The Birmingham-CfA cluster scaling project - III. Entropy and similarity in galaxy systems

  title={The Birmingham-CfA cluster scaling project - III. Entropy and similarity in galaxy systems},
  author={Trevor J. Ponman and Alastair J. R. Sanderson and Alexis Finoguenov},
  journal={Monthly Notices of the Royal Astronomical Society},
We examine profiles and scaling properties of the entropy of the intergalactic gas in a sample of 66 virialized systems, ranging in mass from single elliptical galaxies to rich clusters, for which we have resolved X-ray temperature profiles. Some of the properties we derive appear to be inconsistent with any of the models put forward to explain the breaking of self-similarity in the baryon content of clusters. In particular, the entropy profiles, scaled to the virial radius, are broadly similar… 

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