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arXiv · 1603.04455

Laser Accelerated Ions from a Shock Compressed Gas Foil

M. H. Helle·D. F. Gordon·D. Kaganovich·Y. Chen·J. P. Palastro·A. Ting
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Abstract

We present results of energetic laser-ion acceleration from a tailored, near solid density gas target. Colliding hydrodynamic shocks compress a pure hydrogen gas jet into a 70 μm thick target prior to the arrival of the ultra-intense laser pulse. A density scan reveals the transition from a regime characterized by a wide angle, low energy beam to one of a more focused beam with a high energy halo. In the latter case, three dimensional simulations show the formation of a Z-pinch driven by the axial current resulting from laser wakefield accelerated electrons. Ions at the rear of the target are then accelerated by a combination of space charge fields from accelerated electrons and Coulombic repulsion as the pinch dissipates.

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M. H. Helle, D. F. Gordon, D. Kaganovich, Y. Chen, J. P. Palastro, A. Ting. 2016-03-14. Laser Accelerated Ions from a Shock Compressed Gas Foil. https://doi.org/10.1103/physrevlett.117.165001

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