Laser-driven x-ray and neutron source development for industrial applications of plasma accelerators
Laser-driven x-ray and neutron source development for industrial applications of plasma accelerators
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DOI：
10.1088/0741-3335/58/1/014039
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发表时间：
2016-01-01
影响因子：
2.2
通讯作者：
Neely, D.
中科院分区：
文献类型：
--
作者：
Brenner, C. M.;Mirfayzi, S. R.;Neely, D.
强激光与固体箔相互作用产生的高能X射线和中子的脉冲光束在明亮、小发射面积、能够多模传输的理想应用中很有希望。激光驱动多模源的可能最终用户是那些在航空航天、核能和先进制造等高价值商业工业部门需要先进无损检测技术的用户。我们报道了用于产生中子和X射线束的高功率激光-固体相互作用的多模操作的实验工作。测量和蒙特卡罗辐射输运模拟表明，与仅使用2厘米的锂块相比，将1 mm的铜箔放置在2 mm的锂箔后面时，中子产额增加了近2倍。我们探索用10皮秒的驱动脉冲产生X射线，以便为中等密度合金金属的射线照相定制光谱内容。讨论了使用>；1 ps脉冲持续时间对激光加速电子束的产生和传输的影响，以及随后在薄的、高原子序数的靶片中的韧致辐射发射的优化。利用GEANT4蒙特卡罗程序从光谱仪测量和模拟数据中解卷出X射线光谱。我们还展示了激光驱动X射线的独特能力，能够提供厚金属物体的单脉冲高空间分辨率投影成像。首次提出了用10ps的驱动脉冲对工业相关样品物体的主动探测器射线成像，表明在高倍率下投影可以分辨200微米大小的特征。
Pulsed beams of energetic x-rays and neutrons from intense laser interactions with solid foils are promising for applications where bright, small emission area sources, capable of multi-modal delivery are ideal. Possible end users of laser-driven multi-modal sources are those requiring advanced non-destructive inspection techniques in industry sectors of high value commerce such as aerospace, nuclear and advanced manufacturing. We report on experimental work that demonstrates multi-modal operation of high power laser-solid interactions for neutron and x-ray beam generation. Measurements and Monte Carlo radiation transport simulations show that neutron yield is increased by a factor similar to 2 when a 1 mm copper foil is placed behind a 2 mm lithium foil, compared to using a 2 cm block of lithium only. We explore x-ray generation with a 10 picosecond drive pulse in order to tailor the spectral content for radiography with medium density alloy metals. The impact of using >1 ps pulse duration on laser-accelerated electron beam generation and transport is discussed alongside the optimisation of subsequent bremsstrahlung emission in thin, high atomic number target foils. X-ray spectra are deconvolved from spectrometer measurements and simulation data generated using the GEANT4 Monte Carlo code. We also demonstrate the unique capability of laser-driven x-rays in being able to deliver single pulse high spatial resolution projection imaging of thick metallic objects. Active detector radiographic imaging of industrially relevant sample objects with a 10 ps drive pulse is presented for the first time, demonstrating that features of 200 mu m size are resolved when projected at high magnification.