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arXiv · 2110.12639

Spatial profile of accelerated electrons from ponderomotive scattering in hydrogen cluster targets

B. Aurand·L. Reichwein·K. M. Schwind·E. Aktan·M. Cerchez·V. Kaymak·L. Lessmann·R. Prasad·J. Thomas·T. Toncian·A. Khoukaz·A. Pukhov·O. Willi
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Abstract

We study the laser-driven acceleration of electrons from overdense hydrogen clusters to energies of up to 13 MeV in laser forward direction and several hundreds of keV in an outer ring-like structure. The use of cryogenic hydrogen allows for high repetition-rate operation and examination of the influence of source parameters like temperature and gas flow. The outer ring-like structure of accelerated electrons, originating from the interaction, that is robust against the change of laser and target parameters can be observed for low electron densities of ca. 3$\times$10$^{16}$ cm$^{-3}$. For higher electron densities, an additional central spot of electrons in the laser forward direction can be observed. Utilizing 3D-PIC simulations, it is revealed that both electron populations mainly stem from ponderomotive scattering.

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B. Aurand, L. Reichwein, K. M. Schwind, E. Aktan, M. Cerchez, V. Kaymak, L. Lessmann, R. Prasad, J. Thomas, T. Toncian, A. Khoukaz, A. Pukhov, O. Willi. 2021-10-25. Spatial profile of accelerated electrons from ponderomotive scattering in hydrogen cluster targets. https://doi.org/10.1088/1367-2630%2Fac53ba

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