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arXiv · 1902.01768

On the generalized Faber-Jackson relation for galaxy clusters

Carlos E. Navia
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Abstract

The significant deviations among observations and the expectations based on self-similar scaling model of galaxy clusters, especially up to redshift $z\lesssim 0.4$, constrain the evolution of the X-ray clusters scaling relations with the redshift, is claimed that in this redshift range, the data has a strong influence by selection bias. However, also suggests that some non-gravitational processes can be responsible for a weak or almost null evolution, at least to $z\lesssim 0.4$. This almost universality observed in X-ray galaxy clusters can be understood if we assume that the X-ray emission, results from thermal bremsstrahlung from a hot diffuse intracluster gas with temperatures about $10^8$ K. A fraction of it would not be bound to the cluster and would escape as a wind. This hot wind can warm the local environment, the thermal bath where the cluster is immersed. This mechanism can put all the galaxy clusters within thermal baths, with almost the same effective temperature, independent of the cluster redshift and it can be effective for clusters with redshifts up to $z\sim 0.4$. Debye Gravitational Theory (DGT), allows obtaining a Generalized Faber-Jackson relation to described the galaxy clusters such as the M-$σ$ and M-Tx relations as a function of the bath thermal temperature. We show that the DGT prediction to the M-$σ$ relation, overlap the fit on data of an extensive spectroscopic survey of galaxy clusters with MMT/Hectospec, at 0.1$\leq$ z $\leq$ 0.3. And the DGT predictions to the M-Tx relation almost overlap the fit on data from Canada France Hawaii Telescope Lensing Survey and XMM-CFHTLS surveys up to $z\sim 0.47$.

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Carlos E. Navia. 2019-02-05. On the generalized Faber-Jackson relation for galaxy clusters. https://arxiv.org/abs/1902.01768

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