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Related papers: Ultra Diffuse Dwarf Galaxies Hosting Pseudo-bulges

200 papers

For almost two decades the properties of "dwarf" galaxies have challenged the Cold Dark Matter (CDM) paradigm of galaxy formation. Most observed dwarf galaxies consists of a rotating stellar disc embedded in a massive DM halo with a near…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Fabio Governato , Chris Brook , Lucio Mayer , Alyson Brooks , George Rhee , James Wadsley , Patrik Jonsson , Beth Willman , Greg Stinson , Thomas Quinn , Piero Madau

We present the H$\alpha$ images of ultra-flat (UF) spiral galaxies seen practically edge-on. The galaxies have the angular diameter in the $B$ band $a> 1.9^{\prime}$ and the apparent axial ratio $(a/b) >10$. We found that their H$\alpha$…

Astrophysics of Galaxies · Physics 2020-04-22 S. S. Kaisin , I. D. Karachentsev , H. Hernandez-Toledo , L. Gutierrez , V. E. Karachentseva

The dominant physical formation mechanism(s) for ultra-diffuse galaxies (UDGs) is still poorly understood. Here, we combine new, deep imaging from the Jeanne Rich Telescope with deep integral field spectroscopy from the Keck II telescope to…

I compare the dark matter content within stellar half-mass radius expected in a $\Lambda$CDM-based galaxy formation model with existing observational estimates for the observed dwarf satellites of the Milky Way and ultra-diffuse galaxies…

Astrophysics of Galaxies · Physics 2024-12-19 Andrey Kravtsov

Galaxies are thought to grow through accretion; as less massive galaxies are disrupted and merge over time, their debris results in diffuse, clumpy stellar halos enveloping the central galaxy. Here we present a study of the variation in the…

Astrophysics of Galaxies · Physics 2016-10-19 Allison Merritt , Pieter van Dokkum , Roberto Abraham , Jielai Zhang

Many ultra diffuse galaxies (UDGs) have now been identified in clusters of galaxies. However, the number of nearby UDGs suitable for detailed follow-up remain rare. Our aim is to begin to identify UDGs in the environments of nearby bright…

It is clear that within the class of ultra-diffuse galaxies (UDGs) there is an extreme range in the richness of their associated globular cluster (GC) systems. Here, we report the structural properties of five UDGs in the Perseus cluster…

Supernovae feedback driven expansion has proven to be a viable mechanism to explain the average properties of Ultra Diffuse Galaxies (UDGs) such as the sizes, colors, mass and internal kinematics. Here, we explore the origin of stellar…

Astrophysics of Galaxies · Physics 2022-11-30 S. Cardona-Barrero , A. Di Cintio , G. Battaglia , A. V. Macciò , S. Taibi

We recently identified a population of low surface brightness objects in the field of the z=0.023 Coma cluster, using the Dragonfly Telephoto Array. Here we present Keck spectroscopy of one of the largest of these "ultra-diffuse galaxies"…

Recently a population of large, very low surface brightness, spheroidal galaxies was identified in the Coma cluster. The apparent survival of these Ultra Diffuse Galaxies (UDGs) in a rich cluster suggests that they have very high masses.…

We present a spectroscopic study of the ``Disco Ball'' (SMDG0038365-064207), a rotationally-supported, red-sequence, ultra-diffuse galaxy (UDG) with a nuclear star cluster (NSC), multiple stellar clusters, and active star-forming regions…

Astrophysics of Galaxies · Physics 2025-08-15 Donghyeon J. Khim , Dennis Zaritsky , Loraine Sandoval Ascencio , M. C. Cooper , Richard Donnerstein

Now almost 70 years since its introduction, the effective or half-light radius has become a very popular choice for characterising galaxy size. However, the effective radius measures the concentration of light within galaxies and thus does…

Astrophysics of Galaxies · Physics 2020-01-10 Nushkia Chamba , Ignacio Trujillo , Johan H. Knapen

The far-ultraviolet (UV) counts and the deep optical spectroscopic surveys have revealed an unexpected number of very blue galaxies (vBG). Using constraints from the UV and optical, we apply the galaxy evolution model PEGASE (Fioc &…

Astrophysics · Physics 2007-05-23 Michel Fioc , Brigitte Rocca-Volmerange

In this paper we report on the discovery of 27 low-surface brightness galaxies, of which 12 are candidate ultra-diffuse galaxy (UDG) in the Hydra I cluster, based on deep observations taken as part of the VST Early-type Galaxy Survey…

In this study, we compare the structural parameters of ultra-diffuse galaxies (UDGs) to those of other dwarf galaxies and investigate whether UDGs form a distinct population. We observed deep $u'$-, $g'$-, and $r'$-band images (maximum…

Astrophysics of Galaxies · Physics 2024-03-18 Raphael Zöller , Matthias Kluge , Benjamin Staiger , Ralf Bender

We used the $H\alpha$ images from a large sample of nearby late-type dwarf galaxies to investigate properties of their emission structure. The sample consists of three hundred galaxies of the irregular (Irr), Magellanic irregular (Im), blue…

Astrophysics of Galaxies · Physics 2020-12-16 Karachentsev I. D. , Kaisin S. S

We have found the atomic gas (HI) reservoirs of the blue ultra diffuse galaxy (UDG) candidates identified by R\'oman and Trujillo in images near Hickson Compact Groups (HCGs). We confirm that all of the objects are indeed UDGs with…

Astrophysics of Galaxies · Physics 2018-03-14 Kristine Spekkens , Ananthan Karunakaran

Ultra-diffuse galaxies (UDGs) are attractive candidates to probe cosmological models and test theories of galaxy formation at low masses; however, they are difficult to detect because of their low surface brightness. In the Local Group a…

We find that the minor axes of the ultra-diffuse galaxies (UDGs) in Abell 2634 tend to be aligned with the major axis of the central dominant galaxy, at a $\gtrsim 95\%$ confidence level. This alignment is produced by the bright UDGs with…

Astrophysics of Galaxies · Physics 2020-07-30 Yu Rong , Pavel E. Mancera Piña , Elmo Tempel , Thomas H. Puzia , Sven De Rijcke

Leveraging spectroscopic data from the Sloan Digital Sky Survey, we conduct a comprehensive analysis of the central stellar velocity dispersion, stellar population properties, star formation history, and gas-phase chemical abundances in…

Astrophysics of Galaxies · Physics 2025-06-10 Shihong Liu , Yu Rong , Huiyuan Wang , Hong-Xin Zhang , Tie Li , Yao Yao , Zhicheng He , Teng Liu , Enci Wang , Cheng Cheng , Xu Kong