Constraining the efficiency of cosmic ray acceleration by cluster shocks

  title={Constraining the efficiency of cosmic ray acceleration by cluster shocks},
  author={Franco Vazza and Marcus Brueggen and Denis Wittor and Claudio Gheller and Dominique Eckert and Matthew Lynn Stubbe},
  journal={Monthly Notices of the Royal Astronomical Society},
We study the acceleration of cosmic rays by collisionless structure formation shocks with ENZO grid simulations. Data from the FERMI satellite enable the use of galaxy clusters as a testbed for particle acceleration models. Based on advanced cosmological simulations that include different prescriptions for gas and cosmic rays physics, we use the predicted {\gamma}-ray emission to constrain the shock acceleration efficiency. We infer that the efficiency must be on average <0.1% for cosmic shocks… 

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