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arXiv · 1304.6203

Laser ion acceleration by using the dynamic motion of a target

Toshimasa Morita
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Abstract

Proton acceleration by using a 620-TW, 18-J laser pulse of peak intensity of $5\times 10^{21}$ W/cm$^{2}$ irradiating a disk target is examined using three-dimensional particle-in-cell simulations. It is shown that protons are accelerated efficiently to high energy for a "light" material in the first layer of a double-layer target, because a strongly inhomogeneous expansion of the first layer occurs by a Coulomb explosion within such a material. Moreover, a large movement of the first layer for the accelerated protons is produced by radiation-pressure-dominant acceleration. A time-varying electric potential produced by this expanding and moving ion cloud accelerates protons effectively. In addition, using the best material for the target, one can generate a proton beam with an energy of 200 MeV and an energy spread of 2$%$.

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Toshimasa Morita. 2013-04-23. Laser ion acceleration by using the dynamic motion of a target. https://doi.org/10.1063/1.4821031

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