Cool-core condens. rad in massive galaxy clusters

We find that in our our massive cluster sample and in the limited redshift range considered (1.3x10^14^<M500<16.6x10^14^M_{sun}_, 0.03<z<0.29) the distribution of R_ccc_ is peaked at ~0.01r_500_ and entirely included below ~0.07r_500_, with a very weak increase with redshift and no dependence on the cluster mass.We find that Rqcf is typically 3x larger than R_ccc_, has a wider distribution, and grows slowly with R_ccc according to an average relation R_qcf_~~R_ccc_^0.46^, with a large intrinsic scatter.

We suggest that this sub-linear relation can be understood as an effect of the micro rain of pockets of cooled gas flickering in the turbulent ICM, whose dynamical and thermodynamical properties are referred to as "macro weather". Substituting the classical ad-hoc cool-core radius R7.7Gyr, we propose that R_qcf_ is an indicator of the size of global cool cores tied to the long-term macro weather, with the inner R_ccc closely tracing the effective condensation rain and chaotic cold accretion (CCA) zone that feeds the central supermassive black hole (SMBH).