A1 Refereed original research article in a scientific journal
On the accretion of a new group of galaxies on to Virgo: I. Internal kinematics of nine in-falling dEs
Authors: Bidaran B, Pasquali A, Lisker T, Coccato L, Falcon-Barroso J, van de Ven G, Peletier R, Emsellem E, Grebel EK, La Barbera F, Janz J, Sybilska A, Vijayaraghavan R, Gallagher J, Gadotti DA
Publisher: OXFORD UNIV PRESS
Publication year: 2020
Journal: Monthly Notices of the Royal Astronomical Society
Journal name in source: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Journal acronym: MON NOT R ASTRON SOC
Volume: 497
Issue: 2
First page : 1904
Last page: 1924
Number of pages: 21
ISSN: 0035-8711
eISSN: 1365-2966
DOI: https://doi.org/10.1093/mnras/staa2097
Self-archived copy’s web address: https://research.utu.fi/converis/portal/detail/Publication/50441495
Galaxy environment has been shown to play an important role in transforming late-type, star-forming galaxies to quiescent spheroids. This transformation is expected to be more severe for low-mass galaxies (M < 10(10) M-circle dot) in dense galaxy groups and clusters, mostly due to the influence of their past host haloes (also known as pre-processing) and their present-day environments. For the first time, in this study, we investigate a sample of nine early-type dwarf galaxies (dEs) that were accreted as a likely bound group on to the Virgo galaxy cluster about 2-3 Gyr ago. Considering this special condition, these nine dEs may provide a test bed for distinguishing between the influence of the Virgo galaxy cluster and the effects of the previous host halo on their current properties. Specifically, we use vr-umusF integral-field unit spectra to derive their kinematics and specific angular momentum (lambda(R)) profiles. Wc observe a spread in the lambda(R) profiles of our sample dEs, finding that the lambda(R) profiles of half of them are as high as those of low-mass field galaxies. The remaining dEs exhibit lambda(R) profiles as low as those of Virgo dEs that were likely accreted longer ago. Moreover, we detect nebular emission in one dE with a gas velocity offset suggesting ongoing gas stripping in Virgo. We suggest that the low-lambda(R) dEs in our sample were processed by their previous host halo, prior to their infall to Virgo, and that the high-lambda(R) dEs may be experiencing ram pressure stripping in Virgo.
Downloadable publication This is an electronic reprint of the original article. |  |
