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arXiv · 1504.07148

Scaling the Yield of Laser-Driven Electron-Positron Jets to Laboratory Astrophysical Applications

Hui Chen·F. Fiuza·A. Link·A. Hazi·M. Hill·D. Hoarty·S. James·S. Kerr·D. D. Meyerhofer·J. Myatt·J. Park·Y. Sentoku·G. J. Williams
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Abstract

We report new experimental results obtained on three different laser facilities that show directed laser-driven relativistic electron-positron jets with up to 30 times larger yields than previously obtained and a quadratic (~ E^2) dependence of the positron yield on the laser energy. This favorable scaling stems from a combination of higher energy electrons due to increased laser intensity and the recirculation of MeV electrons in the mm-thick target. Based on this scaling, first principles simulations predict the possibility of using such electron-positron jets, produced at upcoming high-energy laser facilities, to probe the physics of relativistic collisionless shocks in the laboratory.

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Hui Chen, F. Fiuza, A. Link, A. Hazi, M. Hill, D. Hoarty, S. James, S. Kerr, D. D. Meyerhofer, J. Myatt, J. Park, Y. Sentoku, G. J. Williams. 2015-04-27. Scaling the Yield of Laser-Driven Electron-Positron Jets to Laboratory Astrophysical Applications. https://doi.org/10.1103/physrevlett.114.215001

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