The Next Generation Virgo Cluster Survey. XXII. Shell Feature Early-type Dwarf Galaxies in the Virgo Cluster

Journal
Date Issued
2017
Author(s)
Paudel, Sanjaya
•
Smith, Rory
•
Duc, Pierre-Alain
•
Côté, Patrick
•
Cuillandre, Jean-Charles
•
Ferrarese, Laura
•
Blakeslee, John P.
•
Boselli, Alessandro
•
•
Gwyn, S. D. J.
•
Guhathakurta, Puragra
•
Mei, Simona
•
Mihos, J. Christopher
•
Peng, Eric W.
•
Powalka, Mathieu
•
Sánchez-Janssen, Rúben
•
Toloba, Elisa
•
Zhang, Hongxin
DOI
Abstract
The Next Generation Virgo Cluster Survey is a deep (with a 2σ detection limit μg = 29 mag arcsec-2 in the g-band) optical panchromatic survey targeting the Virgo cluster from its core to virial radius, for a total areal coverage of 104 square degrees. As such, the survey is well suited for the study of galaxies’ outskirts, haloes, and low surface brightness features that arise from dynamical interactions within the cluster environment. We report the discovery of extremely faint (μg > 25 mag arcsec-2) shells in three Virgo cluster early-type dwarf galaxies: VCC 1361, VCC 1447, and VCC 1668. Among them, VCC 1447 has an absolute magnitude Mg = -11.71 mag and is the least massive galaxy with a shell system discovered to date. We present a detailed study of these low surface brightness features. We detect between three and four shells in each of our galaxies. Within the uncertainties, we find no evidence of a color difference between the galaxy main body and shell features. The observed arcs of the shells are located up to several effective radii of the galaxies. We further explore the origin of these low surface brightness features with the help of idealized numerical simulations. We find that a near equal mass merger is best able to reproduce the main properties of the shells, including their quite symmetric appearance and their alignment along the major axis of the galaxy. The simulations provide support for a formation scenario in which a recent merger, between two near-equal mass, gas-free dwarf galaxies, forms the observed shell systems.

Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

Volume
834
Issue
1
Start page
66
Uri
Url
Issn Identifier
0004-637X
Ads BibCode
2017ApJ...834...66P
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Paudel_2017_ApJ_834_66.pdf

Description
PDF editoriale
Size

3.58 MB

Format

Adobe PDF

Checksum (MD5)

b7565343b3c1397b0db5dfd596fa09ed