相关论文: Effects of Flavor Dependence on Weak Decays of J/p…

We study the semileptonic decays of heavy mesons into light pseudoscalars by making use of dispersion relations. Constraints from heavy quark symmetry, chiral symmetry and perturbative QCD are implemented into a dispersive model for the…

For top quark decays into heavy quark mesons $\Upsilon$ and $\bar{B}_c^*$ , a complete calculation to the leading order both in QCD coupling constant $\alpha_s$ and in $v$, the typical velocity of the heavy quarks inside the mesons, is…

We report that, unlike most inclusive quarkonium-production processes, the production rate for p p -> J/psi+Upsilon+X dominantly depends on two not well-known long-distance nonrelativistic QCD matrix elements, <O_8^{J/psi}(^3S_1)> and…

The ${\Upsilon}(1S)$ ${\to}$ $B_{c}D_{s}^{\ast}$ weak decay is studied with the perturbative QCD approach firstly. It is found that (1) main contributions to branching ratio come from the longitudinal and parallel helicity amplitudes, (2)…

We have measured the time-dependent decay rate for the process $B \to J/\psi K^{*0}(892)$ in a sample of about 88 million $\Upsilon(4S) \to B\bar{B}$ decays collected with the BaBar detector at the PEP-II asymmetric-energy $B$ Factory at…

We investigate the effects of low-lying fermion eigenmodes on the QCD partition function in the $\epsilon$-regime. The fermion determinant is approximated by a truncated product of low-lying eigenvalues of the overlap-Dirac operator. With…

The mean transverse momenta of hadrons, <P_{\bot}>, produced in e^+ N deep inelastic scattering was studied as a function of the hadron energy fraction z and the Bjorken variable x. The statistical accuracy of the HERMES data permitted to…

To clarify the conflict between the theoretical predictions and experimental measurements of the inclusive J/psi production in Upsilon decay, We consider the alpha_s^6 order color-singlet contributions of processes Upsilon --> J/psi+gg and…

At the chiral restoration/deconfinement transition, most hadrons undergo a Mott transition from being bound states in the confined phase to resonances in the deconfined phase. We investigate the consequences of this qualitative change in…

This paper presents the two body weak nonleptonic decays of B mesons emitting pseudoscalar (P) and vector (V) mesons within the framework of the diagrammatic approach at flavor SU(3) symmetry level. Using the decay amplitudes, we are able…

I present a mini-review on the physics of heavy flavour baryons where I concentrate on the HQET description of their exclusive decay modes. In particular I discuss the structure of current-induced bottom baryon to charm baryon transitions,…

In the light of recent experimental data from the CLEO Collaboration we study, the decays of B mesons to a pair of pseudoscalar (P) mesons, and a vector (V) meson and a pseudoscalar meson, in the framework of factorization. In order to…

We study the effect of scalar leptoquark and $Z^\prime$ boson on the rare decays of $D$ mesons involving flavour changing transitions $c \to u l^+ l^- (l^\mp_i l^\pm_j)$. We constrain the new physics parameter space using the branching…

A relativistic constituent quark model is adopted to give an unified description of the leptonic and semileptonic decays of pseudoscalar mesons (\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form factors are found to…

We present an approach to study the decay modes of the $J/\psi$ into a vector meson and a tensor meson, taking into account the nature of the $f_2(1270)$, $f'_2(1525)$, $\bar{K}^{* 0}_2(1430)$ resonances as dynamically generated states from…

We present a comprehensive study of weak transition form factors and decay observables of the $B_s$ meson in transitions to pseudoscalar ($P$) and vector ($V$) mesons. The $B_s \to P(V)$ form factors are calculated using the self-consistent…

Besides the traditional strong and electromagnetic decay modes, ${\Upsilon}(nS)$ meson can also decay through the weak interactions within the standard model of elementary particle. With anticipation of copious ${\Upsilon}(nS)$ data samples…

Several measurements on $R_D, R_{D^*}$, and $R_{J/ \psi}$ by the BaBar, Belle, and LHCb experiments show significant deviations from their Standard Model (SM) predictions, which illustrate the fact that the concept of lepton flavor…

We review some rigourous consequences of flavour independence on the spectrum and properties of hadrons in potential models, with emphasis on hadrons with two heavy quarks, such as $(b\bar c)$ mesons and $(QQq)$ baryons.

In models with partially composite quarks, the couplings of quarks to the Z boson generically receive non-universal corrections that are not only constrained by electroweak precision tests but also lead to flavour-changing neutral currents…