Constraining the magnetic field in GRB relativistic collisionless shocks using radio data

  title={Constraining the magnetic field in GRB relativistic collisionless shocks using radio data},
  author={Rodolfo Barniol Duran},
  journal={Monthly Notices of the Royal Astronomical Society},
  • R. Duran
  • Published 5 November 2013
  • Physics
  • Monthly Notices of the Royal Astronomical Society
Using GRB radio afterglow observations, we calculate the fraction of shocked plasma energy in the magnetic field in relativistic collisionless shocks ($\epsilon_B$). We obtained $\epsilon_B$ for 38 bursts by assuming that the radio afterglow light curve originates in the external forward shock and that its peak at a few to tens of days is due to the passage of the minimum (injection) frequency through the radio band. This allows for the determination of the peak synchrotron flux of the external… 

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