Kinematic analysis of a sample of X-ray luminous distant galaxy clusters The L-x-sigma(v) relation in the z > 0.6 universe
Abstract
Aims. Observations and cosmological simulations show galaxy clusters as a family of nearly self-similar objects with properties that can be described by scaling relations as a function of mass and time. Here we study the scaling relations between the galaxy velocity dispersion (sigma(v)) and X-ray quantities, such as X-ray bolometric luminosity (L-X,500(Bol)) and temperature (T-X) in galaxy clusters at high redshifts (0.64 <= z <= 1.46). We also compare our results with the analogous study of the local HIFLUGCS sample. Methods. For the analysis, we use a set of 15 distant galaxy clusters extracted from the literature and selected via different methods. We also use a sample of ten newly discovered clusters selected via their X-ray emission by the XMM-Newton Distant Cluster Project (XDCP), with more than ten confirmed spectroscopic members per cluster. For both samples, the same method was used to determine sigma(v). We also study the evolution of this scaling relation by comparing the high redshift results with the data from the HIFLUGCS sample, which is taken as a representative of the conditions in the local Universe. For such an analysis, we restrict the study to the clusters in the common L-X,500(Bol) range. We also investigate the L-X - T-X and the sigma(v) - T-X relations for the 15 clusters from the literature sample. Results. We report the results of the X-ray and kinematic analysis of ten newly detected high redshift clusters and provide their spectroscopic and kinematic details. For the entire distant sample, we find a slope fully consistent with the one typical of local clusters, albeit with a large associated uncertainty (similar to 26%). We repeat the tit by freezing the slope to the value found for the HIFLUGCS systems restricted to the same luminosity range as our sample to investigate the evolution of the amplitude alone. We find a positive offset of Delta A/A = 0.44 +/- 0.22 if the self-similar evolution is neglected, hence indicating the possible need for including evolutionary effects. However, the L-X - T-X relation is found to be in good agreement with the local relation without any significant redshift evolution. Finally, the sigma(v) - T-X relation appears to slightly deviate from the theoretical expectation that galaxies and gas particles have a similar specific kinetic energy. However, the associated uncertainty is currently too large for making any conclusive statement in this regard.
Más información
Título según WOS: | Kinematic analysis of a sample of X-ray luminous distant galaxy clusters The L-x-sigma(v) relation in the z > 0.6 universe |
Título según SCOPUS: | Kinematic analysis of a sample of X-ray luminous distant galaxy clusters: The L X-? v relation in the z > 0.6 universe |
Título de la Revista: | ASTRONOMY & ASTROPHYSICS |
Volumen: | 564 |
Editorial: | EDP SCIENCES S A |
Fecha de publicación: | 2014 |
Idioma: | English |
DOI: |
10.1051/0004-6361/201322321 |
Notas: | ISI, SCOPUS |