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981.
^The polarization effect on the spin symmetry for anti-Lambda spectrum in 16 O+Λ system has been studied in relativistic mean-field theory.The PK1 effective interaction is used for nucleon-meson couplings and G-parity symmetry with a reduction factor ξ = 0.3 is adopted for anti-Lambda-meson couplings.The energy differences between spin doublets in the anti-Lambda spectrum are around 0.10-0.73 MeV for p Λ state.The dominant components of the Dirac spinor for the anti-Lambda spin doublets are found to be near identical.It indicates that the spin symmetry is still well-conserved against the polarization effect from the valence antiLambda hyperon,which leads to a highly compressed cold nucleus with the central density up to 2 - 3 times of saturated density. 相似文献
982.
The proton-rich isotope 146Ho was produced via the fusion-evaporation reaction ^92Mo (^58Ni, 3p1n). The β-delayed proton decay of 146Ho was studied by proton-γ coincidence measurements using a He-jet tape transport system. The γ-transitions in ^145Tb following the proton emissions were observed, and the β-delayed proton branching ratios to the final states in the grand-daughter nucleus ^145Tb were determined. According to the relative branching ratios, the ground-state spin of 146Ho has been proposed and the possible configuration discussed. 相似文献
983.
We investigate the bipartite entanglement dynamics of the system composed by three qubits A, B, and C. There is no interaction between A and B, and that of C and B is Dzyaloshinskii-Moriya (DM) spin-orbit interaction. We find that the purity of qubits A and B and the initial state of the qubit C are the two effective parameters to control the entanglement dynamics of the bipartite subsystems. This study sheds some lights on the control of quantum entanglement, which would be helpful for quantum information processing. 相似文献
984.
H. E. Jackson 《中国物理 C》2010,34(9):1247-1253
Results are presented from the Hermes experiment which uses semi-inclusive deep inelastic lepton scattering to study the flavor structure of the nucleon.Data have been accumulated for pion and kaon double spin asymmetries,single-spin azimuthal asymmetries for meson electroproduction,deep virtual Compton scattering (DVCS),and meson multiplicities.These results provide information on the properties of the strange sea in the proton,constraints on transverse momentum dependent quark parton distributions,and demonstrate the promise of DVCS for isolating the total angular momentum carried by the quarks in the proton. 相似文献
985.
G. K. Mallot 《中国物理 C》2010,34(9):1269-1274
The Compass experiment at CERN is studying the nucleon spin structure with a 160 GeV polarized muon beam and polarized targets as well as hadron structure with 190 GeV pion,kaon and proton beams.The paper gives an overview of the results for the helicity and transverse spin structure of the nucleon.A first result from the spectroscopy experiments,the observation of a resonance with exotic J P C = 1-+ quantum numbers at 1660 MeV is also presented.The paper ends with an outlook to future measurements. 相似文献
986.
We argue that the heavy quark spin symmetry can lead to important consequences for heavy flavor hadronic molecules.It can be used to predict new heavy flavor hadronic molecules and hence provides a method to identify the nature of some newly observed exotic hadrons.For example,if the Y(4660) were an S-wave ψ f 0 (980) shallow bound state,then the mass,width and line shape of its spin partner are predicted. 相似文献
987.
We review some recent progress in our understanding of the lowest-lying spin-1/2 and spin-3/2 baryon magnetic moments (MMs) in terms of Chiral Perturbation Theory (ChPT).In particular,we show that at next-to-leading-order ChPT can describe the MMs of the octet baryons quite well.We also make predictions for the decuplet MMs at the same chiral order.Among them,the MMs of the Δ++ and Δ + are found to agree well with data within the experimental uncertainties. 相似文献
988.
In the frame of quantum mechanics, we consider an ensemble of spin-1/2 neutral particles passing through a Stern-Gerlach apparatus and explore how their motions depend on the initial phase difference between two internal spin states. Assuming the particles moving along y-axis, due to the initial phase difference between spin states, they not only split along the longitudinal direction (z-axis) but also separate along the lateral direction (x-axis). The dependence of the lateral displacement on the initial phase difference reminds one of the picture of a quantum interference. This generalized interference provides an alternative approach to measuring the initial phase difference. The experimental realization with ultracold atoms or Bose-Einstein condensates is also discussed. 相似文献
989.
We use the first-order approximate solutions to the nonlinear system of Klein-Gordon-Maxwell-Einstein equations describing the minimally coupled charged spin-less field to a spherically symmetric spacetime to analyze a becoming boson star. In the far future and long-range approximation, we derive an analytical time-dependent charge which allows us to point out several significant moments in the evolution of the boson nebula. 相似文献
990.
Spin-dependent transport properties of the zigzag graphene nano-ribbon (zGNR) based structure Al-zGNR-Al are investigated by ab initio technique where density functional calculation is carried out within the Keldysh non-equilibrium Green's function formalism. The energy band structure of the infinite zigzag ribbon is sensitive to the dangling bonds of carbon atoms on both edge sides. For the three-circle-width zigzag ribbon with one edge monohydrogenated and the other edge dihydrogenated (zGNR(H-H2)), strongly spin-polarized energy bands are found. A spin-down branch is obtained just below the Fermi level while a spin up band appears above it. For the structure Al-zGNR(H-H2)-Al, where three-circle-width and seven-circle-length (3 × 7) zGNR(H-H2) is coupled by two (100) aluminium electrodes, an obvious spin filter property is found as the bias voltage changes. When the length of the sandwiched zGNR(H-H2) ribbon increaes, the spin-up current is strongly restrained especially under higher bias voltage. 相似文献