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1.
对He,Ne,Ar,Kr和Xe原子体系中电子在动量空间的性质进行了系统的理论计算研究.采用自洽场HFR方法计算了坐标空间He,Ne,Kr和Xe原子体系单电子径向波函数,动量空间的单电子波函数由坐标空间原子体系单电子径向波函数通过运用傅立叶变换计算得到.在冲量近似条件下,进一步计算研究了这些原子的单电子动量密度分布和原子体系总的Compton轮廓.计算结果与已有的实验实验值和其他文献的理论计算结果比较表明,本文计算的结果是准确的.  相似文献   

2.
本文对类镓等电子序列GaI-XeXXIV离子4s^24p、4s^24p、4s^24d、4s4p^2、4p^3和4s^25s组态组级结果和组态相互作用了理论分析,找出沿等电子序列的变化规律。  相似文献   

3.
Measurement of the production cross section of the D+s D- s in e+e- annihilation at the Center-of-Mass Energy of s=4.03 GeV is reported in the paper. The cross section for the D+s D- s production has been measured using a data sample of 22.3 pb-1 collected with BES detector at BEPC e+e- collider. The D+ s measons are reconstructed in the π+,K*0 K+ and K0K+ decay modes. A total number of 94±13 singly tagged D+ s events is obtained from the three modes. This yelds the cross section value σ prod D+s D- s=(451±63±118)pb for D+ s D- s production. Based on the numbers of singly tagged D+ s events for each of the three decay modes,the decay branching fractions for D+ s→K *0 K+ and K0K+ have been determined to be (3.02±0.94±0.91)% and (3.28±1.22±0.94)%,respectively.  相似文献   

4.
The coupled equation method (CEM) has been applied to investigating the resonance structures for the ground state 1s22s 2S of the neutral lithium from the first threshold up to 64.5 eV. Resonance structures of atomic lithium due to single excitations of the 1s and 2s electrons are studied by infinite-order calculations in detail. The effect of spin-orbit splitting is also included for some of the low-lying 1s2snp(↑↓) resonance,and the influence of the interference between 1s2s 3Snp ↓ and 1s2s 1Snp ↑ states on the resonance structure has been confirmed theoretically. The results show that the presented technique can give the reasonable resonance structures very well in photoionization processes.  相似文献   

5.
采用单电子的双中心原子轨道强耦合方法,计算了H(1s)+H(2s)碰撞体系H(2s)失去电子过程的总截面,并与前人的实验结果进行了比较.研究表明,采用双中心原子轨道强耦合方法得到的H(1s)+H(2s)体系H(2s)失去电子过程的截面与实验比较符合.同时,还给出了H(1s)+H(2s)碰撞体系H(2s)电离过程、H(1s)俘获电子过程和H(2s)退激发到H(1s)过程的理论截面.  相似文献   

6.
We have observed K-shell and L-shell hollow beryllium atoms (2s(2)2p3s and 1s3s(2)3p) created by photoexcitation using synchrotron radiation. Resonance shapes were fitted to the Fano profile and the parameters were deduced. A Dirac-Fock calculation was performed to identify the configuration of the peaks and to predict other hollow atomic peaks. The results of the calculation were in good agreement with the experimental data. The comparison of the transition strength has revealed that the three-electron photoexcitation to the 1s3s(2)3p configuration is stronger than the two-electron photoexcitation to the 2s(2)2p3s configuration. This is attributed to the large overlap between the 2s orbital of the ground state (1s(2)2s(2)) with the orbital of the L-shell hollow state (1s3s(2)3p).  相似文献   

7.
The solitary wave and wave front are two important behaviors of nonlinear evolution equations. Geometrically, solitary wave and wave front are all plane curve. In this paper, they can be represented in terms of curvature c(s), which varies with arc length s. For solitary wave when s → ±∞, then its curvature c(s) approaches zero, and when s=0, the curvature c(s) reaches its maximum. For wave front, when s → ±∞, then its curvature c(s) approaches zero, and when s=0, the curvature c(s) is still zero, but c'(s) ≠ 0. That is, s=0 is a turning point. When c(s) is given, the variance at some point (x,y) in stream line with arc length s satisfies a 2-order linear variable-coefficient ordinary differential equation. From this equation, it can be determined qualitatively whether the given curvature is a solitary wave or wave front.  相似文献   

