Cluster galaxies at redshift 1.4

V. Strazzullo, P. Rosati, C. Lidman, C. Mullis, R. Demarco, R. Gobat, M. Nonino

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


We present new and partly preliminary results on the galaxy populations in the massive, X-ray luminous cluster XMMU J2235-2557 at redshift 1.39. We use high-quality optical and NIR data to study the luminosity function of cluster galaxies at different wavelengths (restframe ≈ 3500, 6500, 9000 Å), confirming previous results at lower redshifts showing that the redshift evolution of the characteristic luminosity M* of the luminosity function is consistent with passive evolution of a stellar population formed at redshift z>2. We build a restframe U-R vs R color-magnitude diagram from high-resolution z- and H-band images of XMMU J2235-2557 within R ≈ 700 kpc, finding a tight red sequence already in place. When compared to models of elliptical galaxy formation [1], the slope and location of the red sequence indicate a formation redshift of z ≈ 3 for the bulk of the stars in red sequence galaxies, at least brighter than M*+l. Spectral energy distribution fitting of multicolor data sampling the restframe ≈ 2700 9000 Å wavelength range consistently indicates that cluster members on the red sequence are already massive galaxies hosting evolved stellar populations.

Original languageEnglish
Title of host publicationProbing Stellar Populations Out To The Distant Universe - Cefalu 2008 - Proceedings of the International Conference
Number of pages4
StatePublished - 2009
Externally publishedYes
EventInternational Conference on Probing Stellar Populations Out To The Distant Universe, Cefalu 2008 - Cefalu, Sicily, Italy
Duration: 7 Sep 200819 Sep 2008

Publication series

NameAIP Conference Proceedings
ISSN (Print)0094-243X
ISSN (Electronic)1551-7616


ConferenceInternational Conference on Probing Stellar Populations Out To The Distant Universe, Cefalu 2008
CityCefalu, Sicily


  • Clusters
  • Evolution - galaxies
  • Formation
  • Galaxies
  • General - galaxies


Dive into the research topics of 'Cluster galaxies at redshift 1.4'. Together they form a unique fingerprint.

Cite this