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arXiv · 1402.5226

Approach towards quasi-monoenergetic laser ion acceleration with doped target

Toshimasa Morita
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Abstract

Ion acceleration by using a laser pulse irradiating a disk target which includes hydrogen and carbon is examined using three-dimensional particle-in-cell simulations. It is shown that over $200$ MeV protons can be generated by using a $620$TW, $5\times10^{21}$ W/cm$^2$ laser pulse. In a polyethylene (CH$_2$) target, protons and carbon ions separate and form two layers by radiation pressure acceleration. A strong Coulomb explosion in this situation and Coulomb repulsion between each layer generates high energy protons. A doped target, low density hydrogen within a carbon disk, becomes a double layer target which is comprised of a thin and low density hydrogen disk on the surface of a high-$Z$ atom layer. This then generates a quasi-monoenergetic proton beam.

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Toshimasa Morita. 2014-02-21. Approach towards quasi-monoenergetic laser ion acceleration with doped target. https://doi.org/10.1063/1.4876759

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