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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - The ratio of luminous to faint red-sequence galaxies in X-ray and optically selected low-redshift clusters
AU - Capozzi, Diego
AU - Collins, Chris A.
AU - Stott, John P.
PY - 2010/4/11
Y1 - 2010/4/11
N2 - We study the ratio of luminous to faint red-sequence galaxies in both optically and X-ray selected galaxy clusters in the poorly studied redshift range 0.05 ≤ z <0.19. The X-ray-selected sample consists of 112 clusters based on the ROSAT All-Sky Survey, while the optical sample consists of 266 clusters from the Sloan Digital Sky Survey. Our results are consistent with the presence of a trend in luminous-to-faint ratio with redshift, confirming that downsizing is continuous from high to low redshift.After correcting for the variations with redshift using a partial Spearman analysis, we find no significant relationship between luminous-to-faint ratio and X-ray luminosity of the host cluster sample, in contrast to recent suggestions. Finally, we investigate the stacked colour-magnitude relations of these samples, finding no significant differences between the slopes for optically and X-ray selected clusters. The colour-magnitude slopes are consistent with the values obtained in similar studies, but not with predictions of theoretical models.
AB - We study the ratio of luminous to faint red-sequence galaxies in both optically and X-ray selected galaxy clusters in the poorly studied redshift range 0.05 ≤ z <0.19. The X-ray-selected sample consists of 112 clusters based on the ROSAT All-Sky Survey, while the optical sample consists of 266 clusters from the Sloan Digital Sky Survey. Our results are consistent with the presence of a trend in luminous-to-faint ratio with redshift, confirming that downsizing is continuous from high to low redshift.After correcting for the variations with redshift using a partial Spearman analysis, we find no significant relationship between luminous-to-faint ratio and X-ray luminosity of the host cluster sample, in contrast to recent suggestions. Finally, we investigate the stacked colour-magnitude relations of these samples, finding no significant differences between the slopes for optically and X-ray selected clusters. The colour-magnitude slopes are consistent with the values obtained in similar studies, but not with predictions of theoretical models.
KW - Galaxies: clusters: general
KW - Galaxies: evolution
KW - Galaxies: photometry
KW - Large-scale structure of Universe
U2 - 10.1111/j.1365-2966.2009.16220.x
DO - 10.1111/j.1365-2966.2009.16220.x
M3 - Journal article
AN - SCOPUS:77953075746
VL - 403
SP - 1274
EP - 1282
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 3
ER -