共查询到20条相似文献,搜索用时 15 毫秒
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Nadir Khan 黄忠魁 汶伟强 Sultan Mahmood 豆丽君 汪书兴 许鑫 汪寒冰 陈重阳 啜晓亚 朱小龙 赵冬梅 冒立军 李杰 殷达钰 杨建成 原有进 朱林繁 马新文 《中国物理C(英文版)》2018,(6)
The accuracy of dielectronic recombination(DR) data for astrophysics related ions plays a key role in astrophysical plasma modeling. The absolute DR rate coefficient of Fe~(17+) ions was measured at the main cooler storage ring at the Institute of Modern Physics, Lanzhou, China. The experimental electron-ion collision energy range covers the first Rydberg series up to n= 24 for the DR resonances associated with the ~2 P_(1/2)→~2 P_(3/2)△n =0 core excitations. A theoretical calculation was performed by using FAC code and compared with the measured DR rate coefficient. Overall reasonable agreement was found between the experimental results and calculations.Moreover, the plasma rate coefficient was deduced from the experimental DR rate coefficient and compared with the available results from the literature. At the low energy range, significant discrepancies were found, and the measured resonances challenge state-of-the-art theory at low collision energies. 相似文献
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Absolute dielectronic recombination rate coefficients of highly charged ions at the storage ring CSRm and CSRe 下载免费PDF全文
黄忠魁 汪书兴 汶伟强 汪寒冰 马万路 陈重阳 张春雨 陈冬阳 黄厚科 邵林 刘鑫 周晓鹏 冒立军 李杰 马晓明 汤梅堂 杨建成 原有进 张少锋 朱林繁 马新文 《中国物理 B》2023,(7):133-142
Dielectronic recombination(DR) is one of the dominant electron–ion recombination mechanisms for most highly charged ions(HCIs) in cosmic plasmas, and thus, it determines the charge state distribution and ionization balance therein.To reliably interpret spectra from cosmic sources and model the astrophysical plasmas, precise DR rate coefficients are required to build up an accurate understanding of the ionization balance of the sources. The main cooler storage ring(CSRm) and the experimental cool... 相似文献
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LaGattuta KJ 《Physical review letters》1988,60(8):692-695
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A. Müller T. Bartsch C. Brandau A. Hoffknecht H. Knopp S. Schippers O. Uwira J. Linkemann A.A. Saghiri M. Schmitt D. Schwalm A. Wolf F. Bosch B. Franzke C. Kozhuharov P.H. Mokler F. Nolden M. Steck T. Stöhlker T. Winkler H. Danared D.R. DeWitt H. Gao H. Lebius R. Schuch W. Spies W. Zong G.H. Dunn W.G. Graham J.A. Tanis J. Doerfert D. Savin Z. Stachura 《Hyperfine Interactions》1998,114(1-4):229-235
New recombination experiments with merged cold beams of electrons and atomic ions have been carried out at the storage ring
facilities TSR in Heidelberg, ESR in Darmstadt, and CRYRING in Stockholm. A brief overview is given on the recent activities
in which the Giessen group was engaged. Topics of this research were dielectronic recombination (DR) of astrophysically relevant
ions, recombination of highly charged ions with respect to cooling losses in storage rings, field effects on DR, search for
interference effects in photorecombination of ions, correlation effects in DR of low-Z ions, spectroscopy of high-Z ions by DR, and lifetimes of metastable states deduced from DR experiments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Z.K. Huang S.X. Wang W.Q. Wen X. Xu H.B. Wang S. Li L.J. Dou N. Khan S. Mahmood X.L. Zhu D.M. Zhao L.J. Mao X.M. Ma J. Li R.S. Mao J.C. Yang D.Y. Yin Y.J. Yuan C.Y. Chen L.F. Zhu X. Ma 《X射线光谱测定》2020,49(1):155-159
In order to extend the dielectronic recombination (DR) experiments from the main cooler storage ring CSRm with intermediate charge state ions to the experimental cooler storage ring CSRe with highly charged ions and even radioactive ions, a test electron-ion recombination experiment of B-like Ar13+ ions was performed with a section of the new electron beam energy detuning system, which will be installed at the CSRe. We present the measured and also the calculated DR spectra for the ∆n = 0 resonances from 0 to 3 eV. The experimental results agree very well with the previous DR experimental data from CRYRING, and the energy resolution reached 30 meV full width at half maximum. This test experiment demonstrates that the reliability and stability of the newly developed electron beam energy detuning system are satisfactory for the upcoming DR experiments at the CSRe. However, we found large discrepancies between the experimental result and the calculation in both resonance positions and the intensities of the recombination spectrum below 0.7 eV, which indicate that precise calculation of the DR spectrum of multielectron ions is still a challenge. 相似文献
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T.P. Donalson N.J. Peacock 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(7):599-604
Two sets of tables are presented which facilitate the rapid calculation of hydrogenic ion dielectronic recombination coefficients for ions of charge z?17 and for ions of charge z>17 相似文献
