镁和铝样品特征等离子体的L壳层X射线吸收特性研究
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摘要
激光等离子体所特有的极端物理环境使我们很难用直接的手段获取等离子体状态参数，长期以来，光谱诊断在激光等离子体诊断领域发挥着重要作用。等离子体的发射谱利吸收谱是光谱诊断在实际应用中的两个方面。X射线在介质中被吸收过程主要有三种形式：光电离、光激发、逆轫致吸收，这三种微观过程尤其是光电离和光激发与原子结构密切相关。本工作采用不可分辨跃迁系(UTA)模型对光谱结构进行处理，并发展了计算样品等离子体辐射不透明度的方法。求解Saha方程时考虑了离化势下降修正，并用量子亏损理论(QDT)处理高主量子数组态，从而大大减少了计算量。
在“星光-Ⅱ”激光装置上，选择金为背光源材料、镁和铝为样品材料，分别采用点投影背光法和多层靶面背光法探测样品等离子体的L壳层吸收的特性。实验中观察到镁样品等离子体属于类铍离子的2p~2-2p3d跃迁系、类锂离子的lS~22S-ls~23p跃迁系利类铍离子的2s~2-2s3p跃迁系，以及铝样品等离子体分别属于类锂离子的2s-3p和2p-3d跃迁系、类铍离子的2s~2-2s3p、2s2p-2s3d、2p~2-2p3d跃迁系以及类硼离子的2s~22p-2s~23d跃迁系。
实验中推得镁样品特征等离子体的电子温度在50～60eV之间，物质密度为0．01±0．002g／cm~3，在局域热动平衡情况下我们的理论计算结果与实验符合较好。由理论计算结果与实验的比较，我们还推得铝样品等离子体的电子温度在34eV附近，样品等离子体的离化度分布的理论计算结果与实验观测也相符合。
这些理论利实验数据对于辐射不透明度研究、惯性约束聚变以及X射线激光均有一定的参考价值。
For the typical physics states of the laser plasma, it is difficult to obtain the plasma parameters directly. Spectroscopic diagnostics play an important role in the field of plasma diagnostics. The emission and absorption spectra can be used. The main absorption mechanisms include photoexcitation (bound-bound transition), photoionization (bound-free transition), and inverse bremsstrahlung (free-free transition), which relate to the atomic structre. Based on unresolved transition array model(UTA), we developed a method to calculate the transmission spectra of the sample plasma. The depression of ionization potential (DIP) is considered in solving the Saha-equations, and the quantum effect theory is used to treat the atomic states with high principal quantum numbers..
The L-shell X-ray absorption measurement of Mg and Al sample plasma has been performed on "Xing-Guang II" high power laser facility, in which point projection spectroscopy (pps) techniques and multi-layered target were employed. The gold is chosen as the backlighter for its unique pseudocontinuous spectrum from the O-band emission. The absorption lines of Li-like Is22s-ls23p transition arrays and Be-like 2p2-2p3d 2s2-2s3p transition arrays are clearly observed in experiment I, and the absorption lines of Li-like 2s-3p 2p-3d transition arrays Be-like 2s2-2s3p 2s2p-2s3d 2p2-2p3d transition arrays and the B-like 2s22p-2s23d transition arrays in experiment II.
The electron temperature of Mg sample characteristic plasma is determined 50~60eV, and the mass density 0.01?.002g/cm3. In local thermodynamic equilibrium(LTE), the predicted transmission spectrum is calculated and the calculation results are in agreement with the experiment. With the comparison between the calculations and experimental results in experiment II, we infer that the electron temperature of the Al sample plasma is about 34eV.