8.
用多组态Dirac-Fock方法,并系统考虑相对论效应、电子关联、弛豫效应等重要贡献,计算了NII离子2s22p3s 3P1—2s22p21D2和2s22p3s 1P1—2s22p23P0,1,2自旋禁戒跃迁概率和振子强度-通过比较计算证实:弛豫和关联效应对禁戒跃迁概率的影响非常大,考虑了这些效应后,计算结果有显著的改善-由跃迁概率和振子强度的计算值推断,2s22p3s 3P1—2s22p21D2的谱线强度应该比原有的理论预言值小- 关键词: 跃迁概率 多组态Dirac-Fock方法  相似文献   

9.
We have made the first observation of B(s)(0)→D(s)(*)+ D(s)(*)- decays using 23.6 fb(-1) of data recorded by the Belle experiment running on the Υ(5S) resonance. The branching fractions are measured to be B(B(s)(0)→D(s)+ D(s)-)=(1.03(-0.32-0.25)(+0.39+0.26))%, B(B(s)(0)→D(s)(*±) D(s)(?))=(2.75(-0.71)(+0.83)±0.69)%, and B(B(s)(0)→D(s)*+ D(s)*-)=(3.08(-1.04-0.86)(+1.22+0.85))%; the sum is B[B(s)(0)→D(s)(*)+ D(s)(*)-]=(6.85(-1.30-1.80)(+1.53+1.79))%. Assuming B(s)(0)→D(s)(*)+ D(s)(*)- saturates decays to CP-even final states, the branching fraction determines the ratio ΔΓ(s)/cosφ, where ΔΓ(s) is the difference in widths between the two B(s)-B(s) mass eigenstates, and φ is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain ΔΓ(s)/Γ(s)=0.147(-0.030)(+0.036)(stat)(-0.041)(+0.042)(syst), where Γ(s) is the mean decay width.  相似文献   

10.
超导电性二流体模型的适用性   总被引:1,自引:1,他引:0  
岳晓萍  邢怀民  赵合运 《低温与超导》2002,30(2):57-59,63
给出了由 2 B t=1α B t导出 2 B=1αB和由 js t=nse2m E导出 js=ensυs的证明 ,从而解决了 L ondon方程的理论缺陷 ,并讨论了 2 B t=1α B t与 2 B=1αB及 js t=nse2m E与 js=ensυs的适用性问题  相似文献   

11.
用全相对论多组态自洽场方法,计算了类硅离子的1s、2s、2p-、2p 、3s、3p-、3p、3d-、3d、4s、4p-、4p、4d-、4d、4f-、4f、5s、5p-、5p、 5d-、5d、5f-、5f、5g-、5g、6s、6p-、6p轨道的912个精细结构能级和辐射寿命以及各种跃迁参数.能级的计算值和实验值符合得很好.从计算结果中发现了一些亚稳态能级.  相似文献   

12.
基于去趋势波动分析方法确定极端事件阈值   总被引:7,自引:0,他引:7       下载免费PDF全文
杨萍  Hou Wei  封国林 《物理学报》2008,57(8):5333-5342
极端事件或者极值事件脱离了自身的正常演化状态,是系统演化的极端状态或系统受到外界扰动而导致的异常状态.去趋势波动分析法得到的指数是衡量系统在某一时间尺度内演化的长程相关性的参数,系统的长程相关性不受极端事件的影响或影响很小.基于这一思想,提出了利用去趋势波动分析法确定极端事件的阈值方法,并验证了该方法的有效性.使用该方法对北京极端高温事件、极端低温事件和极端降水事件进行了分析和讨论,确定北京1951—2004年极端高温、极端低温事件和极端降水事件的阈值.50余年来,北京极端高温和低温事件在20世纪70年代 关键词: 去趋势波动分析 极端事件 阈值  相似文献   

13.
The energy levels of the n = 5 complex configuration 5s2, 5s5p, 5s5d and 5p2 were computed for Cd I isoelectronic sequence ions from I VI to Sm XV by Hartree-Fock with relativistic corrections (HFR) method. By analyzing the variation of difference deltaE between energy levels calculated by HFR method and the experimental values with Z(c) along this isoelectronic sequence, the authors put forward a new fitting formula for generalized-least-square-fit (LSF) calculation. Using this formula and the FORTRAN programme designed by us, the energy levels of configurations mentioned above were calculated. The unknown energy levels of configuration 5s2 , 5s5p, 5s5d and 5p2 for ions from Nd XIII-Sm XV were predicted by extrapolation (or interpolation). Also, the wavelengths and HFR probabilities of transition 5s2-5s5p, 5s5p-5p2 and 5s5p-5s5d were computed. The calculated energy levels and wavelength results are in good agreement with corresponding experimental data reported in the references.  相似文献   

