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1.
利用全相对论多组态Dirac-Fock方法系统地计算了高离化类铍离子的磁四极M2 2s21S0—2s2p3P2 (Z=10—103)自旋禁戒跃迁的能级间隔、跃迁概率和振子强度,计算中考虑了重要核的有限体积效应,Breit修正和QED修正,所得结果和最近的实验数据以及理论值进行了比较,结果表明:高原子序数的高电荷离子(Z≥70)磁四极M2自旋禁戒跃迁几乎可以和中性原子的光学允许跃迁相比拟,不仅在天体等离子体中,在ICF和MCF高温激光等离子体中,磁四极自旋禁戒跃迁和其他自旋禁戒跃迁(磁偶极、电四极)一样不容忽视,在双电子复合、不透明度、自由程等理论计算中应该考虑其影响. 关键词: 磁四极M2 能级间隔 跃迁概率 振子强度  相似文献   

2.
The measurement of the Bi80+ 2s1/2−2p3/2 transition energy is discussed. The measurement resolved the hyperfine splitting of the (1s22s) F=4,5 ground configuration and allowed a determination of the Lamb shift contributions with a precision of about 9 × 10-4 providing the most accurate test of QED in a high-Z ion to date. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

3.
Since the combination D 21 = 8f HFS(2s)-f HFS(1s) of hyperfine intervals in hydrogen and light two-body hydrogen-like atomic systems weakly depends on the nuclear structure, comparison between theory and experiment can be sensitive to high order QED corrections. New theoretical and experimental results are presented. Calculations have been performed for the hydrogen and deuterium atoms and for the helium-3 ion. Experiments on the 2s hyperfine splitting (responsible for the dominant contribution to the error in D 21) have been conducted for hydrogen and deuterium. The theory and experiment are in good agreement, and their accuracy is comparable to that attained in verifying the QED theory of the hyperfine splitting in leptonic atoms (muonium and positronium).  相似文献   

4.
The transition energies, wavelengths and oscillator strengths for the 1s22s-1s2 np (n ? 9) transitions of Ni25+ ion are calculated. In calculation of the energies, we not only take account of the firstorder corrections from relativistic and mass-polarization effects, but also estimate the higher-order relativistic contribution and QED correction by introducing the effective nuclear charge. The results agree with experimental data available in literature satisfactorily. Grotrian diagram showing these transitions is given.  相似文献   

5.
《Physics letters. [Part B]》2002,524(3-4):259-264
QED theory of the hyperfine splitting of the 1s and 2s state in hydrogen isotopes and helium-3 ion is considered. We develop an accurate theory of a specific difference 8EHFS(2s)−EHFS(1s). We take into account higher-order QED and nuclear structure effects. In particular, we found the vacuum polarization contribution in order α()3EF and examined the recoil contribution in order ()3m/M and thus completed a calculation of the fourth order QED corrections. The higher-order nuclear structure contributions were also analysed. The theoretical predictions reported here are now of a higher accuracy than the experiment. The study of the difference provides the most accurate test (at a level of a part in 108) of the QED theory of ns HFS up to date. The theory agrees with most of the experimental data.  相似文献   

6.
Results of an experiment to measure the 2P3/2?2S1/2 energy difference δ1 in the muonic (μ?4H e)+ ion are presented; we found δ1exp = 1.5274 ± 0.0009 eV. Comparison with QED predictions shows that there is agreement between theory and experiment within 0.0087 eV; this limitation is mainly due to the uncertainty with which the r.m.s. charge radius of the 4He nucleus is known.  相似文献   

7.
A calculated exhaustive set of vibrational state energies in 12C2H2, 13C2H2 and 12C2D2 has been used to analyse the evolution of the integrated number of states with increasing vibrational energy N(E) up to 15000 cm?1, 12000cm?1 and 10000 cm?1 in each isotopomer, respectively. The regular contribution to N(E) was modelled analytically and numerical parameters were fitted. The other expected contribution to N(E), which is of oscillatory nature, was quantified and is discussed using energyand time-dependent theories. Related periods of oscillation and temporal recurrences are interpreted consistently in terms of the constant of the motion Nr = 5v2 + 3v2 + 5v3 + v4 + v5 and of an average vibrational quantum. More pragmatically, the vibrational dynamics appear to be dominated by the bending vibrations, i.e., by the slowest oscillators.  相似文献   