在“星光-Ⅱ”激光装置上，选择金为背光源材料、镁和铝为样品材料，分别采用点投影背光法和多层靶面背光法探测样品等离子体的L壳层吸收的特性。实验中观察到镁样品等离子体属于类铍离子的2p~2-2p3d跃迁系、类锂离子的lS~22S-ls~23p跃迁系利类铍离子的2s~2-2s3p跃迁系，以及铝样品等离子体分别属于类锂离子的2s-3p和2p-3d跃迁系、类铍离子的2s~2-2s3p、2s2p-2s3d、2p~2-2p3d跃迁系以及类硼离子的2s~22p-2s~23d跃迁系。
实验中推得镁样品特征等离子体的电子温度在50～60eV之间，物质密度为0．01±0．002g／cm~3，在局域热动平衡情况下我们的理论计算结果与实验符合较好。由理论计算结果与实验的比较，我们还推得铝样品等离子体的电子温度在34eV附近，样品等离子体的离化度分布的理论计算结果与实验观测也相符合。
这些理论利实验数据对于辐射不透明度研究、惯性约束聚变以及X射线激光均有一定的参考价值。
For the typical physics states of the laser plasma, it is difficult to obtain the plasma parameters directly. Spectroscopic diagnostics play an important role in the field of plasma diagnostics. The emission and absorption spectra can be used. The main absorption mechanisms include photoexcitation (bound-bound transition), photoionization (bound-free transition), and inverse bremsstrahlung (free-free transition), which relate to the atomic structre. Based on unresolved transition array model(UTA), we developed a method to calculate the transmission spectra of the sample plasma. The depression of ionization potential (DIP) is considered in solving the Saha-equations, and the quantum effect theory is used to treat the atomic states with high principal quantum numbers..
The L-shell X-ray absorption measurement of Mg and Al sample plasma has been performed on "Xing-Guang II" high power laser facility, in which point projection spectroscopy (pps) techniques and multi-layered target were employed. The gold is chosen as the backlighter for its unique pseudocontinuous spectrum from the O-band emission. The absorption lines of Li-like Is22s-ls23p transition arrays and Be-like 2p2-2p3d 2s2-2s3p transition arrays are clearly observed in experiment I, and the absorption lines of Li-like 2s-3p 2p-3d transition arrays Be-like 2s2-2s3p 2s2p-2s3d 2p2-2p3d transition arrays and the B-like 2s22p-2s23d transition arrays in experiment II.
The electron temperature of Mg sample characteristic plasma is determined 50~60eV, and the mass density 0.01?.002g/cm3. In local thermodynamic equilibrium(LTE), the predicted transmission spectrum is calculated and the calculation results are in agreement with the experiment. With the comparison between the calculations and experimental results in experiment II, we infer that the electron temperature of the Al sample plasma is about 34eV.
引文
1．傅依备 杨建国等《惯性约束与强激光技术》1990年《强激光与离子束》杂志社出版；
2．常铁强等《激光等离子态体相互作用与激光聚变》1991年湖南科学技术出版社出版；
3.Yamannka C Laser Plasma and Inertial Confinement Fusion, 1991 Elsevier Science Publishers
4.John Lindl, Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain, UCRL-JC-199015,1995
5.Holtgreven W L Plasma Diagnostics, Interscience Publishers, 1968,New York
6．李世昌 《高温辐射物理与量子辐射理论》,1992年国防工业出版社出版；
7．项志遴 俞昌旋《高温等离子体诊断技术》，1982年上海科学技术出版社出版；
8．孙永盛《辐射不透明度研究现状》
9.Bauche-Arnoult, Bauche J and Klapisch M 1979 Phys Rev A 20 P2424
10.Bauche-Arnoult, Bauche J and Klapisch M 1982 Phys Rev A 25 P2641
