Site Map
Follow us on Facebook Follow us on Twitter YouTube channel
Centro de Astrofísica da Universidade do Porto

Galaxies in X-ray Selected Clusters and Groups in Dark Energy Survey Data I: Stellar Mass Growth of Bright Central Galaxies Since z~1.2

Y.-Y. Zhang, C. J. Miller, Timothy A. McKay, P. J. Rooney, A. E. Evrard, A. K. Romer, R. Perfecto, J. Song, S. Desai, J. J. Mohr, H. Wilcox, A. Bermeo, T. Jeltema, D. Hollowood, D. Bacon, D. Capozzi, C. A. Collins, R. Das, D. Gerdes, C. Hennig, M. Hilton, B. Hoyle, S. T. Kay, A. Liddle, R. Mann, N. Mehrtens, R. C. Nichol, C. Papovich, M. Soares-Santos, J. P. Stott, P. T. P. Viana, T. M. C. Abbott, F. B. Abdalla, M. Banerji, A.H. Bauer, A. Benoit-Levy, E. Bertin, D. H. Brooks, E. Buckley-Geer, D. L. Burke, A. C. Rosell, F. J. Castander, H. T. Diehl, P. Doel, C. E. Cunha, T. F. Eifler, A. Fausti Neto, E. Fernandez, B. Flaugher, P. Fosalba, J. A. Frieman, E. Gaztanaga, D. Gruen, R. A. Gruendl, K. Honscheid, D. James, K. Kuehn, N. Kuropatkin, O. Lahav, M. A. G. Maia, M. Makler, J. L. Marshall, P. Martini, R. Miquel, R. Ogando, A. A. Plazas, A. Roodman, E. S. Rykoff, M. Sako, E. Sanchez, V. Scarpine, M. Schubnell, I. Sevilla, R. C. Smith, F. Sobreira, E. Suchyta, M. E. C. Swanson, G. Tarle, J. Thaler, D. L. Tucker, V. Vikram,

Using the science verification data of the Dark Energy Survey (DES) for a new sample of 106 X-Ray selected clusters and groups, we study the stellar mass growth of Bright Central Galaxies (BCGs) since redshift 1.2. Compared with the expectation in a semi-analytical model applied to the Millennium Simulation, the observed BCGs become under-massive/under-luminous with decreasing redshift. We incorporate the uncertainties associated with cluster mass, redshift, and BCG stellar mass measurements into analysis of a redshift-dependent BCG-cluster mass relation, m∗∝(M2001.5×1014M⊙)0.24±0.08(1+z)−0.19±0.34, and compare the observed relation to the model prediction. We estimate the average growth rate since z=1.0 for BCGs hosted by clusters of M200,z=1013.8M⊙, at z=1.0: m∗,BCG appears to have grown by 0.13±0.11 dex, in tension at ∼2.5σ significance level with the 0.40 dex growth rate expected from the semi-analytic model. We show that the buildup of extended intra-cluster light after z=1.0 may alleviate this tension in BCG growth rates.

Acta Astronautica
December 2015

Institute of Astrophysics and Space Sciences

Institute of Astrophysics and Space Sciences (IA) is a new but long anticipated research infrastructure with a national dimension. It embodies a bold but feasible vision for the development of Astronomy, Astrophysics and Space Sciences in Portugal, taking full advantage and fully realizing the potential created by the national membership of the European Space Agency (ESA) and the European Southern Observatory (ESO). IA resulted from the merging the two most prominent research units in the field in Portugal: the Centre for Astrophysics of the University of Porto (CAUP) and the Center for Astronomy and Astrophysics of the University of Lisbon (CAAUL). It currently hosts more than two-thirds of all active researchers working in Space Sciences in Portugal, and is responsible for an even greater fraction of the national productivity in international ISI journals in the area of Space Sciences. This is the scientific area with the highest relative impact factor (1.65 times above the international average) and the field with the highest average number of citations per article for Portugal.

Proceed on CAUP's website|Go to IA website