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We have calculated the angular distribution of photons emitted after dielectronic recombination of highly charged uranium
ions and obtained differential cross sections for resonant transfer and excitation in collisions of U90+ with C atoms using the impulse approximation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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冉贞贵 《原子与分子物理学报》2010,27(2)
采用相对论扭曲波方法,理论研究了高离化态类锂离子I50+、Ho64+、Bi80+的KLL双电子复合过程,得到了双电子激发态的共振能量和双电子复合截面,利用自电离和辐射跃迁速率,得到了对应谱线的总宽度,并与已有的理论和实验结果进行了对比,理论较好地解释了最近的实验结果。 相似文献
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采用相对论扭曲波方法,理论研究了高离化态类锂离子I~(50+)、Ho~(64+)、Bi~(80+)的KLL双电子复合过程,得到了双电子激发态的共振能量和双电子复合截面,利用自电离和辐射跃迁速率,得到了对应谱线的总宽度,并与已有的理论和实验结果进行了对比,理论较好地解释了最近的实验结果. 相似文献
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Fan-Chang Meng Chong-Yang Chen Yan-Sen Wang Ya-Ming Zou 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(11):2000-2008
Ab initio calculation of the total dielectronic recombination (DR) rate coefficient from the ground state 3s23p63d9(J=5/2) of Co-like tungsten is performed employing the relativistic distorted-wave approximation with configuration-interaction. The DR contributions mainly come from complex series 3d84ln′l′. The complex series 3p53d10n′l′, 3p53d94ln′l′ and 3d85ln′l′ also contribute significantly to the total DR rates at relatively high electron temperatures. The l′ and n′ dependences of the partial rate coefficient are investigated. The inclusion of decays into autoionizing levels followed by radiative cascades (DAC) enlarges the total DR rate coefficients by a factor of about 10%. The level-by-level extrapolation method is developed to include DAC effects. The total DR rate coefficients are fitted to an empirical formula. It is shown that at temperatures above 2.5 keV the Burgess-Merts (BM) semiempirical formula can provide DR results with an accuracy of about 15%, whereas at electron temperatures below 100 eV it underestimates the DR rate coefficients by up to a few orders of magnitude and its temperature dependence is completely inadequate. The comparison of the results for Ni-like and Co-like tungsten shows that these two sets of DR rate coefficients are very close in magnitude at relatively high electron temperatures. 相似文献
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E. Lindroth 《Hyperfine Interactions》1998,114(1-4):219-227
A procedure to calculate dielectronic recombination cross-sections based on relativistic many-body perturbation in an all
order formulation is presented. Complex rotation is employed in order to handle autoionizing states. The method is applied
to recombination of lithium-like neon and lithium-like argon and the results are compared with experiments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Suresh Chandra Ram Dularey 《Journal of Quantitative Spectroscopy & Radiative Transfer》1980,23(6):585-593
The intensities of lines emitted from the solar atmosphere and observed on earth are calculated by considering electron-impact excitation followed by radiative emission. In order to determine the contribution of dielectronic-recombination -excitation (DRE), the calculations have been repeated with the inclusion of DRE as a process for excitation, along with electron-impact excitation; the excited electron is assumed to deexcite through radiative emission. The DRE is found to contribute significantly and the contribution generally increases with a decrease in wavelength and an increase of ionic charge. 相似文献
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The calculations of the rate coefficients for dielectronic recombination (DR) along the NiI isoelectronic sequence in the ground state Au^{51+} through Cu-like 3d^9nln′f (n,n′=4,5,6) inner-shell excited configurations are performed using the spin-orbit-split array (SOSA) model. Resonant and nonresonant radiative stabilizing transitions and decays to autoionizing levels followed by radiative cascades are included. Collisional transitions following electron capture are neglected. The trend of the DR rate coefficients and the ratio of dielectronic satellite lines intensities with the change of the electron temperature are discussed. 相似文献
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We have observed dielectronic recombination of Ba+ and e(-) from a continuum of finite bandwidth in the presence of microwave fields of frequencies 8.08 and 12.05 GHz and amplitudes of up to 2 V/cm. There are sharp resonant enhancements when the microwave frequency matches the Deltan = 1, 2, and 3 resonances of the intermediate autoionizing Rydberg states, and we attribute the enhancements to resonant microwave Stark l mixing. The microwave field provides a simple and powerful way to enhance the recombination rate for incident electrons of a specific energy. 相似文献