Accounting for speckle scale beam-bending in classical ray tracing schemes for propagating realistic pulses in indirect drive ignition conditions

C. Ruyer; P. Loiseau; G. Riazuelo; R. Riquier; A. Debayle; P. E. Masson-Laborde

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arXiv · 2209.01035

Accounting for speckle scale beam-bending in classical ray tracing schemes for propagating realistic pulses in indirect drive ignition conditions

C. Ruyer·P. Loiseau·G. Riazuelo·R. Riquier·A. Debayle·P. E. Masson-Laborde

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Abstract

We propose a semi-analytical modeling of smoothed laser beams deviation induced by plasma flows. Based on a Gaussian description of speckles, the model includes spatial, temporal and polarization smoothing techniques,through fits issued from hydrodynamic simulations with a paraxial description of electromagnetic waves. This beam bending model is then included in a ray tracing algorithm, and carefully validated. When applied as a post-process to the propagation of the inner cone in a full-scale simulation of a NIF experiment,the beam bending along the path of the laser affects the refraction conditions inside the hohlraum and the energy deposition, and could explain the anomalous refraction measurements, the so-called glint observed in some NIF experiments.

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BibTeX RIS

C. Ruyer, P. Loiseau, G. Riazuelo, R. Riquier, A. Debayle, P. E. Masson-Laborde. 2022-09-02. Accounting for speckle scale beam-bending in classical ray tracing schemes for propagating realistic pulses in indirect drive ignition conditions. https://arxiv.org/abs/2209.01035

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