Efficient energy boost of the laser-accelerated ions is critical for their applications in biomedical and hadron research. Achiev-able energies continue to rise, with currently highest energies, allowing access to medical therapy energy windows. Here, a new regime of simultaneous acceleration of ~100 MeV protons and multi-100 MeV carbon-ions from plasma micro-channel targets is proposed by using a ~1020 W/cm2 modest intensity laser pulse. It is found that two trains of overdense electron bunches are dragged out from the micro-channel and effectively accelerated by the longitudinal electric-field excited in the plasma channel. With the optimized channel size, these “superponderomotive” energetic electrons can be focused on the front surface of the attached plastic substrate. The much intense sheath electric-field is formed on the rear side, leading to up to ~10-fold ionic energy increase compared to the simple planar geometry. The analytical prediction of the optimal channel size and ion maximum energies is derived, which shows good agreement with the particle-in-cell simulations.
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机译:激光加速离子的有效能量提升对其在生物医学和强子研究中的应用至关重要。可获得的能量继续增加,目前能量最高,从而可以进入医学治疗的能量窗口。在这里,提出了一种通过〜10 20 sup> W / cm 2 <同时加速来自等离子体微通道靶的〜100 MeV质子和多-100 MeV碳离子的新机制。 / sup>中等强度的激光脉冲。发现两列过密度的电子束从微通道中被拉出,并被等离子体通道中激发的纵向电场有效地加速。通过优化的通道尺寸,这些“超动力”高能电子可以聚焦在附着的塑料基板的前表面上。在背面形成了非常强烈的鞘层电场,与简单的平面几何形状相比,离子能最多增加约10倍。得出了最佳通道尺寸和离子最大能量的分析预测,这与细胞内颗粒模拟显示出良好的一致性。
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