A Caltech Library Service

The 2dF Galaxy Redshift Survey: the local E+A galaxy population

Blake, Chris and Pracy, Michael B. and Couch, Warrick J. and Bekki, Kenji and Lewis, Ian and Glazebrook, Karl and Baldry, Ivan K. and Baugh, Carlton M. and Bland-Hawthorn, Joss and Bridges, Terry and Cannon, Russell and Cole, Shaun and Colless, Matthew and Collins, Chris and Dalton, Gavin and De Propris, Roberto and Driver, Simon P. and Efstathiou, George and Ellis, Richard S. and Frenk, Carlos S. and Jackson, Carole and Lahav, Ofer and Lumsden, Stuart and Maddox, Steve and Madgwick, Darren and Norberg, Peder and Peacock, John A. and Peterson, Bruce A. and Sutherland, Will and Taylor, Keith (2004) The 2dF Galaxy Redshift Survey: the local E+A galaxy population. Monthly Notices of the Royal Astronomical Society, 355 (3). pp. 713-727. ISSN 0035-8711. doi:10.1111/j.1365-2966.2004.08351.x.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


We select a sample of low-redshift (z∼ 0.1) E+A galaxies from the 2dF Galaxy Redshift Survey (2dFGRS). The spectra of these objects are defined by strong hydrogen Balmer absorption lines (Hδ, Hγ, Hβ) combined with a lack of [O ᵢᵢ] 3727-Å emission, together implying a recently truncated burst of star formation. The E+A spectrum is thus a signpost to galaxies in the process of evolution. We quantify the local environments, clustering properties and luminosity function of the E+A galaxies. We find that the environments are consistent with the ensemble of 2dFGRS galaxies: low-redshift E+A systems are located predominantly in the field, existing as isolated objects or in poor groups. However, the luminosity distribution of galaxies selected using three Balmer absorption lines Hδγβ appears more typical of ellipticals. Indeed, morphologically these galaxies are preferentially spheroidal (E/S0) systems. In a small but significant number we find evidence for recent major mergers, such as tidal tails. We infer that major mergers are one important formation mechanism for E+A galaxies, as suggested by previous studies. At low redshift the merger probability is high in the field and low in clusters, thus these recently formed spheroidal systems do not follow the usual morphology–density relation for ellipticals. Regarding the selection of E+A galaxies: we find that basing the Balmer-line criterion solely on Hδ absorption leads to a significant subpopulation of disc systems with detectable Hα emission. In these objects the [O ᵢᵢ] emission is presumably either obscured by dust or present with a low signal-to-noise ratio, whilst the (Hγ, Hβ) absorption features are subject to emission-filling.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Baugh, Carlton M.0000-0002-9935-9755
Bland-Hawthorn, Joss0000-0001-7516-4016
Colless, Matthew0000-0001-9552-8075
Ellis, Richard S.0000-0001-7782-7071
Norberg, Peder0000-0002-5875-0440
Additional Information:© 2004 RAS. Accepted 2004 August 23. Received 2004 July 22; in original form 2004 March 16. We thank Elaine Sadler for useful conversations regarding this work. CB, WJC and KB acknowledge the financial support of the Australian Research Council throughout the course of this work. MBP was supported by an Australian Postgraduate Award.
Funding AgencyGrant Number
Australian Research CouncilUNSPECIFIED
Australian Postgraduate AwardUNSPECIFIED
Subject Keywords:surveys, galaxies: formation, galaxies: interactions
Issue or Number:3
Record Number:CaltechAUTHORS:20200710-171317726
Persistent URL:
Official Citation:Chris Blake, Michael B. Pracy, Warrick J. Couch, Kenji Bekki, Ian Lewis, Karl Glazebrook, Ivan K. Baldry, Carlton M. Baugh, Joss Bland-Hawthorn, Terry Bridges, Russell Cannon, Shaun Cole, Matthew Colless, Chris Collins, Gavin Dalton, Roberto De Propris, Simon P. Driver, George Efstathiou, Richard S. Ellis, Carlos S. Frenk, Carole Jackson, Ofer Lahav, Stuart Lumsden, Steve Maddox, Darren Madgwick, Peder Norberg, John A. Peacock, Bruce A. Peterson, Will Sutherland, Keith Taylor, The 2dF Galaxy Redshift Survey: the local E+A galaxy population, Monthly Notices of the Royal Astronomical Society, Volume 355, Issue 3, December 2004, Pages 713–727,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:104344
Deposited By: Rebecca Minjarez
Deposited On:14 Jul 2020 15:36
Last Modified:16 Nov 2021 18:30

Repository Staff Only: item control page