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1.
Physics of Atomic Nuclei - The fine-structure energy levels and lifetimes are calculated for the lowest 218 levels of the 2s22p5, 2s2p6, 2s22p43s, 2s22p43p, 2s22p43d, 2s2p53s, 2s2p53p, 2s2p53d,...  相似文献   

2.
We report transverse momentum (p(T)≤15 GeV/c) spectra of π(±), K(±), p, p[over ˉ], K(S)(0), and ρ(0) at midrapidity in p+p and Au+Au collisions at √S(NN)=200 GeV. Perturbative QCD calculations are consistent with π(±) spectra in p+p collisions but do not reproduce K and p(p[over ˉ]) spectra. The observed decreasing antiparticle-to-particle ratios with increasing p(T) provide experimental evidence for varying quark and gluon jet contributions to high-p(T) hadron yields. The relative hadron abundances in Au+Au at p(T)?8 GeV/c are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.  相似文献   

3.
ON          下载免费PDF全文
Formulae for the nuclear pairing-rotational (p.r.) and pairing-vibrational (p.v.) spectra are obtained using the PNC (particle-number-conserving) method. The quentum numbers characterizing the p.r. band, the braching ratios and the selection rule for two-particle transfer reactions are given. It is shown that the pairing-rotational scheme holds even for those nuclei near closed-shell, provided that the major-shell is not crossed. The anharmonic p.v. spectrum is shown to be equivalent to two sets of p.r. bands. The physical meaning of the parameters occuring in the p.r. and p.v. spectra is discussed.  相似文献   

4.
It is shown that, for fixed mass of the system X, the charged particle multiplicity distribution in the reaction p+p→p+X is remarkably similar to the shape of the multiplicity distribution for the reaction p+p→ anything observed at an equivalent fixed center of mass energy.  相似文献   

5.
The cross sections for the reactions 208Pb(p, pn)207mPb, 208Pb(p, p2n)206mPb have been measured for 24, 28, 36, 44 and 52 MeV incident protons. The experimental results are shown to be consistent with the clean knockout mechanism for the (p, pn) reaction and with knockout of one neutron followed by evaporation of another for the (p, p2n) reaction. We deduce a theoretical formula for the cross section for these reactions.  相似文献   

6.
Total and differential cross sections for p?p, pp, π±p, K+-p and Ψp at high energies are analysed in an additive eikonal quark model. It is shown that the exceptionally small Ψp slope contradicts the Chou-Yang model at present energies but can be accounted for by a quark-quark potential with different ranges for different pairs of quarks. This leads to smaller rms radii for hadrons than those derived from e.m. formfactors, implying that the constituent quarks have formfactors. Predictions for hadron-neutron and strange and charmed hadron-nucleon scattering are derived.  相似文献   

7.
袁萍  刘欣生  张义军  颉录有  董晨钟 《物理学报》2002,51(11):2495-2502
用相对论多组态DiracFock方法,系统地计算了与闪电过程有关的NII离子2p2,2s2p3,2p3s,2p3p,2p3d组态能级之间的辐射跃迁概率,并由此推算出这些组态的35个能级的寿命.计算中考虑了相对论效应、电子关联、延迟效应等重要贡献.与已有的理论计算比较,目前计算的结果更接近最新实验值.据此,进一步给出了2p3d3F能级寿命新的理论预言值  相似文献   

8.
类磷离子精细结构能级和辐射寿命   总被引:1,自引:1,他引:0  
用全相对论多组态自洽场方法,计算了9个类磷离子的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2309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。同时,我们还发现了一些亚稳态能级。  相似文献   

9.
There are 281 subgroups of index 4 for the 17 types of 2-dimension space groups: p1:7, p2:31, pm:19, pg:7, cm:11, p2mm:67, p2mg:23, p2gg:11, c2mm:31, p4:11, p4mm:31, p4gm:11, p3:4, p3m1:4, p31m:4, p6:4, p6mm:5. Every subgroup has been identified by its conventional cell disposition with respect to the conventional cell of the starting group. These subgroups may be arranged in 96 automorphism classes and 184 conjugation classes according to their starting groups.  相似文献   

10.
R.G. Lovas 《Nuclear Physics A》1976,262(2):356-364
The conditions for the self-consistency of the Lane potential are investigated by fitting the (p, p), (p, n?) and (n, n) differential cross sections in pairs. It is concluded that the model is correct only for average potentials to the accuracy of average potentials. The Lane potential can only be found by fitting (p, p) and (p, n?) data, and its real and imaginary parts should not be allowed to vary independently.  相似文献   

11.
王宛珏  姜仁滨 《光学学报》1991,11(8):704-707
本文用相对论多组态Dirae—Fock广义平均模型(MCDF-EAL)计算了可能成为激光工作物质的类氮VXVII、CrXVIII、MnXIX和FeXX的2s~22p~3、2s2p~4、2p~5、2s~22p~23s、2~2s2p~23p组态的各44个精细结构能级和33个3s—3p组态跃迁波长。其中关于VXVII、CrXVIII、MnXIX离子3s、3P组态的计算值是本文首次预言的。  相似文献   