14.
SUMMARY: The purpose of this study was to compare maximum prolongations of controlled-intensity /s/ vs. /z/ in young healthy male and female adults and to compare the s/z ratio in young men and women. Twenty young adult men and 20 young adult women were included in this study. Participants produced 10 trials of /s/ and 10 of /z/ with a controlled intensity of 60-dB sound-pressure level (SPL). Maximum prolongations and s/z ratio were determined by three different methods: based on the longest out of 10 trials, the longest of 3 trials, and an average of the first 3 trials. Results revealed that based on averaged group data, /s/ and /z/ seemed to be prolonged for similar durations. Men consistently prolonged both phonemes significantly longer than women. There were no significant differences in s/z ratio between men and women. However, when individual data were reviewed, it seemed that some subjects consistently prolonged /s/ for a longer duration than /z/, some subjects prolonged /z/ longer than /s/, and some subjects actually produced approximately equal durations of the two phonemes. It was further noted that /s/ durations were more favorably impacted by practice than /z/ durations.  相似文献   

15.
利用组态相互作用理论和参数外推法,计算了KrVI离子4s~24p—4s4p~2、4s~24p—4s~24d和4s4p~2—4p~3跃迁的能级、谱线波长和振子强度。与已有实验结果比较表明:波长的理论计算值与观测值在0.7A内很好符合,振子强度的理论计算值较大的跃迁均是实验中观测到的跃迁。  相似文献   

16.
The operators of b→sγ,b→sl+l-are usually regarded as being sufficient to describe b→sγγ,b→sl+l-γwith the statement that contributions from diagrams without an effective vertex b→sγ to processes b→sγγand b→sl+l-γ are negligible.In this work we present a comprehensive analysis of the transition b→sγγand find that 1)Effects due to off-shell quarks in vertex b→sγ on b→sγγ are large; 2)Contributions from diagrams without an effective vertex b→sγ to b→sγγare not negligible compared with others; 3)These effects cancel each other out exactly,so the operators of b→sγ can safely be used to describe b→sγγ.  相似文献   

17.
用全相对论多组态自洽场方法,计算了高离化类铥铋原子BiXV的1s、2s、2p-、2p、3s、3p-、3p、3d-、3d、4s、4p-、4p、4d-、4d、4f-、4f、5s、5p-、5p、5d-、5d、5f-、5f、5g-、5g、6s、6p-、6p、6d-、6d、6f-、6f、6g-、6g、7s、7p-、7p、7d-、7d、7f-、7f、7g-、7g、8s、8p-、8p、8d-、8d轨道的2249个精细结构能级和辐射寿命以及其他各种跃迁参数.能级和波长的计算值和实验值符合得好.另外还发现了一些辐射寿命较长的亚稳态能级.  相似文献   

18.
Expressions are derived for the nonrelativistic energy of the 1s2s2p configuration. In both the possible electron momentum binding systems (1s2s)2p and 1s(2s2p) values are determined for the parameters of the generalized hydrogenlike analytical radial orbitals for a lithium atom and a negative helium ion. The Li and He energy spectra in the 1s2s2p configuration are compared with the theoretical calculations of other authors and with experimental data.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 70–74, June, 1977.  相似文献   

19.
We study the constraints on supersymmetric contributions to b-->s transitions from the recent allowed range and measurement of B(s)-B(s) mixing obtained by the D0 and Collider Detector at Fermilab collaborations at the Tevatron. We compute the upper bounds on the relevant off-diagonal squark mass terms and compare them with the bounds coming from delta F= 1 decays. We find that the constraints on chirality-flipping mass insertions are unaffected. Conversely, the measurement of B(s)-B(s) mixing is effective in constraining chirality-conserving mass insertions, and it has striking effects in the case in which left- and right-handed insertions have similar size. Finally, we discuss the phase of the B(s)-B(s) mixing amplitude in the presence of supersymmetric contributions.  相似文献   

20.
Three transitions of laser induced collision energy transfer from Eu (6s6p)8P5/2 to Sr (5s10s)1S0, Eu(6s6p)8P7/2 to Sr(5s9d)1D2 and Eu(6s6p)8Ps/2 to Sr(5s9d)1D2 have been observed in experiments. The relation between the breadth of spectral lines and the energy structures were analyzed experimentally and theoretically by two dipole-dipole interactions.  相似文献   

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