8.
The wavelengths of the 1snp 1 P 1−1s 2 1 S 0 transitions in He-like Mg XI, F VIII (n= 4–8) and Al XII (n=6,9) have been calculated in the framework of the 1/Z expansion method including relativistic effects and QED contributions. It is found that QED corrections to the ground-state ionization energy are significant at the present level of experimental accuracy. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

9.
Hyperfine induced $1s2s\ ^1$ S $_0 \rightarrow 1s^2\ ^1$ S0 M1 transition probabilities of He-like ions have been calculated from relativistic configuration interaction wavefunctions including the frequency independent Breit interaction and QED effects. Present results for 151Eu and 155Gd are in good agreement with previous calculations [L.N. Labzowsky et al., Phys. Rev. A 63, 054105 (2001)]. Electronic data are given in terms of a general scaling law in Z that, given isotopic nuclear spin and magnetic moment, allows hyperfine induced decay rates to be estimated for any isotope. The results should be helpful for future experimental investigations on QED and parity non-conservation effects.  相似文献   

10.
The Dalgarno interchange theorem is used, together with the U function approach, to evaluate the first order perturbation corrections to <r 1 -1+r 2 -1> and <r 1 + r 2> for the two-electron states 1s2p 1 P and 1s2p 3 P. The results for <r 1 + r 2> are extended by using a screening approximation, and are compared with the results of accurate variational calculations. The first order perturbation correction to spin-weighted expectation values of type <ΣV(rj )szj > is given for the three-electron states 1s 22p 2 P and 1s 22s 2 S. The case V(rj ) = r j -1 is treated in detail.  相似文献   

11.
The g-factor anomaly, a≡(g?2)/2, has been measured for μ+ in the new Muon Storage Ring at CERN. The result is a = (1 165 895 ± 27) × 10?9. This is (13 ± 29) × 10?9 below the theoretical value which includes sixth-order QED terms and a hadronic contribution of (73 ± 10) × 10?9.  相似文献   

12.
Non-relativistic energies of 1s22s and 1s2 np (n⩽9) states for Co24+ ion are calculated by using the full-core plus correlation method. Our results of 1s22s and 1s22p states agree well with the high-precision results of Yan et al. Based on calculating the first-order corrections to the energy from relativistic and mass-polarization effects, we estimate the higher-order relativistic contribution and QED correction to the energy under a hydrogenic approximation. The transition energies, wavelengths and oscillator strengths for the 1s22s−1s2 np (n⩽9) transitions of this ion are calculated. The results agree with the experimental data available in literature satisfactorily. By combining with quantum defect theory, our theoretical predictions on the energy and oscillator strength of this ion are extrapolated to the whole energy region including continuous states.  相似文献   

13.
万建杰  董晨钟 《中国物理 B》2009,18(9):3819-3827
The multi-configuration Dirac-Fock(MCDF) method is implemented to study doubly excited 2s2p 1,3P1 resonances of the helium atom and the interference between photoionization and photoexcitation autoionization processes.In order to reproduce the total photoionization sprectra,the excited energies from the ground 1s2 1S0 state to the doubly excited 2s2p 1,3P1 states and the relevant Auger decay rates and widths are calculated in detail.Furthermore,the interference profile determined by the so-called Fano parameters q and ρ2 is also reproduced.Good agreement is found between the present results and other available theoretical and experimental results.This indeed shows a promising way to investigate the Fano resonances in photoionization of atoms within the MCDF scheme,although there are some discrepancies in the present calculations of the 2s2p 3P1 state.  相似文献   

14.
We study the small-x behaviour of the polarized photon structure function F3gF_3^{\gamma}, measuring the gluon transversity distribution, in the leading logarithmic approximation of perturbative QCD. There are two contributions, both arising from two-gluon exchange. The leading contribution to small-x is related to the BFKL pomeron and behaves like x-1-w2x^{-1-\omega_2}, w2 = O(aS)\omega_2 ={\cal O}(\alpha_S). The other contribution includes in particular the ones summed by the DGLAP equation and behaves like x1-w0(+)x^{1-\omega_0^{(+)}}, w0(+) = O(?{aS})\omega_0^{(+)} = {\cal O}(\sqrt{\alpha_S}).  相似文献   

