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arXiv · astro-ph/9801277

The K-band Hubble diagram for the brightest cluster galaxies: a test of hierarchical galaxy formation models

Abstract

We analyse the K-band Hubble diagram for a sample of brightest cluster galaxies (BCGs) in the redshift range 0 2) that is evolving passively. We can thus use evolutionary population synthesis models to estimate the rate of growth in stellar mass for these systems. We find that the stellar mass in a typical BCG has grown by a factor ~ 2 since z=1 if q_0=0.0 or by factor ~ 4 if q_0=0.5. These results are in good agreement with the predictions of semi-analytic models of galaxy formation and evolution set in the context of a hierarchical scenario for structure formation. The models predict a scatter in the luminosities of the BCGs that is somewhat larger than the observed one, but that depends on the criterion used to select the model clusters.

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A. Aragon-Salamanca, C. M. Baugh, G. Kauffmann. 1998-01-28. The K-band Hubble diagram for the brightest cluster galaxies: a test of hierarchical galaxy formation models. https://doi.org/10.1046/j.1365-8711.1998.01495.x

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