11.Bauche-Amoult, Bauche J and Klapisch M 1985 Phys Rev A 31 P2248
12.Kilcrease D P, A bdallah J and Keady J J et al. 1993 J. Phys. B. 26 P717
13.Bar-Shalom A, Oreg J and Goldstein W H et al. 1989 Phys Rev A 40 P3183
14.Lewis C L S and McGlinchey J 1985 Opt. Commun. 53 P179
15.Davison S J, Foster J M, Smith C C and Warburton K A et al 1988 Appl. Phys. Left. 52 P847
16.C.Chenais-Popovics, Fievet C and Geindre J P et a1.1989 Phys Rev A 40 P3194
17.C.Chenais-Popovics et al. 1990 Phys RevA 42, P4788;
18.Burkhalter P G, Mehlman G, Newman D A and Ripin B H 1990 Rev. Sci. Instru. 61 P2741
19.Springer P T, Goldstein W and Hooper C et al. 1991 Word Science P42
20.Silva L.B.Da et al. 1992 Phys. Rev. Lett. 69, P438
21.Adriano F, Tyson T A and Hodgson K O et al 1993 Phys Rev A 48 P 1328
22.Perry T S, Springer P T, Fields D F and Bach D R et al 1996 Phys. Rev. E54 5617
23.Yoshiaki lto, Vlaicu A M and Tochio T et al. 1998 Phys RevA 57,P873;
24.C.Chenais-Popovics et al. Inertial Fusion Sciences and Applications, P1097, 1999;
25．张保汉等人《热稠密物理辐射特性研究》，1998年度技术总结；
26.Griem H R 1964 Plasma Spectroscopy (New York: McGraw-Hill) chap 14 P299
27．张家泰《激光等离子体相互作用物理与模拟》1999年河南科学技术出版社出版；
28.Lee C M and Johnson W R 1980 Phys Rev A 22 P979
29．杨力 赵伊君 张志杰 1988物理学报 37P1341
30.Seaton M J 1966 Proc. Phys. Soc. 88 P801
31.Seaton M J 1966 Proc. Phys. Soc. 88 P815
32.Yan J, Li J M 2000 Chin. Phys. Lett. 17 194
33.Yan J, Qu Y Z and Li JM International Seminar on Atomic Processes in Plasmas Japan July 1999
34．董骐 李家明 1986 物理学报 35 P1634
35．鲍敏琪 仝晓民 李家明 1989 物理学报 38 P1802
36．杨国洪 张继彦 张保汉等人 2000年 物理学报 49 P2389
37.Zhang J Y, Yang X D, Yang G H and Zhang B H et al 2001 Chin. Phys. 10 P809
38.Perry T S, Davison S J, Serduke F J, Bach D R et al 1991 Phys. Rev. Lett. 67 P3784
39．林彬《W高离化度激光等离子体发射的软X射线谱的半连续带状结构研究》1995年中国工程物理研究院硕士学位论文
40.Zeng J L Jin F T and Yuan J M et al 2000 Phys. Rev. E.62 P7251
41.Back C A, Chenais-Popovics C and Lee R W 1991 Phys Rev A 44 P6730
42.Back C A, Castor J I and Klein R I et al. 1991 Phys Rev A 44 P6743
43.Epstein R and Yaakobi 1991 Phys Rev A 44 P5111
44.Liu H J, Zhang B H et al 2002 Chin. Phys. Lett. 19 P362
45.Mochizuki T, Sakabe S and Shiraga H et al. 1983 J. Appl. Phys. 22 P133
46.Mochizuki T, Yabe T and Azechi H et al 1986 Phys Rev A 33 P525
47.Liu H J, Zhang B H et al 2002 Chin. Phys. 10
48.Yang J M, Ding YN and Zhang B H et al 2001 Chin. Phys. Lett. 18 P550
49.Riordan J C and Pearlman J S 1981 Appl. Phys. Lett 39 P543
50.Foster J M, Hoarty D J and Smith C C et al. 1991 Phys. Rev. Lett 67 P3255
51.Oks E 1999 Phys Rev E 60 P2480
2．常铁强等《激光等离子态体相互作用与激光聚变》1991年湖南科学技术出版社出版；
3.Yamannka C Laser Plasma and Inertial Confinement Fusion, 1991 Elsevier Science Publishers
4.John Lindl, Development of the indirect-drive approach to inertial confinement fusion and the target physics basis for ignition and gain, UCRL-JC-199015,1995
