Positron-Impact Excitation of Hydrogen Atoms in Debye Plasmas
ZHANG Song-Bin1, QI Yue-Ying2,3, QU Yi-Zhi4, CHEN Xiang-Jun1, WANG Jian-Guo2
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 2300262Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, PO Box 8009, Beijing 1000883School of Electrical Engineering, Jiaxing University, Jiaxing 3140014College of Material Sciences and Optoelectronic Technology, Graduate school of the Chinese Academy of Sciences, PO Box 4588, Beijing 100049
Positron-Impact Excitation of Hydrogen Atoms in Debye Plasmas
ZHANG Song-Bin1, QI Yue-Ying2,3, QU Yi-Zhi4, CHEN Xiang-Jun1, WANG Jian-Guo2
1Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 2300262Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, PO Box 8009, Beijing 1000883School of Electrical Engineering, Jiaxing University, Jiaxing 3140014College of Material Sciences and Optoelectronic Technology, Graduate school of the Chinese Academy of Sciences, PO Box 4588, Beijing 100049
摘要The positron-impact excitation of hydrogen atoms embedded in plasma environments is investigated using the close-coupling approximation from the low to intermediate energy region without including any positronium formation channel, and the excitation cross sections for 1s→2s, 1s→2p and 2s→2p processes are calculated in a wide Debye parameter range. The screening interactions, described by the Debye-Hückel model, decrease the coupling matrix elements, resulting in the reduction of the excitation cross sections from a few percent to one magnitude of ten. This will alter remarkably the spectroscopy of hydrogen in intensity and position, which should be considered in the simulation and diagnostics under some specific plasma conditions.
Abstract：The positron-impact excitation of hydrogen atoms embedded in plasma environments is investigated using the close-coupling approximation from the low to intermediate energy region without including any positronium formation channel, and the excitation cross sections for 1s→2s, 1s→2p and 2s→2p processes are calculated in a wide Debye parameter range. The screening interactions, described by the Debye-Hückel model, decrease the coupling matrix elements, resulting in the reduction of the excitation cross sections from a few percent to one magnitude of ten. This will alter remarkably the spectroscopy of hydrogen in intensity and position, which should be considered in the simulation and diagnostics under some specific plasma conditions.
[1] Salzman D 1998 Atomic Physics in Hot Plasmas(Oxford: Oxford University) [2] Murillo M S and Weisheit J C 1998 Phys. Rep. 302 1 [3] Woltz L A et al 1982 J. Quant. Spectrosc. Radiat. Transfer 27 233 Richard M M 1982 J. Quant. Spectrosc. Radiat. Transfer 27 345 [4] Rostas W F 1985 Spectral Line Shapes (New York:Walter de Gruyter) vol 3 p 181 [5] Vinogradov A V et al 1976 Sov. Phys. JETP 44542 [6] Whitten B L et al 1984 Phys. Rev. A 29 945 Whitten B L et al 1984 Phys. Rev. A 30 650 [7] Yuan J K et al 1996 J. Phys. B 29 153 [8] Jung Y -D 1995 Phys. Plasmas 2 332 Jung Y -D 1995 Phys. Plasmas 2 1775 [9] Jung Y -D 1997 Phys. Plasmas 4 21 [10] Qi Y Y et al 2009 Phys. Plasmas 16 023502 [11] Jung Y -D and Yoon J -S 1996 J. Phys. B 293549 [12] Rasolt M and Perrot F 1989 Phys. Rev. Lett 622273 [13] Sabyasachi Kar and Ho Y K 2005 J. Phys. B 383299 [14] Morgan L A 1982 J. Phys. B 15 L25 [15] Higgins K et al 1990 J. Phys. B 23 1345 [16] Bray and Stelbovics 1994 Phys. Rev. A 49R2224 [17] Gien T T 1997 J. Phys. B 30 L23 [18] Kernoghany A A et al 1996 J. Phys. B 29 2089 [19] Mitroy J 1993 Aust. J. Phys. 46 751 [20] Mitroy J et al 1994 Phys. Rev. Lett. 73 2966 [21] ZHOU Y J et al 1998 Chin. Phys. Lett. 15 180 [22] WU Y et al 2005 Chin. Phys. Lett. 22 861 [23] Percival I C et al 1957 Proc. Cam. Phil. Soc. 53 654 [24] Bartschat K 1995 Computational Atomic Physics(Berlin: Springer) chap 6 [25] Salvat F et al 1995 Comput. Phys. Commun. 90151 [26] Chandra N 1973 Comput. Phys. Commun. 5 417 [27] Qi Y Y et al 2008 Phys. Rev. A 78 062511 [28] Nantel M et al 1998 Phys. Rev. Lett. 80 4442
2010, Vol. 27 
