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1.
刘云虎 《中国物理 B》2009,18(5):1828-1832
<正>This paper discusses the masses and possible members of 21S0 and 23S1 meson multiplets in the framework of meson-meson mixing and Regge phenomenology.For the 21S0 meson nonet,K*(1460) may be the observed state of the 21S0 isodoublet with a mass of 1400 MeV and the mass ofω(1420) is 1412 MeV.For the 23S1 meson nonet,K*(1410) seems too light to be the 23S1 ns member.The fact that the agreement between the present findings and those given by experiments and other different approaches is satisfactory implies that the assignments in this paper may be reasonable.  相似文献   

2.
Mixing between the 23S1 and 13D1 Ds is studied within the 3P0 model. If mixing between these two 1- states exists, Ds1*(2700)± and DsJ*(2860)± could be interpreted as the two orthogonal mixed states with mixing angle θ≈ -80° in the case of a special β for each meson. However, in the case of a universal β for all mesons, Ds1*(2700)± could be interpreted as the mixed state of 23S1 and 13D1 with mixing angle 12° < θ < 21° but DsJ*(2860)± seems difficult to interpret as the orthogonal partner of Ds1*(2700)±.  相似文献   

3.
Within the framework of a nonlinear chiral Lagrangian the mass spectra and the decay properties of 0^++ states below 2 GeV are studied. Assuming that f0(980), a0(980), K0(1430), and f0(1500) comprise an SU(3) nonet, we make a detailed prediction about the static properties of the 0^++ mesons. The substructure analysis of these states in terms of two- and four-quark components as well as a glueball component is carried out. We also consider the interaction Lagrangian and provide a preliminary study of the strong and radiative decays of the 0++ mesons. The scalar glueball masses and partial widths are also presented. In view of the fact that few data of 0++ mesons are clearly given in the present PDG (Particle Data Group) list and that the four-quark content of mesons is a hot issue both experimentally and theoretically, the predicted results of the paper may be helpful for upcoming experimental and theoretical studies of these mesons.  相似文献   

4.
Near-infrared luminescence is observed from bismuth-doped GeS2-Ga2Sa chalcogenide glasses excited by an 808 nm laser diode. The emission peak with a maximum at about 1260 nm is observed in 80GeS2-2OGa2 Sa:O.fBi glass and it shifts toward the long wavelength with the addition of Bi gradually. The full width of half maximum (FWHM) is about 200 nm. The broadband infrared luminescence of Bi-doped GeS2-Ga2Sa chalcogenide glasses may be predominantly originated from the low valence state of Bi, such as Bi+. Raman scattering is also conducted to claxify the structure of glasses. These Bi-doped GeS2 Ga2Sa chalcogenide glasses can be applied potentially in novel broadband optical fibre amplifiers and broadly tunable laser in optical communication system.  相似文献   

5.
In the framework of quantum defect theory, we study super-excited states of F2 molecules which can dissociate into F^+ (^3P2,1,0) and F^-(^1 So) ion-pair. Based on our calculation, we present a vibrational resolved assignment of the high precision photofragment yield spectra for F^- from the F2 ion-pair production.  相似文献   

6.
冯学超  魏科伟  张贵杰 《中国物理》2006,15(12):2906-2908
In the framework of Regge phenomenology and meson meson mixing, this paper estimates the mass of isoscalar state (ss^-) of the 1^3D1 meson nonet, and the results given by two different approaches are 1735.51 ± 59MeV and 1730.29 ±46.SMeV.  相似文献   

7.
冯学超  李德民 《物理学报》2005,54(9):4084-4086
利用雷吉轨迹理论和介子九重态质量混合公式两种方案,对3介子九重态中同位旋标量态(主要是ss—成分)的质量给出预言,两种方案分别给出1853MeV和1849±1.2MeV.两种方案自洽的结果,将为实验上寻找该态的候选者提供帮助. 关键词: 雷吉轨迹 介子混合 同位旋标量态  相似文献   

