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Radio galaxy feedback in X-ray selected groups from COSMOS: the effect on the ICM

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 نشر من قبل Stefania Giodini
 تاريخ النشر 2010
  مجال البحث فيزياء
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We quantify the importance of the mechanical energy released by radio-galaxies inside galaxy groups. We use scaling relations to estimate the mechanical energy released by 16 radio-AGN located inside X-ray detected galaxy groups in the COSMOS field. By comparing this energy output to the host groups gravitational binding energy, we find that radio galaxies produce sufficient energy to unbind a significant fraction of the intra-group medium. This unbinding effect is negligible in massive galaxy clusters with deeper potential wells. Our results correctly reproduce the breaking of self-similarity observed in the scaling relation between entropy and temperature for galaxy groups.



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