The electromagnetic sky-map radiated by the Kelvin-Helmholtz instability

We present angularly resolved spectra from a Kelvin-Helmholtz instability (KHI) simulated at an unprecedented spatial, spectral and angular resolution.
This KHI simulated is a model of those KHIs expected to occur in active galactic nuclei and the afterglow of gamma-ray bursts. Our 3D, fully relativistic particle-in-cell simulation is initialized with two neighboring, counter-propagating plasma streams with initially sharp surfaces. During the simulation, a relativistic KHI extending over 9 vortices at an unprecedented resolution of 0.06 classical skin depths developed. The strong magnetic fields occurring in the KHI are a possible mechanism behind the non-thermal electromagnetic emissions from gamma-ray bursts. By simulating the far field radiation of this collisionless plasma shock using Liénard-Wiechert potentials, we obtained spectra for one quarter of the full sky map. Unique radiation signatures were linked to the particle dynamics during the formation of the relativistic, fully-3D KHI.