Yilmaz Mehmet Fatih, Danisman Yusuf, Larour Jean, Arantchouk Leonid
Basic Sciences, Engineering Department, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia.
Department of Mathematics and Computer Science, Queensborough Community College CUNY, New York City, NY, USA.
Sci Rep. 2019 Aug 14;9(1):11867. doi: 10.1038/s41598-019-47997-6.
In this study, Linear Discriminant Analysis (LDA) is applied to investigate the electron beam effects on the X-pinch produced K-shell Aluminum plasma. The radiating plasma is produced by the explosion of two 25-μm Al wires on a compact L-C (40 kV, 200 kA and 200 ns) generator, and the time integrated spectra are recorded using de Broglie spectrographs. The ion and electron oscillations of K-shell Al plasma are extracted using LDA of spectral database of non-LTE K-shell Al model. A three dimensional representation of LDA shows that the presence of electron beam exhibits outward spirals of Langmuir turbulence and the center region of the spirals recieves lower electron temperatures of 50-100 eV. These spirals then are modeled by logistic growth of predator-prey model. This modeling suggests that the ions (LD1: most dominant eigenvector of LDA) and electrons (LD2: second most dominant eigenvector of LDA) represent the predators and preys, respectively. Besides, addition of electron beams transforms evanescent oscillations to the standing ones.
在本研究中,应用线性判别分析(LDA)来研究电子束对X箍缩产生的K壳层铝等离子体的影响。辐射等离子体由两根25μm的铝丝在紧凑的L-C(40kV、200kA和200ns)发生器上爆炸产生,并用德布罗意光谱仪记录时间积分光谱。利用非局部热动平衡K壳层铝模型的光谱数据库的LDA提取K壳层铝等离子体的离子和电子振荡。LDA的三维表示表明,电子束的存在呈现出朗缪尔湍流的向外螺旋,螺旋的中心区域接收50-100eV的较低电子温度。然后,这些螺旋由捕食者-猎物模型的逻辑增长来建模。该建模表明,离子(LD1:LDA的最主要特征向量)和电子(LD2:LDA的第二主要特征向量)分别代表捕食者和猎物。此外,电子束的加入将瞬逝振荡转变为驻波振荡。