5.Holtgreven W L Plasma Diagnostics, Interscience Publishers, 1968,New York
6．李世昌 《高温辐射物理与量子辐射理论》,1992年国防工业出版社出版；
7．项志遴 俞昌旋《高温等离子体诊断技术》，1982年上海科学技术出版社出版；
8．孙永盛《辐射不透明度研究现状》
9.Bauche-Arnoult, Bauche J and Klapisch M 1979 Phys Rev A 20 P2424
10.Bauche-Arnoult, Bauche J and Klapisch M 1982 Phys Rev A 25 P2641
11.Bauche-Amoult, Bauche J and Klapisch M 1985 Phys Rev A 31 P2248
12.Kilcrease D P, A bdallah J and Keady J J et al. 1993 J. Phys. B. 26 P717
13.Bar-Shalom A, Oreg J and Goldstein W H et al. 1989 Phys Rev A 40 P3183
14.Lewis C L S and McGlinchey J 1985 Opt. Commun. 53 P179
15.Davison S J, Foster J M, Smith C C and Warburton K A et al 1988 Appl. Phys. Left. 52 P847
16.C.Chenais-Popovics, Fievet C and Geindre J P et a1.1989 Phys Rev A 40 P3194
17.C.Chenais-Popovics et al. 1990 Phys RevA 42, P4788;
18.Burkhalter P G, Mehlman G, Newman D A and Ripin B H 1990 Rev. Sci. Instru. 61 P2741
19.Springer P T, Goldstein W and Hooper C et al. 1991 Word Science P42
20.Silva L.B.Da et al. 1992 Phys. Rev. Lett. 69, P438
21.Adriano F, Tyson T A and Hodgson K O et al 1993 Phys Rev A 48 P 1328
22.Perry T S, Springer P T, Fields D F and Bach D R et al 1996 Phys. Rev. E54 5617
23.Yoshiaki lto, Vlaicu A M and Tochio T et al. 1998 Phys RevA 57,P873;
24.C.Chenais-Popovics et al. Inertial Fusion Sciences and Applications, P1097, 1999;
25．张保汉等人《热稠密物理辐射特性研究》，1998年度技术总结；
26.Griem H R 1964 Plasma Spectroscopy (New York: McGraw-Hill) chap 14 P299
27．张家泰《激光等离子体相互作用物理与模拟》1999年河南科学技术出版社出版；
28.Lee C M and Johnson W R 1980 Phys Rev A 22 P979
29．杨力 赵伊君 张志杰 1988物理学报 37P1341
30.Seaton M J 1966 Proc. Phys. Soc. 88 P801
31.Seaton M J 1966 Proc. Phys. Soc. 88 P815
32.Yan J, Li J M 2000 Chin. Phys. Lett. 17 194
33.Yan J, Qu Y Z and Li JM International Seminar on Atomic Processes in Plasmas Japan July 1999
34．董骐 李家明 1986 物理学报 35 P1634
35．鲍敏琪 仝晓民 李家明 1989 物理学报 38 P1802
36．杨国洪 张继彦 张保汉等人 2000年 物理学报 49 P2389
37.Zhang J Y, Yang X D, Yang G H and Zhang B H et al 2001 Chin. Phys. 10 P809
38.Perry T S, Davison S J, Serduke F J, Bach D R et al 1991 Phys. Rev. Lett. 67 P3784
39．林彬《W高离化度激光等离子体发射的软X射线谱的半连续带状结构研究》1995年中国工程物理研究院硕士学位论文
40.Zeng J L Jin F T and Yuan J M et al 2000 Phys. Rev. E.62 P7251
41.Back C A, Chenais-Popovics C and Lee R W 1991 Phys Rev A 44 P6730
42.Back C A, Castor J I and Klein R I et al. 1991 Phys Rev A 44 P6743
43.Epstein R and Yaakobi 1991 Phys Rev A 44 P5111
44.Liu H J, Zhang B H et al 2002 Chin. Phys. Lett. 19 P362
45.Mochizuki T, Sakabe S and Shiraga H et al. 1983 J. Appl. Phys. 22 P133
46.Mochizuki T, Yabe T and Azechi H et al 1986 Phys Rev A 33 P525
47.Liu H J, Zhang B H et al 2002 Chin. Phys. 10
48.Yang J M, Ding YN and Zhang B H et al 2001 Chin. Phys. Lett. 18 P550
49.Riordan J C and Pearlman J S 1981 Appl. Phys. Lett 39 P543
50.Foster J M, Hoarty D J and Smith C C et al. 1991 Phys. Rev. Lett 67 P3255
51.Oks E 1999 Phys Rev E 60 P2480