EDP Sciences
Free Access
Issue
A&A
Volume 391, Number 3, September I 2002
Page(s) 823 - 831
Section Extragalactic astronomy
DOI https://doi.org/10.1051/0004-6361:20020875


A&A 391, 823-831 (2002)
DOI: 10.1051/0004-6361:20020875

More evidence for hidden spiral and bar features in bright early-type dwarf galaxies

F. D. Barazza1, B. Binggeli1 and H. Jerjen2

1  Astronomisches Institut, Universität Basel, Venusstrasse 7, 4102 Binningen, Switzerland
2  Research School of Astronomy and Astrophysics, The Australian National University, Mt Stromlo Observatory, Cotter Road, Weston ACT 2611, Australia

(Received 25 February 2002 / Accepted 31 May 2002)

Abstract
Following the discovery of spiral structure in IC 3328 (Jerjen et al. 2000), we present further evidence that a sizable fraction of bright early-type dwarfs in the Virgo cluster are genuine disk galaxies, or are hosting a disk component. Among a sample of 23 nucleated dwarf ellipticals and dS0s observed with the Very Large Telescope in B and R, we found another four systems exhibiting non-axisymmetric structures, such as a bar and/or spiral arms, indicative of a disk (IC 0783, IC 3349, NGC 4431, IC 3468). Particularly remarkable are the two-armed spiral pattern in IC 0783 and the bar and trailing arms in NGC 4431. For both galaxies the disk nature has recently been confirmed by a rotation velocity measurement (Simien & Prugniel 2002). Our photometric search is based on a Fourier decomposition method and a specific version of unsharp masking. Some "early-type" dwarfs in the Virgo cluster seem to be former late-type galaxies which were transformed to early-type morphology, e.g. by "harassment", during their infall to the cluster, while maintaining part of their disk structure.


Key words: galaxies: general -- galaxies: fundamental parameters -- galaxies: photometry -- galaxies: structure

Offprint request: F. D. Barazza, barazza@astro.unibas.ch

SIMBAD Objects



© ESO 2002

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.