Ionized gas discs in elliptical and S0 galaxies at z < 1

Author(s)

Yara L. Jaffé, Alfonso Aragón-Salamanca, Bodo Ziegler

Abstract

We analyse the extended, ionized-gas emission of 24 early-type galaxies (ETGs) at 0 < z < 1 from the ESO Distant Cluster Survey (EDisCS). We discuss different possible sources of ionization and favour star formation as the main cause of the observed emission. 10 galaxies have disturbed gas kinematics, while 14 have rotating gas discs. In addition, 15 galaxies are in the field, while 9 are in the infall regions of clusters. This implies that, if the gas has an internal origin, this is likely stripped as the galaxies get closer to the cluster centre. If the gas instead comes from an external source, then our results suggest that this is more likely acquired outside the cluster environment, where galaxy-galaxy interactions more commonly take place. We analyse the Tully-Fisher relation of the ETGs with gas discs, and compare them to EDisCS spirals. Taking a matched range of redshifts, M

_B < 20, and excluding galaxies with large velocity uncertainties, we find that, at fixed rotational velocity, ETGs are 1.7 mag fainter in M

_B than spirals. At fixed stellar mass, we also find that ETGs have systematically lower specific star formation rates than spirals. This study constitutes an important step forward towards the understanding of the evolution of the complex ISM in ETGs by significantly extending the look-back-time baseline explored so far.

Organisation(s)

Department of Astrophysics

External organisation(s)

Universidad de Concepción, University of Nottingham

Journal

Monthly Notices of the Royal Astronomical Society

Volume

440

Pages

3491 - 3502

No. of pages

12

ISSN

0035-8711

DOI

https://doi.org/10.1093/mnras/stu507

Publication date

06-2014

Peer reviewed

Yes

Austrian Fields of Science 2012

103003 Astronomy, 103004 Astrophysics

Keywords

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/6e113fb5-66a0-44c3-8e05-31c9cfc4cb6f