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Abstract: Abridged We present an analysis of the scaling relations between X-rayproperties and Sunyaev-Zeldovich SZ parameters for a sample of 24 X-rayluminous galaxy clusters observed with Chandra and with measured SZ effect.These objects are in the redshift range 0.14-0.82 and have X-ray bolometricluminosity L>10^45 erg-s. We perform a spatially resolved spectral analysis andrecover the density, temperature and pressure profiles of the ICM, just relyingon the spherical symmetry of the cluster and the hydrostatic equilibriumhypothesis. We observe that the correlations among X-ray quantities only are inagreement with previous results obtained for samples of high-z X-ray luminousgalaxy clusters. On the relations involving SZ quantities, we obtain that theycorrelate with the gas temperature with a logarithmic slope significantlylarger than the predicted value from the self-similar model. The measuredscatter indicates, however, that the central Compton parameter y 0 is a proxyof the gas temperature at the same level of other X-ray quantities likeluminosity. Our results on the X-ray and SZ scaling relations show a tensionbetween the quantities more related to the global energy of the system e.g.gas temperature, gravitating mass and the indicators of the structure of theICM e.g. gas density profile, central Compton parameter y 0, showing the mostsignificant deviations from the values of the slope predicted from theself-similar model in the L-T, L-M {tot}, M {gas}-T, y 0-T relations. When theslope is fixed to the self-similar value, these relations consistently show anegative evolution suggesting a scenario in which the ICM at higher redshifthas lower both X-ray luminosity and pressure in the central regions than theexpectations from self-similar model.



Autor: A. Morandi, S. Ettori, L. Moscardini

Fuente: https://arxiv.org/







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