Cooling flows or warming rays

  title={Cooling flows or warming rays},
  author={Sergio Colafrancesco and Arnon Dar and Alvaro De R{\'u}jula},
  journal={Astronomy and Astrophysics},
The radiative cooling time of the X-ray-emitting plasma near the center in many clusters of galaxies is shorter than the age of the cluster, but neither the expected large drop in central temperature - nor the expected mass flow towards the pressure-depleted cluster centers - are observed. We propose a solution to these "cooling flow" problems wherein energy is supplied to the plasma by hadronic cosmic rays (CRs). The solution requires an energy deposition more intense and more distributed than… 

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will be inserted by hand later ) Cooling Flows or Warming Rays ?
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