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The impact of cooling flows on the Tx-Lbol relation for the most luminous clusters

S. W. Allen·A. C. Fabian
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Abstract

We examine the effects of cooling flows on the T_X-L_Bol relation for a sample of the most X-ray luminous (L_Bol > 10^45 erg/s) clusters of galaxies known. Using high-quality ASCA X-ray spectra and ROSAT images we explicitly account for the effects of cooling flows on the X-ray properties of the clusters and show that this reduces the previously-noted dispersion in the T_X-L_Bol relationship. More importantly, the slope of the relationship is flattened from L_Bol \propto T_{X}^3 to approximately L_Bol\propto T_{X}^2, in agreement with recent theoretical models which include the effects of shocks and preheating on the X-ray gas. We find no evidence for evolution in the T_X-L_Bol relation within z~0.3. Our results demonstrate that the effects of cooling flows must be accounted for before cosmological parameters can be determined from X-ray observations of clusters. The results presented here should provide a reliable basis for modelling the T_X-L_Bol relation at high X-ray luminosities.

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S. W. Allen, A. C. Fabian. 1998-03-01. The impact of cooling flows on the Tx-Lbol relation for the most luminous clusters. https://doi.org/10.1046/j.1365-8711.1998.01737.x

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