The Next Generation Virgo Cluster Survey (NGVS). XXX. Ultra-diffuse Galaxies and Their Globular Cluster Systems

Authors

• Sungsoon Lim, National Research Council Canada
• Patrick Côté, National Research Council Canada
• Eric W. Peng, Peking University
• Laura Ferrarese, National Research Council Canada
• Joel C. Roediger, National Research Council Canada
• Patrick R. Durrell, Youngstown State University
• J. C. Mihos, Case Western Reserve University
• Kaixiang Wang, Peking University
• S. D.J. Gwyn, National Research Council Canada
• Jean-Charles Cuillandre, Astrophysique, Instrumentation et Modélisation de Paris-Saclay
• Chengze Liu, Shanghai Jiao Tong University
• Rubén Sánchez-Janssen, Royal Observatory
• Elisa Toloba, University of the PacificFollow
• Laura V. Sales, University of California, Riverside
• Puragra Guhathakurta, Lick Observatory
• Ariane Lancon, Université de Strasbourg
• Thomas H. Puzia, Pontificia Universidad Católica de Chile

Document Type

Article

Publication Title

Astrophysical Journal

Department

Physics

ISSN

15384357

Volume

899

Issue

1

DOI

10.3847/1538-4357/aba433

First Page

1

Last Page

23

Publication Date

8-13-2020

Abstract

We present a study of ultra-diffuse galaxies (UDGs) in the Virgo Cluster based on deep imaging from the Next Generation Virgo Cluster Survey. Applying a new definition for the UDG class based on galaxy scaling relations, we define samples of 44 and 26 UDGs using expansive and restrictive selection criteria, respectively. Our UDG sample includes objects that are significantly fainter than previously known UDGs: i.e., more than half are fainter than <μ>e∼ 27.5 mag arcsec-2. The UDGs in Virgo's core region show some evidence for being structurally distinct from "normal"dwarf galaxies, but this separation disappears when considering the full sample of galaxies throughout the cluster. UDGs are more centrally concentrated in their spatial distribution than other Virgo galaxies of similar luminosity, while their morphologies demonstrate that at least some UDGs owe their diffuse nature to physical processes - such as tidal interactions or low-mass mergers - that are at play within the cluster environment. The globular cluster (GC) systems of Virgo UDGs have a wide range in specific frequency (S N), with a higher mean S N than "normal"Virgo dwarfs, but a lower mean S N than Coma UDGs at fixed luminosity. Their GCs are predominantly blue, with a small contribution from red clusters in the more massive UDGs. The combined GC luminosity function is consistent with those observed in dwarf galaxies, showing no evidence of being anomalously luminous. The diversity in their morphologies and their GC properties suggests no single process has given rise to all objects within the UDG class. Based on the available evidence, we conclude that UDGs are simply those systems that occupy the extended tails of the galaxy size and surface brightness distributions.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Recommended Citation

Lim, Sungsoon; Côté, Patrick; Peng, Eric W.; Ferrarese, Laura; Roediger, Joel C.; Durrell, Patrick R.; Mihos, J. C.; Wang, Kaixiang; Gwyn, S. D.J.; Cuillandre, Jean-Charles; Liu, Chengze; Sánchez-Janssen, Rubén; Toloba, Elisa; Sales, Laura V.; Guhathakurta, Puragra; Lancon, Ariane; and Puzia, Thomas H., "The Next Generation Virgo Cluster Survey (NGVS). XXX. Ultra-diffuse Galaxies and Their Globular Cluster Systems" (2020). Pacific Faculty Work. 300.
https://scholarlycommons.pacific.edu/all-faculty/300