Virgo Cluster Early-Type Dwarf Galaxies with the Sloan Digital Sky Survey. I. On the Possible Disk Nature of Bright Early-Type Dwarfs

AbstractWe identify gravitationally bound structures in the Ursa Major region using positions, velocities and photometry from the Sloan Digital Sky Survey (SDSS DR7) and the Third Reference Catalogue of Bright Galaxies (RC3). A friends-of-friends algorithm is extensively tested on mock galaxy lightcones and then implemented on the real data to determine galaxy groups whose members are likely to be physically and dynamically associated with one another. We find several galaxy groups within the region that are likely bound to one another and in the process of merging. We classify 6 galaxy groups as the Ursa Major ‘supergroup’, which are likely to merge and form a poor cluster with a mass of ~ 8 × 1013 M⊙. Furthermore, the Ursa Major supergroup as a whole is likely bound to the Virgo cluster, which will eventually form an even larger system in the context of hierarchical structure formation. We investigate the evolutionary state of the galaxy groups in the Ursa Major region and conclude that these groups are in an early evolutionary state and the properties of their member galaxies are similar to those in the field.

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COLOR–MAGNITUDE RELATIONS OF EARLY-TYPE DWARF GALAXIES IN THE VIRGO CLUSTER: AN ULTRAVIOLET PERSPECTIVE

The Astrophysical Journal ◽

10.1088/2041-8205/721/1/l72 ◽

2010 ◽

Vol 721 (1) ◽

pp. L72-L77 ◽

Cited By ~ 17

Author(s):

Suk Kim ◽

Soo-Chang Rey ◽

Thorsten Lisker ◽

Sangmo Tony Sohn

Keyword(s):

Dwarf Galaxies ◽

Virgo Cluster ◽

Early Type

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Star formation in low-redshift cluster dwarf galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa697 ◽

2020 ◽

Vol 493 (4) ◽

pp. 5625-5635

Author(s):

Cody M Rude ◽

Madina R Sultanova ◽

Gihan L Ipita Kaduwa Gamage ◽

Wayne A Barkhouse ◽

Sandanuwan P Kalawila Vithanage

Keyword(s):

Star Formation ◽

Dwarf Galaxies ◽

Sloan Digital Sky Survey ◽

Galaxy Interactions ◽

Cluster Data ◽

Luminosity Functions ◽

Sky Survey ◽

Ram Pressure ◽

Low Mass ◽

Central Concentration

ABSTRACT Evolution of galaxies in dense environments can be affected by close encounters with neighbouring galaxies and interactions with the intracluster medium. Dwarf galaxies (dGs) are important as their low mass makes them more susceptible to these effects than giant systems. Combined luminosity functions (LFs) in the r and u band of 15 galaxy clusters were constructed using archival data from the Canada–France–Hawaii Telescope. LFs were measured as a function of clustercentric radius from stacked cluster data. Marginal evidence was found for an increase in the faint-end slope of the u-band LF relative to the r-band with increasing clustercentric radius. The dwarf-to-giant ratio (DGR) was found to increase toward the cluster outskirts, with the u-band DGR increasing faster with clustercentric radius compared to the r-band. The dG blue fraction was found to be ∼2 times larger than the giant galaxy blue fraction over all clustercentric distance (∼5σ level). The central concentration (C) was used as a proxy to distinguish nucleated versus non-nucleated dGs. The ratio of high-C to low-C dGs was found to be ∼2 times greater in the inner cluster region compared to the outskirts (2.8σ level). The faint-end slope of the r-band LF for the cluster outskirts (0.6 ≤ r/r200 < 1.0) is steeper than the Sloan Digital Sky Survey field LF, while the u-band LF is marginally steeper at the 2.5σ level. Decrease in the faint-end slope of the r- and u-band cluster LFs towards the cluster centre is consistent with quenching of star formation via ram pressure stripping and galaxy–galaxy interactions.

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Origin of Nonaxisymmetric Features of Virgo Cluster Early-type Dwarf Galaxies. II. Tidal Effects on Disk Features and Stability

The Astrophysical Journal ◽

10.3847/1538-4357/ab5716 ◽

2019 ◽

Vol 887 (2) ◽

pp. 139 ◽

Cited By ~ 2

Author(s):

SungWon Kwak ◽

Woong-Tae Kim ◽

Soo-Chang Rey ◽

Thomas R. Quinn

Keyword(s):

Dwarf Galaxies ◽

Virgo Cluster ◽

Early Type ◽

Tidal Effects

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Globular Clusters, Dwarf Galaxies, and the Assembly of the M87 Halo

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315009837 ◽

2015 ◽

Vol 11 (S317) ◽

pp. 153-158

Author(s):

Eric W. Peng ◽

Hong-Xin Zhang ◽

Chengze Liu ◽

Yiqing Liu

Keyword(s):

Globular Clusters ◽

Dwarf Galaxies ◽

Galaxy Cluster ◽

Virgo Cluster ◽

Early Type ◽

Massive Galaxies ◽

Low Mass ◽

Using Data ◽

The Relationship ◽

Negative Gradient

AbstractAt the center of the nearest galaxy cluster, the Virgo cluster, lies the massive cD galaxy, M87 (NGC 4486). Using data from the Next Generation Virgo Cluster Survey, we investigate the relationship between M87, its globular clusters (GCs), and satellite dwarf galaxies. We find that the kinematics of GCs and ultra-compact dwarfs (UCDs) are different, indicating that UCDs are not simply massive GCs. We also identify a morphological sequence of envelope fraction around UCDs correlated with cluster-centric distance that suggest UCDs are the result of tidal stripping. Lastly, we find that the [α/Fe] abundance ratios of low-mass early-type galaxies in Virgo exhibit a strong negative gradient within ~ 400 kpc of M87, where the galaxies closest to M87 have the highest values. These satellite galaxies are likely the surviving counterparts of accreted dwarfs that contribute stars to the metal-poor, α-rich stellar halos of massive galaxies. Together, these results describe a dense environment that has had a strong and continuing impact on the evolution of its low-mass neighbors.

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