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arXiv · 1611.03123

Nonlinear Frequency Shift in Raman Backscattering and its Implications for Plasma Diagnostics

D. Kaganovich·B. Hafizi·J. P. Palastro·A. Ting·M. H. Helle·Y. -H. Chen·T. G. Jones·D. F. Gordon
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Abstract

Raman backscattered radiation of intense laser pulses in plasma is investigated for a wide range of intensities relevant to laser wakefield acceleration. The weakly nonlinear dispersion relation for Raman backscattering predicts an intensity and density dependent frequency shift that is opposite to that suggested by a simple relativistic consideration. This observation has been benchmarked against experimental results, providing a novel diagnostic for laser-plasma interactions.

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D. Kaganovich, B. Hafizi, J. P. Palastro, A. Ting, M. H. Helle, Y. -H. Chen, T. G. Jones, D. F. Gordon. 2016-11-09. Nonlinear Frequency Shift in Raman Backscattering and its Implications for Plasma Diagnostics. https://doi.org/10.1063/1.4971236

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