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arXiv · 2412.02485

Controlling the interaction of tightly focused 10-PW class lasers with multicomponent plasma via target parameters: optimization of electron-positron pair and $\gamma$-photon sources

A. V. Bashinov·E. S. Efimenko·A. A. Muraviev·E. A. Panova·V. D. Volokitin·I. B. Meyerov·A. V. Kim
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Abstract

The interaction of multipetawatt lasers with plasma is a complex multiparameter problem, providing a wide field for fundamental research and opening up great opportunities for creating unique sources of high-energy electrons and positrons, dense pair plasma, and $\gamma$-photons. However, to achieve high efficiency of such a source, it is necessary to use targets with optimized parameters, primarily density and size, for the given laser parameters. With the use of 3D QED-PIC modeling it is shown that, when targets whose size is comparable with the laser wavelength are irradiated by laser beams with a total power of several tens of PW, the total initial number of target electrons may be regarded to be the similarity parameter of laser-plasma interaction. In practice, this can significantly simplify the selection of the targets needed for controlling the interaction and, accordingly, for achieving the specified parameters of the developed electron-positron plasma and $\gamma$-photon sources. Based on the similarity parameter, various laser-plasma interaction modes are identified, the necessary conditions for their launch are determined, and the properties of the pair particle and $\gamma$-photon source are revealed. Moreover, qualitative estimates of the quantitative and energy characteristics of such a source are obtained, allowing it to be optimized for various laser beam configurations.

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A. V. Bashinov, E. S. Efimenko, A. A. Muraviev, E. A. Panova, V. D. Volokitin, I. B. Meyerov, A. V. Kim. 2024-12-03. Controlling the interaction of tightly focused 10-PW class lasers with multicomponent plasma via target parameters: optimization of electron-positron pair and $\gamma$-photon sources. https://arxiv.org/abs/2412.02485

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