高度离化的钼离子细致结构能谱测量

Measurement of fine structure spectra in high-stripped states laser-produced Mo plasma

高度离化的中、高Z元素激光等离子体辐射的细致结构能谱对惯性约束聚变等离子体诊断和原子结构理论计算等方面非常有用.在"神光II"激光装置上,聚焦0.35μm激光束于真空室内的钼(Mo)元素固体靶上,产生Mo激光等离子体,用高分辨椭圆弯晶谱仪测量Mo激光等离子体辐射在0.32—0.58nm范围内的X射线细致结构能谱,并对实测能谱进行辨识和归类.辨识出了n=4—2,3—2系列离子共振跃迁和内壳层跃迁的能谱线,还有类氢、类氦离子共振线及伴线.另外,对谱线的半高全宽度(FWHM)值做了分析.在整个测量范围内,谱线精确波长值的绝对误差小于0.0005nm,与HFR方法得到的理论计算结果值比较,两者符合较好.此工作的结果对积累Mo元素离子谱线数据具有重要的意义.

The fine structure spectra from very highly stripped ions of the medium and high-Z elements have important applications in plasma diagnostics and the atomic structure calculations. Therefore, on the SG-H laser facility, the X-ray emission spectra from highly stripped plasma of Molybdenum （Mo） are observed by focusing an Nd-glass frequency-tripled （0.35 μm） laser beam onto the surface of the Mo target. The fine structure spectra of Mo ions in a range of 0.32-0.58 nm are measured by a high-resolution elliptically bent crystal spectrometer. Some of resonance transitions and inner-shell transitions of the type 4-2 and 3-2 in the C-like, O-like, F-like and Ne-like iso-electronic sequence and the lines from H-like and He-like Mo ions are identified and classified. In addition, the full widths at half maximum （FWHM） of wavelengths are also analyzed. Wavelengths are measured within an uncertainty of 4-0.0005 nm. A comparison shows that they are in good agreement with computational results of Hartree-Fock-Relativistic （HFR） method. This work is very helpful for enriching the spectra of Mo ions.