Reconciling observed gamma-ray burst prompt spectra with synchrotron radiation?

  title={Reconciling observed gamma-ray burst prompt spectra with synchrotron radiation?},
  author={Fr'ed'eric Daigne and Ž. Bo{\vs}njak and G. Dubus Institut d'Astrophysique de Paris and UMR7095 Cnrs and Aim IrfuService d'Astrophysique and Laboratoire d'Astrophysique de Grenoble and Umr 5571 Universit'e Joseph Fourier-CNRS},
  journal={Astronomy and Astrophysics},
Context. Gamma-ray burst emission in the prompt phase is often interpreted as synchrotron radiation from high-energy electrons accelerated in internal shocks. Fast synchrotron cooling of a power-law distribution of electrons leads to the prediction that the slope below the spectral peak has a photon index α = −3/ 2( N(E) ∝ E α ). However, this differs significantly from the observed median value α ≈− 1. This discrepancy has been used to argue against this scenario. Aims. We quantify the… 
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