12.
In the Color Glass Condensate formalism, charged hadron p T spectra in p+p and p+Pb collisions are studied by considering an energy-dependent broadening of nucleon density distribution. Then, in the glasma flux tube picture, the n-particle multiplicity distributions at different pseudo-rapidity ranges are investigated. Both the theoretical results show good agreement with the recent experimental data from ALICE and CMS at LHC energies.The predictive results for p T or multiplicity distributions in p+p and p+Pb collisions at the Large Hadron Collider are also given in this paper.  相似文献   

13.
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   

14.
Excitation functions and ranges of recoil nuclei in the 209Bi(p, 3n)207Po, 209Bi(p, 4n) 206Po and 209Bi(p, p3n)206Bi reactions have been measured for incident energies from 18 MeV up to 52 MeV. It has been found that the recoil ranges in (p, p3n) reactions are rather shorter than those in (p, 4n), and that beyond Ep = 40 MeV the high energy tail of the excitation function for (p, p3n) is roughly flat, in contrast to the decreasing tail for (p, 4n). A theoretical analysis of the excitation functions and of the nuclear recoil ranges has been made. It has been found that in (p, p3n) reactions the direct process plays a very important part in the reaction mechanism. It is also found that the reaction mechanisms of (p, 3n) and (p, 4n) reactions should be interpreted by means of an admixture of the equilibrium compound process and the pre-equilibrium decay process at bombarding energies up to 40 MeV and 50 MeV, respectively, and that the direct process seems to appear at bombarding energies higher than these respective energies.  相似文献   

15.
A simple relation, involving only experimental quantities, for the effective polarizations in quasi-free (p, 2p) scattering on closed shell nuclei is tested for recent TRIUMF (p, 2p) experiments with 200 MeV polarized protons.  相似文献   

16.
We studied the 12C(p,2p+n) reaction at beam momenta of 5.9, 8.0, and 9.0 GeV/c. For quasielastic (p,2p) events p(f), the momentum of the knocked-out proton before the reaction, was compared (event by event) with p(n), the coincident neutron momentum. For |p(n)|>k(F)=0.220 GeV/c (the Fermi momentum) a strong back-to-back directional correlation between p(f) and p(n) was observed, indicative of short-range n-p correlations. From p(n) and p(f) we constructed the distributions of c.m. and relative motion in the longitudinal direction for correlated pairs. We also determined that 49+/-13% of events with |p(f)|>k(F) had directionally correlated neutrons with |p(n)|>k(F).  相似文献   

17.
We present muSR experiments in the S=3/2 kagomé bilayer compound Ba(2)Sn(2)ZnGa(10-7p)Cr(7p)O22 [BSZCGO(p)] and compare it to the isostructural SrCr(9p)Ga(12-9p)O19 [SCGO(p)], including for the latter new results for p > or =0.89. Quantum-dynamical low energy magnetic excitations are evidenced in this novel compound. We study the evolution of the muon relaxation rate with p, T, and field. A phenomenological model for the muon relaxation based on sporadic dynamics due to spin excitations in a singlet sea proposed by Uemura et al. is extended to all fields and T range. Its connection to the RVB picture is discussed, and we argue that such coherent states might mediate the interactions between "impurities" which induce the spin glass freezing.  相似文献   

18.
Recently, S. Aggarwal et al. [Chin. Phys. B 24(2015) 053201] reported energy levels, radiative rates, and lifetimes for the lowest 148 levels belonging to the 3s23 p, 3s3p2, 3s23 d, 3s3p3 d, 3p3, 3p23 d, 3s3d2, 3p3d2, and 3d3 configurations of Al-like tungsten. While their calculated energies for the levels and the radiative rates for transitions are correct, the reported results for lifetimes are completely wrong. According to our calculations, errors in their reported lifetimes are up to 14 orders of magnitude for over 90% of the levels. Here we report the correct lifetimes and explain the reasons for discrepancies.  相似文献   

19.
The measurement of jet fragmentation functions in p+p collisions at 200 GeV is of great interest because it provides a baseline to study jet quenching in heavy-ion collisions. It is expected that jet quenching in nuclear matter modifies the jet energy and multiplicity distributions, as well as the jet hadrochemical composition. Therefore, a systematic study of the fragmentation functions for charged hadrons and identified particles is a goal both in p+p and Au+Au collisions at RHIC. Studying fragmentation functions for identified particles is interesting in p+p by itself because it provides a test of NLO calculations at RHIC energies. We present a systematic comparison of jet energy spectra and fragment distributions using different jet-finding algorithms in p+p collisions in STAR. Fragmentation functions of charged and neutral strange particles are also reported for different jet energies.  相似文献   

20.
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   

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