Star-forming fractions and galaxy evolution with redshift in rich X-ray-selected galaxy clusters

We have compared stacked spectra of galaxies, grouped by environment and stellar mass, among 58 members of the redshift z = 1.24 galaxy cluster RDCS J1252.9-2927 (J1252.9) and 134 galaxies in the z = 0.84 cluster RX J0152.7-1357 (J0152.7). These two clusters are excellent laboratories to study how g...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2013-06
Main Authors: Nantais, J B, Rettura, A, Lidman, C, Demarco, R, Gobat, R, Rosati, P, Jee, M J
Format: Article
Language:English
Subjects:
Density
Galactic clusters
Galactic evolution
Galaxies
Red shift
Spectra
Star & galaxy formation
Star formation
Stars & galaxies
Stellar evolution
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We have compared stacked spectra of galaxies, grouped by environment and stellar mass, among 58 members of the redshift z = 1.24 galaxy cluster RDCS J1252.9-2927 (J1252.9) and 134 galaxies in the z = 0.84 cluster RX J0152.7-1357 (J0152.7). These two clusters are excellent laboratories to study how galaxies evolve from star-forming to passive at z ~ 1. We measured spectral indices and star-forming fractions for our density- and mass-based stacked spectra. The star-forming fraction among low-mass galaxies (< 7 x 10^10 M_sun) is higher in J1252.9 than in J0152.7, at about 4 sigma significance. Thus star formation is being quenched between z = 1.24 and z = 0.84 for a substantial fraction of low-mass galaxies. Star-forming fractions were also found to be higher in J1252.9 in all environments, including the core. Passive galaxies in J1252.9 have systematically lower D_n4000 values than in J0152.7 in all density and mass groups, consistent with passive evolution at modestly super-solar metallicities.
ISSN:2331-8422
DOI:10.48550/arxiv.1306.3431