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231.
232.
利用基于多组态Dirac-Fock方法的程序包GRASP92和RATIP以及最新发展的RERR06程序,详细计算了高离化态金离子(类镍Au51+、类铜Au50+和类锌Au49+)俘获一个自由电子到nl(n=4—8,l=0—3)壳层的辐射复合谱以及相应的辐射退激发谱.理论计算的辐射复合谱很好地重现了实验谱.研究结果表明:对类镍Au51+、类铜Au50+和类锌Au49+而言,将一个自由电子俘获到n=4壳层的概率最大;在辐射复合过程之后,处在n=4壳层的俘获电子的辐射退激发谱线最强,并且体现了整个辐射退激发谱的主要特征. 相似文献
233.
基于分形理论,采用蒙特卡罗方法对随机分布的烟尘团簇粒子结构进行了仿真模拟,利用离散偶极子近似(discrete dipole approximation, DDA)方法研究了随机分布的烟尘团簇粒子的辐射特性,分析讨论了分形维数、原始微粒粒径和数量以及复折射率对随机分布烟尘团簇粒子辐射特性的影响.研究表明,在给定分形维数的情况下,烟尘团簇粒子的辐射特性取决于原始微粒粒径、数量及复折射率;原始微粒较小的团簇粒子,当分形维数较小时,吸收截面变化不明显,但当分形维数大于2时,吸收截面骤然增大,然而,对于具有比较大的原始微粒粒径、数量及复折射率的烟尘团簇粒子,吸收截面随着分形维数的增大而单调递减;随着分形维数的增大,团簇粒子的散射截面、消光截面及单次散射反照率均单调递增;从整体上来讲,团簇粒子的辐射特性与等效球形粒子的辐射特性存在着比较大的差别,并且这种差别随着分形维数的增大而减小.该工作对研究气溶胶粒子的辐射及气候效应具有重要的科学价值.
关键词:
烟尘团簇粒子
辐射特性
离散偶极子近似方法 相似文献
234.
In this rapid communication we describe an exciting platform technology that promises to fundamentally address two underlying
constraints of modern assays and immunoassays, namely sensitivity and rapidity. By combining the use of Metal-enhanced Fluorescence
(MEF) with low power microwave heating (Mw), we can significantly increase the sensitivity of surface assays as well as >95%
kinetically complete the assay within a few seconds. This technology is subsequently likely to find significant importance
in certain clinical assays, such as in the clinical assessment of myoglobin, where both the assay rapidity and sensitivity
are paramount for the assessment and treatment of acute myocardial infarction. 相似文献
235.
V. V. Anashin V. M. Aulchenko E. M. Baldin A. K. Barladyan A. Yu. Barnyakovet al 《中国物理 C》2010,34(6):831-835
We present a study of the inclusive photon spectra from 5.9 million J/ψ decays collected with the KEDR detector at the VEPP-4M e+e collider. We measure the branching fraction of radiative decay J/ψ→ηcγ, ηc width and mass. Our preliminary results are: M(ηc) = 2979.4± 1.5 ± 1.9 MeV/c^2, Г(ηc) = 27.8±5.1 ±3.3 MeV, B(Jψ→ηcγ) = (2.34±0.15±0.40)%. 相似文献
236.
Helmut Vogel 《中国物理 C》2010,34(6):621-625
We report recent results on charmonium spectroscopy and decay from the CLEO-c experiment at the Cornell electrompositron storage ring accelerator, CESR. Most of the results are based on the analysis of 54 pb-1 of luminosity collected at the ψ(2S) resonance, corresponding to 27 M ψ(2S) decays. We concentrate on radiative decays of ψ(2S) and J/ψ, on two-body mesonic decay of XcJ, on hadronic decay of the he, and on higher multipoles in the two-photon cascade ψ(2S)→γχcJ, XcJ→γJ/ψ. 相似文献
237.
G. Montagna G. Balossini C. Bignamini C. M. Carloni Calame O. Nicrosini F. Piccinini 《中国物理 C》2010,34(6):883-888
The status and accuracy of the precision Monte Carlo generators used for luminosity measurements at flavour factories is reviewed. It is shown that, thanks to a considerable, long-term effort in tuned comparisons between the predictions of independent programs, as well as in the validation of the generators against the presently available calculations of the next-to-next-to-leading order QED corrections to Bhabha scattering, the theoretical accuracy reached by the most precise tools is of about one per mille. This error estimate is valid for realistic experimental cuts, appears to be quite robust and is already sufficient for very accurate luminosity measurements. However, recent progress and possible advances to further improve it are also discussed. 相似文献
238.
PHOTOS Monte Carlo is widely used for simulating QED effects in decay of intermediate particles and resonances. It can be easily connected to other main process generators. In this paper we consider decaying processes γ*→π^+π^-(γ) and K^±→π^+π^-e^±υ(γ) in the framework of Scalar QED. These two processes are interesting not only for the technical aspect of PHOTOS Monte Carlo, but also for precision measurement of αED(Mz), g--2, as well as ππ scattering lengths. 相似文献
239.
We discuss a possible interpretation of the open charm mesons D*s0 (2317),D s1 (2460) and the hidden charm mesons X(3872),Y(3940) and Y(4140) as hadron molecules.Using a phenomenological Lagrangian approach we review the strong and radiative decays of the D* s0 (2317) and D s1 (2460) states.The X(3872) is assumed to consist dominantly of molecular hadronic components with an additional small admixture of a charmonium configuration.Determing the radiative (γJ/ψ and γψ(2s)) and strong (J/ψ2π and J/ψ3π) decay modes we show that the present experimental observation is consistent with the molecular structure assumption of the X(3872).Finally,we give evidence for molecular interpretations of the Y(3940) and Y(4140) related to the observed strong decay modes J/ψ+ω or J/ψ+φ,respectively. 相似文献
240.
PHOTOS Monte Carlo is widely used for simulating QED effects in decay of intermediate particles and resonances.It can be easily connected to other main process generators.In this paper we consider decaying processes γ*→π+π-(γ)and K±→π+π-e±ν(γ)in the framework of Scalar QED.These two processes are interesting not only for the technical aspect of PHOTOS Monte Carlo,but also for precision measurement ofαQED(Mz),g-2,as well as ππ scattering lengths. 相似文献