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51.
A.G. Kofman 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,17(2):153-165
The electromagnetically induced transparency (EIT) with a (near-)resonant chaotic (amplitude-phase fluctuating, Gaussian-Markovian)
coupling field is studied theoretically. The Fourier transform of the steady-state EIT spectrum, which determines a nonstationary
probe absorption, is also considered. This quantity equals the average diagonal element of the (reduced) evolution operator
of the coupled transition (the evolution function). The exact solution in the form of a continued fraction is obtained and
used to perform numerical calculations. Moreover, a number of approximate analytical results are obtained, which, together
with the results of previous publications, describe the EIT and the evolution function in all possible regimes. In particular,
in the constructive-interference case the EIT increases with the coupling-field bandwidth ν at sufficiently small ν. For a strong field, the maximum of the transparency as a function
of ν is less than that for a monochromatic field of the same average intensity. In contrast, for a weak field, there is a
range of ν values, where the field fluctuations do not affect the EIT. The latter result is shown to hold for a broad class of stochastic fields.
Received 31 December 2000 and Received in final form 14 May 2001 相似文献
52.
K.S. Kim Myung Ki Cheoun Yeungun Chung Hyung Joo Nam 《The European Physical Journal A - Hadrons and Nuclei》2001,11(2):147-154
New results for the double beta decay of 76
Ge are presented. They are extracted from data obtained with the HEIDELBERG-MOSCOW experiment, which operates five enriched
76
Ge detectors in an extreme low-level environment in the Gran Sasso underground laboratory. The two-neutrino-accompanied double
beta decay is evaluated for the first time for all five detectors with a statistical significance of 47.7 kg y resulting in
a half-life of T
1/2
2ν = [1.55±0.01(stat)+0.19
-0.15(syst)]×1021 y. The lower limit on the half-life of the 0νββ decay obtained with pulse shape analysis is T
1/2
0ν > 1.9×1025(3.1×1025) y with 90% C.L. (68% C.L.) (with 35.5 kg y). This results in an upper limit of the effective Majorana-neutrino mass of 0.35
eV (0.27 eV) using the matrix elements of A. Staudt et al.'s work (Europhys. Lett. 13, 31 (1990)). This is the most stringent limit at present from double beta decay. No evidence for a majoron-emitting decay
mode is observed.
Received: 22 August 2001 / Accepted: 18 October 2001 相似文献
53.
P. Knowles J. Deutsch J. Egger W. Fetscher F. Foroughi J. Govaerts M. Hadri K. Kirch S. Kistryn J. Lang X. Morelle O. Naviliat A. Ninane R. Prieels N. Severijns L. Simons J. Sromicki S. Vandormael P. Van Hove 《Hyperfine Interactions》1999,118(1-4):73-76
Unlike the majority of Michel parameters which are consistent with the Standard Model V-A interaction, the experimental value of ξ″(=0.65±0.36) [1] is poorly known. Our experiment will measure the longitudinal polarization,
P
L
, of positrons emitted from the decay of polarized muons. The value of P
L
, equal to unity in the Standard Model, will decrease for high energy positrons emitted antiparallel to the muon spin if the
combination of Michel parameters ξ″/ξξ′ − 1 deviates from the Standard Model value of zero.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
54.
强相互作用中近似成立的SU(3)对称性被用来分析美介子半轻子三体和四体衰变,获得了衰变宽度之间的一些SU(3)联系.这些联系可以为了解美介子半轻子衰变中产生的各种动力学效应的性质提供一些信息. 相似文献
55.
The fluorescence decay of the 4F3/2 transition in neodymium-doped silica optical fibers is analyzed with respect to neodymium concentration and temperature. New experimental data are compared with theoretical calculations based on (i) Grant's supposition [W.J.C. Grant, Phys. Rev. B 4 (1971) 648] and (ii) the Förster [T. Förster, Ann. Phys. (Paris) 2 (1948) 55] and Dexter [D.L. Dexter, J. Chem. Phys. 21 (1953) 836] model. Grant's predictions are in reasonable agreement with the data. The nonexponential decay predicted by Förster and Dexter is insufficient to explain the experimental data. 相似文献
56.
In this Letter we develop a general procedure leading from a Mourre-type estimation for a given self-adjoint operator H to a Hardy-type weighted inequality. We use this method in order to prove exponential decay for eigenvectors of a large class of perturbations of operators of convolution with bounded analytic functions. 相似文献
57.
58.
利用有效液滴模型计算了偶偶超重核的α衰变半衰期,计算过程中采用了保持碎片体积守恒的不对称形状描述以及有效惯性系数计算Gamow势垒穿透因子.首先在质子数Z为88—98的区域检验了有效液滴模型,发现计算结果与实验符合得比较好.随后将此模型推广到Z≥100的情况,虽然只用了两个模型参数,计算结果与实验数据符合,说明有效液滴模型是计算偶偶超重核素α衰变半衰期的一个成功模型. 相似文献
59.
In a recent XUV photoabsorption spectrum of Cs Ⅲ ions by Cummings and O'Sullivan [2001 J. Phys. B 34 199], rather large linewidths were found for the 4d^95s^25p^6 - 4d^105s^25p^5 transition which are quite in disagreement with corresponding quasi-relativistic multiconfiguration Hartree Fock (MCHF) calculation. In the present work, a detailed multiconfiguration Dirac-Fock study has been carried out to explore this discrepancy. Owing to the detailed consideration of electron correlation effects, some ‘forbidden' Auger decay channels, such as 4d^105s^25p^35d and 4d^105s^05p^6, would become ‘open'. As a result, remarkable improvement of the linewidths has been obtained in our calculation. Furthermore, the theoretical Auger spectrum of the 4d^ 95s^25p^6 core-excited states of Cs Ⅲ ions is Riven in the present work. 相似文献
60.
简要地介绍了175Hf核ε衰变的IXK/Iγ(343keV)比值的计算方法与实验测量的比较与分析,并在此基础上,计算得到了Pγ(343keV)=0.869±0.004,还给出了175Hf核ε衰变的辐射数据的计算与推荐 相似文献