相关论文: Structure of Mass Gap between Two Spin Multiplets
The SU(3) breaking effects due to light quark masses on heavy meson masses, decay constants ($F_{D}, F_{D_{s}}$) and the form factor for semileptonic $\overline{B}\rightarrow D^{(\ast)} l\bar{\nu}_{l}$ transitions are formulated in chiral…
The contributions to heavy meson mass differences by the strong hyperfine interaction, the light quark masses and the electromagnetic interaction are obtained from the empirical values of the $D$, $D^*$, $B$ and $B^*$ masses by means of a…
We first review the work of the Syracuse group, which uses an effective chiral Lagrangian approach, on meson-meson scattering. An illustration providing evidence for the existence of a strange scalar resonance of mass around 900 MeV is…
The recent observation at the Tevatron of $\Sigma_b^{\pm}$ ($uub$ and $ddb$) baryons within 2 MeV of the predicted $\Sigma_b - \Lambda_b$ splitting and of $\Xi_b^-$ $(dsb)$ baryons at the Tevatron within a few MeV of predictions has…
We discuss the recent experimental observation which suggested that the mass difference between the scalar and pseudoscalar heavy-light mesons is larger for the non-strange states than for the strange ones. After computing the chiral…
We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…
The spectrum and dominant strong decay properties of the doubly heavy baryons are revisited by using a chiral effective model with chiral partner structure. By regarding the doubly heavy baryons in the ground states and light angular…
A detailed study of orbital and radial excited states in D, Ds, B and B_s systems is performed. The chiral quark model provides the framework for the calculation of pseudoscalar meson (pi, K, ...) hadronic transitions among heavy-light…
Present experiments in pursuit of the mass difference in the Bs-Bs(bar) system have put a lower bound on this quantity of $\Delta M_s > 14.9 ps^{-1}$ (at 95% C.L.). The same experiments also yield a local minimum in the log-likelihood…
We study the mass, width and couplings of the lightest resonance multiplet with I(J^{PC})=1(1^{--}) quantum numbers. Effective field theories based on chiral symmetry are employed in order to describe the form factor associated with the…
The $SU(3)$ and hyperfine mass splittings of mesons containing a single heavy quark are computed to one-loop order in chiral perturbation theory with heavy quark spin symmetry. Electromagnetic contributions of order $\alpha_em$ are…
An effective lagrangian incorporating both chiral and heavy quark symmetries and describing the low momentum interactions of heavy mesons and light scalar and vector resonances is presented. Using some available data and assuming nearest…
The spectrum of orbitally excited $D_s$ mesons is computed in the continuum limit of quenched lattice QCD. The results are consistent with the interpretation that the narrow resonance in the $D_s \pi^0$ channel discovered by the BABAR…
In this work, the mass and pole residue of $ X(4685) $ state with spin-parity $J^P=1^+$ are computed by the QCD sum rule approaches up to operator dimension seven based on the diquark-antidiquark configuration. For its mass we get $…
We calculate electromagnetic mass difference of mesons using a method proposed by Duncan {\it et al}. The RG-improved gauge action and the non-compact Abelian gauge action are employed to generate configurations. Quark propagators in the…
This is a follow-up to our earlier work for the energies and the charge (vector) and matter (scalar) distributions for S-wave states in a heavy-light meson, where the heavy quark is static and the light quark has a mass about that of the…
Isospin splittings in baryons with two heavy quarks and a $u$ or $d$ quark are calculated using simple methods proposed previously by the authors. The results are $M(\Xi_{cc}^{++})-M(\Xi_{cc}^+) = 1.41 \pm 0.12^{+0.76}$ MeV, $M(\Xi_{bb}^0)…
The discovery of the $D^\ast_{s0}(2317)$ and $D_{s1}(2460)$ resonances in the charmed-strange meson spectra revealed that formerly successful constituent quark models lose predictability in the vicinity of two-meson thresholds. The…
We perform a coupled-channels calculation of the masses of light mesons with the quantum numbers $IJ^{P=-}$, $(I,J)=0,1$, by including $q\bar{q}$ and $(q\bar{q})^2$ components in a nonrelativistic chiral quark model. The coupling between…
The spin and parity of the charmed mesons $D_{s}^{*+}$, $D^{*0}$ and $D^{*+}$ are determined for the first time to be $J^P=1^{-}$ with significances greater than 10$\sigma$ over other hypotheses of $2^{+}$ and $3^{-}$, using an $e^+e^-$…