15.
使用全实加关联方法和里兹(Ritz)变分方法计算了类锂体系(Z=21—30)基态1s22s的非相对论能量和波函数;包括动能修正、电子-电子接触项、轨道-轨道相互作用项以及Darwin项的相对论修正和质量极化项由全实加关联波函数的一阶微扰给出,量子电动力学修正QED(quantum electronic dynamic)由有效核电荷方法和类氢公式计算;给出了中等核电荷的高电离类锂体系基态的电离能、相对论效应的项能(term energy),并将计算结果与实验数据进行了比较,表明FCPC 关键词: 类锂体系 全实加关联 电离能 项能  相似文献   

16.
I present a detailed SUSY QCD calculation of the decay rate of the lightest Higgs bosonH 2 0 into two gluons, where all quarks and scalar quarks are taken within the relevant loop diagrams. I include the mixing of all the scalar partners of the left and right handed quarks and show that their contribution is more than several tens of per cent compared to the quark contribution in the MSSM for some SUSY parameter space. Furthermore the MSSM fermionic contribution is enhanced by several factors for large tanβ and large Higgs masses. As a result, the two gluon decay rate ofH 2 0 is much larger than the two gluon decay rate of an equal mass standard model Higgs boson. I further compare the decay mode ofH 2 0gg to the similar decay modes ofH 2 0cc andH 2 0bb including one loop QCD corrections and show that in some casesΓ(H 2 0gg) is even higher thanΓ(H 2 0cc), although still much smaller thanΓ(H 2 0bb).  相似文献   

17.
杨富利  易有根 《物理学报》2008,57(3):1622-1625
采用全相对论量子力学GRASP2程序,广义平均能级EAL模型,在核的有限体积效应,Breit和QED效应的高阶扰动基础上,考虑到原子实的极化,系统地计算了高剥离类钾离子4s 2S1/2─3d 2D3/2电四极矩E2光谱跃迁的能级间隔,跃迁概率和振子强度,结果表明:考虑原子实极化效应后,计算的精细能级结构间隔与实验数据之间的系统误差基本消除,其跃迁概率和振子强度属首次报道. 关键词: 高剥离态 能级间隔 振子强度  相似文献   

18.
Temperature dependencies of the specific heat in a temperature range of 14–260?K are presented for the crystals (TEA)2MnCl4. Two anomalies typical for the first order phase transition at T 1?=?224?K and T 2?=?231?K with entropy jumps of 15?J?mol?1?K?1 and 12?J?mol?1?K?1 were observed. The temperature dependence of the lattice heat was approximated by a linear combination of Debye and Einstein functions. Basing on the results an effective wave number of phonons with an essential contribution to the lattice oscillation energy was determined. Since phase transition sequence observed in (TEA)2MnCl4 and (TEA)2CuCl4 is similar and similar is the chemical composition one can suppose that the low temperature phase transition observed in (TEA)2MnCl4 crystals is an isostructural transition.  相似文献   

19.
在多通道量子亏损理论框架下,利用相对论多通道理论,分别在冻结实近似和考虑偶极极化下计算钪原子的Jπ=(3/2)-,(5/2)-的三个收敛于 3d4s(1D2)的自电离里德伯系列的能级.对3d4s(1D2)np2D3/2和3d4s(1 关键词: 相对论多通道理论 多通道量子亏损理论 电子-电子关联 自电离里德伯系列  相似文献   

20.
From an analogy with non-relativistic degenerate QED plasma we make an estimate of the coupling strength of QGP hypothesized to be present in compact star interiors. At densities ranging from 3ρ 0–10ρ 0 (normal nuclear density ρ 0=0.16 fm−3), quark matter is found to be strongly to intermediately coupled. The equation of state for QED plasma obtained via Pade approximation, modified to QGP, yields stable stellar sequences with maximum mass ≳2M for B 1/4≲215 MeV.  相似文献   

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