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arXiv · 0805.3024

Coherent forward stimulated Brillouin scattering of a spatially incoherent laser beam in a plasma and its effect on beam spray

M. Grech·G. Riazuelo·D. Pesme·S. Weber·V. T. Tikhonchuk
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Abstract

A statistical model for forward stimulated Brillouin scattering (FSBS) is developed for a spatially incoherent, monochromatic, laser beam propagating in a plasma. A threshold for the average power in a speckle is found, well below the self-focusing one, above which the laser beam spatial incoherence can not prevent the coherent growth of FSBS. Three-dimensional simulations confirm its existence and reveal the onset of beam spray above it. From these results, we propose a new figure of merit for the control of the propagation through a plasma of a spatially incoherent laser beam.

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M. Grech, G. Riazuelo, D. Pesme, S. Weber, V. T. Tikhonchuk. 2008-05-20. Coherent forward stimulated Brillouin scattering of a spatially incoherent laser beam in a plasma and its effect on beam spray. https://doi.org/10.1103/physrevlett.102.155001

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