuki. Hirashita ◽  
Naoyuki. Tamura ◽  
Tsutomu T. Takeuchi
Keyword(s):  
Star Formation ◽  
Local Group ◽  
Building Blocks ◽  
Star Formation History ◽  
High Mass ◽  
Dwarf Spheroidal Galaxies ◽  
The Hierarchical Structure ◽  
History Of ◽  
Low Mass ◽  
Spheroidal Galaxies

Recent studies have been revealing the properties of dwarf spheroidal galaxies (dSphs). Their low mass indicates that the dSphs may provide a clue to physical properties of the building blocks in the hierarchical structure formation. We select the Local Group dSphs as a sample. To obtain the information on the star formation history of dSphs, we investigate the relation between their metallicity and virial mass. According to our scenario, the star formation efficiency of the dSphs is low because of strong regulation. This is consistent with their high mass-to-light ratios. We also comment on the environmental effects on the dSphs.

scholarly journals Observed Properties of Dark Matter on Small Spatial Scales

2007 ◽  
Vol 3 (S244) ◽  
pp. 44-52 ◽  
Author(s):  
Rosemary F.G. Wyse ◽  
Gerard Gilmore
Keyword(s):  
Dark Matter ◽  
Galaxy Evolution ◽  
Local Group ◽  
Spatial Scales ◽  
Critical Role ◽  
Large Datasets ◽  
Dwarf Spheroidal Galaxies ◽  
Internal Motions ◽  
Spheroidal Galaxies

AbstractThe nature of dark matter is one of the outstanding questions of astrophysics. The internal motions of member stars reveal that the lowest luminosity galaxies in the Local Group are the most dark-matter dominated. New large datasets allow one to go further, and determine systematic properties of their dark matter haloes. We summarise recent results, emphasising the critical role of the dwarf spheroidal galaxies in understanding both dark matter and baryonic processes that shape galaxy evolution.

The role of internal feedback in the evolution of the dwarf spheroidal galaxy Leo II

2019 ◽  
Vol 15 (S359) ◽  
pp. 278-279
Author(s):  
Roberto Hazenfratz ◽  
Gustavo A. Lanfranchi ◽  
Anderson Caproni
Keyword(s):  
Large Distance ◽  
Milky Way ◽  
Local Group ◽  
Galactic Evolution ◽  
External Effects ◽  
Dwarf Spheroidal Galaxies ◽  
First Results ◽  
Formation And Evolution ◽  
Spheroidal Galaxies

AbstractThis work aims to explore the different processes of formation and evolution of dwarf spheroidal galaxies in the Local Group analyzing internal and external feedbacks, taking Leo II as a model of parametrization due to its adequate large distance to the Milky Way, in order to minimize potential external effects. We present a discussion of the first results regarding the processes of formation and galactic evolution from the gas hydrodynamics. Combined with previous studies for other similar systems, such results have the potential to establish strong links for the elaboration of a consistent and coherent scenario of formation and evolution of the dwarf spheroidal galaxies in the Local Group.

scholarly journals Variable Stars in Dwarf Spheroidal Galaxies

1973 ◽  
Vol 21 ◽  
pp. 35-48
Author(s):  
Steven Van Agt
Keyword(s):  
Globular Clusters ◽  
Local Group ◽  
Elliptical Galaxies ◽  
Variable Stars ◽  
Dwarf Spheroidal Galaxies ◽  
Theoretical Predictions ◽  
History Of ◽  
Set Up ◽  
Theoretical Considerations ◽  
Spheroidal Galaxies

Interest in dwarf spheroidal galaxies is motivated by a number of reasons; an important one on the occasion of this colloquium is the abundance of variable stars. The theory of stellar evolution and stellar pulsations is now able to predict from theoretical considerations characteristic properties of variable stars in the colour-magnitude diagram (Iben, 1971). By observing the variable stars in the field, and in as wide a selection of objects as possible, more insight can be obtained into the history of the oldest members of our Galaxy (the globular clusters) and of the dwarf spheroidal galaxies in the Local Group. It is worthwhile to explore the spheroidal galaxies as observational tests for the theoretical predictions of conditions in space away from our Galaxy. The numbers of variable stars in the dwarf spheroidal galaxies are such that we may expect well-defined relations to emerge once reliable magnitude sequences have been set up, the variable stars found, and their periods determined. Six dwarf spheroidal galaxies are presently known in the Local Group within a distance of 250 kpc. In Table I, which lists members of the Local Group, they are at the low-luminosity end of the sequence of elliptical galaxies (van den Bergh, 1968).

Chemical composition of globular clusters in dwarf galaxies

2019 ◽  
Vol 14 (S351) ◽  
pp. 317-320
Author(s):  
Søren S. Larsen
Keyword(s):  
Chemical Composition ◽  
Globular Clusters ◽  
Milky Way ◽  
Local Group ◽  
Dwarf Galaxies ◽  
Chemical Abundances ◽  
Preliminary Results ◽  
Detailed Chemical

AbstractThis contribution gives an update on on-going efforts to characterise the detailed chemical abundances of Local Group globular clusters (GCs) from integrated-light spectroscopy. Observations of a sample of 20 GCs so far, located primarily within dwarf galaxies, show that at low metallicities the [α/Fe] ratios are generally indistinguishable from those in Milky Way GCs. However, the “knee” above which [α/Fe] decreases towards Solar-scaled values occurs at lower metallicities in the dwarfs, implying that GCs follow the same trends seen in field stars. Efforts are underway to establish NLTE corrections for integrated-light abundance measurements, and preliminary results for Mn are discussed.

scholarly journals THE MASSES OF LOCAL GROUP DWARF SPHEROIDAL GALAXIES: THE DEATH OF THE UNIVERSAL MASS PROFILE

2014 ◽  
Vol 783 (1) ◽  
pp. 7 ◽  
Author(s):  
Michelle L. M. Collins ◽  
Scott C. Chapman ◽  
R. M. Rich ◽  
Rodrigo A. Ibata ◽  
Nicolas F. Martin ◽  
...  
Keyword(s):  
Local Group ◽  
Dwarf Spheroidal Galaxies ◽  
Mass Profile ◽  
The Masses ◽  
Spheroidal Galaxies
Sign in / Sign up

Export Citation Format

Share Document