8.
Recently, Gamal et al. [Chin. Phys. Lett. 22 (2005) 1530] reported the results of electrical conductivity, Hall effect and thermoelectric measurements on p-type Tl2S5 single crystals. From the experimental data for the temperature dependence of differential thermoelectric power, Gamal et al. determined thevalues of 2.66×10-41kg and 2.50×10-41kg, respectively, for the effective masses of electrons and holes in p-type Tl2S5, which are about ten orders of magnitude smaller than the free electron mass (9.11×10-31kg). We argue that the anomalously small values obtained for the effective mass of chargecarriers in Tl2S5 have no physical significance.  相似文献   

9.
Ca3Y2 (BO3)4:Eu^3+ phosphor is synthesized by high temperature solid-state reaction method, and the Iuminescence characteristics are investigated. The emission spectrum exhibits two strong red emissions at 613 and 621 nm corresponding to the electric dipole ^5 Do- ^7F2 transition of Eu^3+ under 365 nm excitation, the reason is that Eu^3+ substituting for Y^3+ occupies the non-centrosymmetric position in the crystal structure of Ca3 Y2 (BO3)4. The excitation spectrum for 613 nm indicates that the phosphor can be effectively excited by ultraviolet (UV) (254 nm, 365nm and 400nm) and blue (470nm) light. The effect of Eu^3+ concentration on the emission intensity of Ca3 Y2 (BO3)4 :Eu^3+ phosphor is measured, the result shows that the emission intensities increase with increasing Eu^3+ concentration, then decrease. The CIE colour coordinates of Ca3Y2 (BO3)4:Eu^3+ phosphor is (0.639, 0.357) at 15mol% Eu^3+.  相似文献   

10.
By an amplitudes analysis of the KKπ system in the J/ψ radiative decay to the K+KπO and the K0SK±π+ final states, we find that there is one 0-+ resonance (M=1467±3MeV,Γ=89±6MeV) and two 1++ resonances (M=1435±3MeV,Γ=59±5MeV and M=1497±2MeV,Γ=44±7MeV), Which are consistent with the η(1440), the f1(1420), and the f1(1510).  相似文献   

11.
The deuteron ground state mixed with 3D1 state is caused by the tensor potential of one meson exchange between two quarks.The properties of the deuteron 3S1+3D1 ground state are calculated with the chiral quark-confinement soliton model.  相似文献   

12.
The ^8Li(p, d)^7 Li reaction plays an important role in the inhomogeneous Big Bang nucleosynthesis and in the seed-nuclide production phase for the r-process. For the first time, its angular distribution at backward angles was measured in inverse kinematics at Ec.m.=4.0 MeV by using an ^8Li secondary beam. The result of measurement includes the contributions of ^8Li(p, d0)^7Li and ^8Li(p, d1)^7Li^*. The ^8Li(p, d0)^7Li component is estimated to be 40%-58% in the mixture angular distribution by analysing the measured result.  相似文献   

13.
The novel vacuum ultraviolet (VUV) excited Na3 Y9O3 (BO3)8:Tb^3+ (NYOB:Tb^3+) green phosphor is prepared. Strong VUV photoluminescence and high quenching concentration of Tb^3+ (20 wt%) are observed in NYOB: Tb^3+ and the strong emission are correlated with the unique layer-type structure of NYOB. All the characteristic 4 f - 5d transitions of Tb^3+ and the host absorption band in VUV region are identified in the excitation spectrum. Based on the results, the energy levels scheme of Tb^3+ in NYOB:Tb^3+ is first established. This newly developed NYOB:Tb^3+ phosphor shows excellent optical properties when compared with the commercial Zn2SiO4:Mn^2+ and would be a potential VUV-excited green phosphor.  相似文献   

14.
Three-body exit channel in the reaction 12C+16O at 56MeV has been studied by using measurement of the coincidence between the two changed particles.The projected spectra of the coinsidence between the two α-particles shows that the channel α+24Mg is the main intermediate process of three-body exit channel α12+20Ne in the reaction 12C+16O at 56MeV.The analysis of theoretical calculation showed that the sum of sequential decay and statistical break-up fit the experimental spectra satisfactorily.  相似文献   

