Relativistic Positron-Electron-Ion Shear Flows and Application to Gamma-Ray Bursts

We present Particle-in-Cell simulation results of relativistic shear flows for hybrid positron-electron-ion plasmas and compare to those for pure e+e- and pure e-ion plasmas. Among the three types of relativistic shear flows, we find that only hybrid shear flow is able to energize the electrons to form a high-energy spectral peak plus a hard power-law tail. Such electron spectra are needed to model the observational properties of gamma-ray bursts.

Comments: 18 pages, 5 figures. Paper accepted by APJL

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