Neutral hydrogen gas, past and future star formation in galaxies in and around the 'Sausage' merging galaxy cluster

Stroe, Andra and Oosterloo, Tom and Röttgering, Huub J A and Sobral, David and van Weeren, Reinout and Dawson, William (2015) Neutral hydrogen gas, past and future star formation in galaxies in and around the 'Sausage' merging galaxy cluster. Monthly Notices of the Royal Astronomical Society, 452 (3). pp. 2731-2744. ISSN 0035-8711

[img]
Preview
PDF (1506.08822)
1506.08822.pdf - Accepted Version

Download (902kB)

Abstract

CIZA J2242.8+5301 (z=0.188, nicknamed 'Sausage') is an extremely massive (M200 ~2.0 × 1015 M⊙), merging cluster with shock waves towards its outskirts, which was found to host numerous emission line galaxies. We performed extremely deep Westerbork Synthesis Radio Telescope HI observations of the 'Sausage' cluster to investigate the effect of the merger and the shocks on the gas reservoirs fuelling present and future star formation (SF) in cluster members. By using spectral stacking, we find that the emission line galaxies in the 'Sausage' cluster have, on average, as much HI gas as field galaxies (when accounting for the fact cluster galaxies are more massive than the field galaxies), contrary to previous studies. Since the cluster galaxies are more massive than the field spirals, they may have been able to retain their gas during the cluster merger. The large HI reservoirs are expected to be consumed within ~0.75-1.0 Gyr by the vigorous SF and active galactic nuclei activity and/or driven out by the outflows we observe. We find that the star formation rate (SFR) in a large fraction of Hα emission line cluster galaxies correlates well with the radio broad-band emission, tracing supernova remnant emission. This suggests that the cluster galaxies, all located in post-shock regions, may have been undergoing sustained SFR for at least 100 Myr. This fully supports the interpretation proposed by Stroe et al. and Sobral et al. that gas-rich cluster galaxies have been triggered to form stars by the passage of the shock.

Item Type:
Journal Article
Journal or Publication Title:
Monthly Notices of the Royal Astronomical Society
Additional Information:
This is a pre-copy-editing, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The definitive publisher-authenticated version Andra Stroe, Tom Oosterloo, Huub J. A. Röttgering, David Sobral, Reinout van Weeren, and William Dawson Neutral hydrogen gas, past and future star formation in galaxies in and around the ‘Sausage’ merging galaxy cluster MNRAS (September 21, 2015) Vol. 452 2731-2744 doi:10.1093/mnras/stv1462 First published online July 25, 2015
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/3100/3103
Subjects:
ID Code:
77720
Deposited By:
Deposited On:
18 Jan 2016 10:06
Refereed?:
Yes
Published?:
Published
Last Modified:
07 Apr 2020 03:34