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排序方式: 共有1768条查询结果,搜索用时 171 毫秒
961.
A. Küçükönder Ö. Sögüt C. Dozen B. G. Durdu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(1):37-39
Total M-shell X-ray production cross sections (M XRF) of the some elements in the atomic number range
were measured at 5.96 keV incident photon energy using a Si(Li) detector. The results are compared with the experimental
and theoretical values in the literature. 相似文献
962.
Jancovici derived the exactr
2 term in the expansion of the screening potential of the one-component plasma (OCP) around r = 0, which led to much improved
analysis of the simulation data, but the correspondingly important term has never been calculated for electron-screened plasmas.
The Onsager molecule approach provides the strong-coupling-limit result for the OCP screening potentials, features the exact
Jancovici r2 term, and gives a comprehensive physical picture of the structure of strongly coupled plasmas. It is used here to derive
the Strong-coupling screening potentials of electron-screened plasmas represented by the Yukawa potentials and, in particular,
the corresponding Jancovicir
2 term.
On sabbatical leave from the Nuclear Research Center Negev, P.O. Box 9001, Beer-Sheva, 84190, Israel. 相似文献
963.
The effect of processing factors on the inhomogeneity and physicomechanical characteristics of spray-on polyurethane foams is studied. The dependences of the basic characteristics of foam plastics on the apparent density and cell-shape factor are determined. A method is offered for evaluating the effect of the technological surface skin on the tensile characteristics of foam plastics under normal and low temperatures. 相似文献
964.
A constituent quark model is developed for an arbitrary light-cone direction so that the light-front time is xLF+ = ω · x with a constant lightlike four-vector ω. Form factors are obtained from free one-body electromagnetic current matrix elements. They are found to be ω-independent for spin-0 mesons, nucleons and the Λ-hyperon, while there is an ω-dependence for spin-1 systems like the deuteron. 相似文献
965.
本文推出了平均值的包含因子与测量次数n的正确关系,计算了两组实验结果的置信水准,纠正了文[1]的两个错误,得出了评定实验结果的一般结论。 相似文献
966.
Various symmetry relations developed between neutrino-neutron and antineutrino-proton elastic scattering cross sections are
surveyed and an identity between scattering amplitudes and a symmetry between cross sections of these processes established
by consideringCPT andG conjugation invariance of current matrix elements. A symmetry is obtained giving rise to a theorem on the nature of contribution
of form factors to terms in the cross sections. 相似文献
967.
A general method of obtaining wavefunctions for empirical diatomic molecular potential functions has been given. Efficacy
of the method has been tested by computing Franck-Condon factors for some bands of a new system of SiO using Morse oscillator
model and these have been compared with the ones obtained using exact Morse wavefunctions. It is concluded that the method
is satisfactory at low quantum numbers. 相似文献
968.
Bojan Magajna 《Proceedings of the American Mathematical Society》2001,129(3):771-780
Each weak* compact C-convex set in a hyperfinite factor (in particular in ) is the weak* closure of the C-convex hull of its C-extreme points.
969.
Bo-Wen Xiao Xin Qian Bo-Qiang Ma 《The European Physical Journal A - Hadrons and Nuclei》2002,15(4):523-527
The electromagnetic form factor of the kaon meson is calculated in the light-cone formalism of the relativistic constituent
quark model. The calculated K+ form factor is consistent with almost all of the available experimental data at low-energy scale, while other properties
of the kaon could also be interrelated in this representation with reasonable parameters. Predictions of the form factors
for the charged and neutral kaons at a higher-energy scale are also given, and we find the non-zero K0 form factor at Q
2≠ 0 due to the mass difference between the strange and down quarks inside K0.
Received: 21 June 2002 / Accepted: 29 July 2002 / Published online: 3 December 2002
RID="a"
ID="a"e-mail: mabq@phy.pku.edu.cn
Communicated by A. Sch?fer 相似文献
970.
Explicit evaluation of the following parameters has been carried out in the extraU (1) superstring inspired model: (i) As Mz2 varies from 555 GeV to 620 GeV and (m
t) CDF = 175.6 ± 5.7 GeV (Table 1): (a) SNew varies from -0.100 ± 0.089 to -0.130 ± 0.090, (b) TNew varies from -0.098 ± 0.097 to -0.129 ± 0.098, (c) UNew varies from -0.229 ± 0.177 to -0.253 ± 0.206, (d) Τz varies from 2.487 ± 0.027 to 2.486 ± 0.027, (e) ALR varies from 0.0125 ± 0.0003 to 0.0126 ± 0.0003, (f) A
FB
b
remains constant at 0.0080 ± 0.0007. Almost identical values are obtained for (m
t)D0 = 169 GeV (see table 2). (ii) Triple gauge boson vertices (TGV) contributions: AsMz
2 varies from 555 GeV to 620 GeV and (m
t) CDF = 175.6 ±5.7 GeV. (a)√s = 500 GeV, asymptotic case:
varies from -0.301 to -0.179;
varies from -0.622 to -0.379;
varies from +0.0061 to 0.0056;
varies from -3.691 to -2.186.
varies from +0.270 to +0.118;
varies from +0.552 to 0.238;
varies from +0.0004 to +0.0002;
remains constant at -0.110. (b)√s = 700 GeV, asymptotic case:
varies from -0.297 to -0.176;
varies from -0.609 to -0.370;
varies from -0.0082 to -0.0078;
varies from -3.680 to -2.171.√s = 700 GeV, nonasymptotic case:
varies from -0.173 to -0.299;
varies from-0.343 to -0.591;
varies from -0.005 to -0.011;
remains constant at -0.110.
The pattern of form factors values for√s = 1000, 1200 GeV is almost identical to that of√s= 700 GeV. Further the values of the form factors for (m
t)D0 (=169 GeV) follow identical pattern as that of (m
t) CDF form factors values (see tables 5, 6, 9, 10).
We conclude that the values of all the form factors with the exception of these of
,
are comparable or larger than theS, T values and therefore the TGV contributions are important while deciding the use of extraU (1) model for doing physics beyond standard model. 相似文献