Charmed Meson Production in Deep Inelastice+A Scattering at Small-x

Based on the nuclear effects considered in the Glauber-Gribov approach, charmed meson production in high energy deep inelastic e+A scattering is investigated in the color dipole formalism. Using the Peterson fragmentation function and the KLR-AdS/CFT color dipole model, which reasonably well describes the HERA data for the inclusive structure functions at small Bjorken-x, we present the predictive results for the D-meson transverse spectra at EIC and LHeC energies. The theoretical results indicate that the $x$-independence phenomena at very small-x predicted by the KLR-AdS/CFT model are not seen in our calculation.     

B→a0(1450)ρ(ω) Decays in Perturbative QCD Approach

In the two-quark model supposition for the meson a₀(1450), which can be viewed as either the first excited state (scenario I) or the lowest lying state (scenario II), the branching ratios and the direct CP-violating asymmetries for decays B→ a₀(1450)ρ(ω) are studied by employing the perturbative QCD factorization approach. We find the following results: (a) For the decays B^- → a⁰₀(1450)ρ^- and \bar{B}⁰ → a⁺₀(1450)ρ^-, their branching ratios have large
difference between two scenarios. Although their branching ratios are larger than other considered decay modes, their direct CP-violatingasymmetries in both scenarios are small. (b) For the decays B^-→ a^-₀(1450)ρ⁰ and \bar{B}⁰→ a^-₀(1450)ρ⁺, a⁰₀(1450)ρ⁰, a⁰₀(1450)ω, their branching ratios are close to each other between two scenarios, respectively. (c) Comparing with the decays \bar{B}⁰ →π⁰ρ⁰,π⁰π⁰, the decay \bar{B}⁰→ a⁰₀(1450)ρ⁰ receives a
larger branching ratio in each scenario, which is sensitive to the variation of the Cabibbo-Kobayashi-Maskawa angleα.     

The Three-Pion Decays of the a1(1260)

We investigate the decay of a₁⁺ (1260)→π⁺π⁺π^- with the assumption that the a₁(1260) is dynamically generated from the coupled channel ρπ and KK^* interactions. In addition to the tree level diagrams that proceed via a₁⁺ (1260)→ρ⁰π⁺→π⁺π⁺π^-, we take into account also the final state interactions of ππ→ππ and KK→ππ. We calculate the invariant π⁺π^- mass distribution and also the total decay width of a₁⁺ (1260)→π⁺π⁺π^- as a function of the mass of a₁(1260). The calculated total decay width of a₁(1260) is significantly different from other model calculations and tied to the dynamical nature of the a₁(1260) resonance. The future experimental observations could test of model calculations and would provide vary valuable information on the relevance of the ρπ component in the a₁(1260) wave function.     

Meson decays in an extended Nambu—Jona-Lasinio model with heavy quark flavors

In a previous work,we proposed an extended Nambu-Jona-Lasinio(NJL)model including heavy quark flavors.In this work,we will calculate strong and radiative decays of vector mesons in this extended NJL model,including lightρ,ω,K*,(?)and heavy D~*,D_s~*,B~*,B_s~*.     

J/ψ衰变中f0(975)的实验研究

本文基于北京正负电子对撞机(BEPC)上北京谱仪(BES)所收集到的国家自然科学基金资助.7.8×10⁶J/ψ事例,系统研究了J/ψ→φπ⁺π^－和J/ψ→ωπ⁺π^－两个衰变道,给出了过程的分支比以及f₀的位置和宽度参数,并对J/ψ→φf₀,f₀→π⁺π^－过程的角分布进行了拟合,首次确定出该过程的螺旋度振幅比.     

A multi-charged particle model with local U(1)μ-τ to explain muon g–2, flavor physics,and possible collider signature

We consider a model with multi-charged particles, including vector-like fermions, and a charged scalar under a local \begin{document}$ U(1)_{\mu - \tau} $\end{document} symmetry. We search for an allowed parameter region explaining muon anomalous magnetic moment (muon \begin{document}$ g-2 $\end{document}) and \begin{document}$ b \to s \ell^+ \ell^- $\end{document} anomalies, satisfying constraints from the lepton flavor violations, Z boson decays, meson anti-meson mixing, and collider experiments. Via numerical analysis, we explore the typical size of the muon \begin{document}$ g-2 $\end{document} and Wilson coefficients to explain the \begin{document}$ b \to s \ell^+ \ell^- $\end{document} anomalies in our model when all other experimental constraints are satisfied. Subsequently, we discuss the collider physics of the multicharged vectorlike fermions, considering a number of benchmark points in the allowed parameter space.     

对23P2介子九重态中同位旋标量成员的质量分析

基于实验上已经确认的基态张量介子九重态的安排和现有的实验数据,利用从雷吉轨迹理论和质量混合矩阵推导出的介子质量关系,对张量介子第一径向激发态的安排做了分析预测.根据得到的结果,可以推测f₂（1810）和f₂（2010）可能作为张量介子第一径向激发态的候选者.同时给出了f₂（1810）和f₂（2010）作为张量介子第一径向激发态时的衰变信息.这些结论对激发态张量介子,特别是其中的同位旋标量态的安排将提供帮助.     

Lattice calculation of the κ meson

We study the κ meson in 2+1 flavor QCD with sufficiently light u/d quarks. Using numerical simulations, we measure the point-to-point κ correlators in the "Asqtad" improved staggered fermion formulation. We then analyze these correlators using rooted staggered chiral perturbation theory (rSχPT), with particular attention paid to bubble contribution. After chiral extrapolation, we obtain the physical κ mass with 828±97 MeV, which is within the recent experimental value of 800-900 MeV. These numerical simulations are carried out with MILC 2+1 flavor gauge configurations at a lattice spacing of a ≈ 0.12 fm.     

Study of the heavy molecular states in the quark model with meson exchange interaction

Some charmonium-like resonances such as X(3872) can be interpreted as possible D^(*)D^(*) molecular states. Within the quark model, we study the structure of such molecular states and the similar B^(*)D^(*) molecular states by taking into account the light meson exchange (π, η, ρ, ω and σ) between two light quarks from different mesons.     

Photoproduction of Vector Meson ø off Deuteron in QCD Inspired Model

Based on the quark-gluon contents of nucleon and strongly believing that the force mediators, Pomeron and its counterpart in the conventional approach of Regge theory, for high energy diffractive process would be the tensor glueball and Odderonrespectively, we discuss photo-production of vector meson ø off the deuteron at energy less than 3 GeV in the QCD inspired model in which the quark gluon degrees of freedom and glueball, Odderon exchange are taken into account. A calculation isperformed for γ+D → ø+D, and the theoretical predictions of the differential cross section dσ ^γD/dt, are presented and compared with available experimental data. Our QCD inspired model reproduces data quite well in the whole range of the experimental measurements up to |t|≌ 0.4~GeV. Our results can be used toextract γn →øn data, which cannot be measured in experiment.