119227930
Baryonia and near-threshold enhancements
The baryon-antibaryon spectrum consisting of strange, charm and bottom quarks is studied in the color flux-tube model with a multi-body confinement interaction. Numerical results indicate that many low-spin baryon-antibaryon states can form compact hexaquark states and are stable against the decay into a baryon and an antibaryon. The multi-body confinement interaction as a binding mechanism plays an important role in the formation of the states. They can be searched in the $e^+e^-$ annihilation and charmonium or bottomonium decay if they really exist. The newly reported states, X(1835), X(2370), Y(2175), Y(4360) and Y_b(10890), may be interpreted as $N\bar{N}$, $\Delta\bar{\Delta}$, $\Lambda\bar{\Lambda}$, $\Lambda_c\bar{\Lambda}_c$ and $\Lambda_b\bar{\Lambda}_b$ states, respectively.
122838355
DYNAMICAL STUDY OF HEAVY-BARYON SPECTROSCOPY
The spectroscopy of S-wave heavy-baryons containing one, two or three heavy quarks is investigated in a constituent quark model. We solve the Schrodinger equation for three particles exactly by means of a Gaussian expansion method. The calculated results of heavy-baryon spectra with a single heavy quark are consistent with the experimental data.
119236514
Scalar Glueball in Radiative J/psi Decay on the Lattice
The form factors in the radiative decay of J/psi to a scalar glueball are studied within quenched lattice QCD on anisotropic lattices. The continuum extrapolation is carried out by using two different lattice spacings. With the results of these form factors, the partial width of J/psi radiatively decaying into the pure gauge scalar glueball is predicted to be 0.35(8) keV, which corresponds to a branching ratio of 3.8(9) x 10(-3). By comparing with experiments, out results indicate that f(0)(1710) has a larger overlap with the pure gauge glueball than other related scalar mesons. DOI: 10.1103/PhysRevLett.110.021601
119232831
Prediction for the mass spectra of resonance mesons in the soft-wall AdS/QCD model with a modified 5D metric
A soft-wall anti-de Sitter/QCD model with a modified five-dimensional metric at the infrared region is constructed to obtain a nontrivial dilaton solution, which incorporates the chiral symmetry breaking and linear confinement. By taking the pion mass and decay constant as two input mass scales, the resulting predictions for the resonance states of pseudoscalar, scalar, vector, and axial-vector mesons agree remarkably with the experimentally confirmed resonance states. The effects of the quartic interaction term are investigated by taking an appropriate sign and magnitude for maintaining the stability of the bulk scalar potential. It is shown that such a simply modified soft-wall anti-de Sitter/QCD model can lead to a consistent prediction for the mass spectra of resonance states in the pseudoscalar, scalar, vector, and axial-vector mesons; the agreement with the experimental data is found to be better than 10% for the excited meson states. The resulting pion form factor also agrees well with the experimental data.
118727023
Predictive AdS/QCD Model for Mass Spectra of Mesons with Three Flavors
The predictive soft-wall AdS/QCD model with a modified 5D metric at the infrared region is constructed to obtain a nontrivial dilaton solution for three flavor quarks u, d and s. Such a model is shown to incorporate both the chiral symmetry breaking and linear confinement. After considering some high-order terms including the U(1)(L) x U(1)(R) chiral symmetry breaking term, we find that the resulting predictions for the SU(3) octet and singlet resonance states of pseudoscalar, scalar, vector and axial-vector mesons agree well with the experimentally confirmed resonance states. Contributions from the instanton effects given by the determinant term are also discussed. It is observed that the chiral symmetry breaking phenomena of SU(3)(L) x SU(3)(R) and U(1)(L) x U(1)(R) can be well described in this model, while the SU(3) flavor symmetry breaking effect due to quark mass difference in the source term is not enough to explain all of the current experimental data.
120860773
Semileptonic Bc decay within heavy quark spin symmetry
Abstract We calculate the semileptonic B c decay widths using heavy quark spin symmetry. The form factors are estimated from the wave function model of Isgur, Scora, Grinstein and Wise (ISGW). We also discuss the extraction of | V cs |/| V cb |, | V cs |/| V cd | and | V ub |/| V cs | from semileptonic B c decays. The theoretical uncertainties are minimized when using the ratios of B c differential decay rates to extract the ratios of CKM elements at zero recoil limit. The result is potentially important for extracting CKM elements from future measurements at LHC and SSC.
119017430
B ---> PV decays in QCD improved factorization approach
Motivated by recent CELO measurements and the progress of the theory of B decays, we investigate $B\to P V(P=\pi,K. V= K^{*},\rho,\omega)$ decay modes in the framework of QCD improved factorization. We find that all the measured branching ratios are well accommodated in the reasonable parameter space and predictions for the other decay modes are well below the experimental upper limits. We also have calculated CP asymmetries in these decay modes.