15.
We discuss about the nature of f0(400-1200) which we decompose into three parts, i.e., t-channel ρ meson and f2(1270) meson exchange plus an additional s-channel resonance f0(X). Below 1.2GeV of ππ invariant mass, t-channel ρ meson exchange can explain the I=2 ππ S-wave scattering very well. However, the f2(1270) meson exchange must be considered for the ππ invariant mass above 1.2GeV. With the t-channel ρ meson and f2(1270) meson exchange fixed by the isotensor ππ→ππ S-wave scattering, we re-fit the CERN-Mülich(CM) data on ππ scattering to get parameters for the f0(X). We find that it is necessary to introduce a broad 0++ resonance with a pole about 1.6-1.7GeV.  相似文献   

16.
The ferroelectric crystal Ba2TiSi2O8 with high second-order optical nonlinearity is precipitated in Sm^3+-doped BaO-TiO2-SiO2 glass by a focused 800hm, 250 kHz and 150fs femtosecond laser irradiation. No apparent blue and red emissions are observed at the beginning, while strong blue emission due to second harmonic generation and red emission due to the f-f transitions of Sm^3+ are observed near the focal point of the laser beam after irradiation for 25s. Micro-Raman spectra confirm that Ba2 TiSi2O8 crystalline dots and lines are formed after laser irradiation. The mechanism of the phenomenon is discussed.  相似文献   

17.
Polarized Raman spectra of ferroelectric relaxor 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (0.67PMN-0.33PT) single crystal are systematically investigated in a wide temperature range from -196 to 600℃ by micro-Raman scattering technique. The results clearly reveal that there are two structural phase transitions in such composite ferroelectric relaxor: the rhombohedral-tetragonal (R- T) phase transition and the tetragonal-cubic (T- C) phase transition. The former occurs at about TR-T =34℃, corresponding to the vanishing of the soft A1 mode at 106cm^-1 recorded in the parallel polarization. The latter appears at about TT-C = 144℃, which can be verified with the vanishing of mode at 780cm^-1 measured in the crossed polarization.  相似文献   

18.
Anisotropic flows (v1, v2, v3 and v4) of light fragments up to the mass number 4 as a function of rapidity are studied for 25 MeV/nucleon ^40Ca + ^40Ca at large impact parameters by a quantum molecular dynamics model. A phenomenological scaling behaviour of rapidity dependent flow parameters vn (n = 1, 2, 3 and 4) is found as a function of mass number plus a constant term, which may arise from the interplay of collective and random motions. In addition, v4/v2^2 keeps to be almost independent of rapidity and remains a rough constant of 1/2 for all light fragments.  相似文献   

19.
By using an Ar^+ ion laser, a tunable Rh 6G dye laser (linewidth 0.5cm^-1) pumped by the second harmonic of a YAG:Nd laser and a Coherent 899-21 dye laser as light sources and using a monochromator, a phase-locking amplifier and a computer as the data detecting system, we detect the optical properties of Eu^3+-doped Y2SiO5 crystal. Persistent ,spectral hole burning (PSHB) are observed in the Eu^3+ ions spectral lines (^5 Do-T Fo transition) in the crystal at the temperature of 16K. For 15mW dye laser burning the crystal for 0.1 s spectral holes with hole width about 80 MHz both at 579.62nm and at 579.82nm are detected and the holes can remain for a long time, more than 10h.  相似文献   

20.
We analyse the available information on the production and three-body decays of the D(1285) meson in an attempt to establish its relationship to the A1(JPC = 1++) which mounting evidence suggests has a mass and width of 1100 and 250 MeV, respectively. In particular, we demonstrate that the narrow width of the D(20 to 30 MeV) is by no means incompatible with a broad A1 and SU(3) symmetry. Taking due account of the possible existence of a KA meson at 1340 MeV, we predict the decay properties of the ninth member of the nonet (the D') and argue that the E(1420) is not a viable candidate for this state.  相似文献   

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