Diagnostics of recombining laser plasma parameters based on He-like ion resonance lines intensity ratios

31st International Conference on Equations of State for Matter

Ryazantsev, S.N.^1 ; Skobelev, I.Yu.^1 ; Faenov, A.Ya.^1 ; Pikuz, T.A.^1 ; Grum-Grzhimailo, A.N.^1,2 ; Pikuz, S.A.^1

Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya 13 Bldg 2, Moscow

125412, Russia^1

Skobeltsyn Institute for Nuclear Physics, Lomonosov Moscow State University, Leninskiye Gory 1, Moscow

119899, Russia^2

关键词: Astrophysical phenomena;    Diagnostic methods;    Hydrodynamic equations;    Laboratory astrophysics;    Recombining plasmas;    Relative intensity;    Resonance transition;    Young stellar objects;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/774/1/012116/pdf
DOI  :  10.1088/1742-6596/774/1/012116

来源: IOP

【 摘 要 】

While the plasma created by powerful laser expands from the target surface it becomes overcooled, i.e. recombining one. Improving of diagnostic methods applicable for such plasma is rather important problem in laboratory astrophysics nowadays because laser produced jets are fully scalable to young stellar objects. Such scaling is possible because of the plasma hydrodynamic equations invariance under some transformations. In this paper it is shown that relative intensities of the resonance transitions in He-like ions can be used to measure the parameters of recombining plasma. Intensity of the spectral lines corresponding to these transitions is sensitive to the density in the range of 1016-1020cm-3while the temperature ranges from 10 to 100 eV for ions with nuclear charge Zn∼ 10. Calculations were carried out for F VIII ion and allowed to determine parameters of plasma jets created by nanosecond laser system ELFIE (Ecole Polytechnique, France) for astrophysical phenomenon modelling. Obtained dependencies are quite universal and can be used for any recombining plasma containing He-like fluorine ions.