Static and dynamic properties of heavy light mesons in infinite mass limit

We summarize the consequences of the infinite limit of heavy quark mass in the results of form factors, charge radii and decay constants of heavy light mesons within a QCD inspired quark model recently reported.     

Stable and unstable classical solutions in an effective gauge theory for low energy mesons

We study the stability of two related classical solutions in an effective gauge theory, which correctly describes the properties of π and ρ mesons at low energies. The first solution (sphaleron), which excites only the ρ field, with baryon numberB=0 and energyE≈1.5 GeV is unstable. The second (Skyrmion), which excites both the π and ρ fields, withB=1 andE≈1.0 GeV is perhaps stable locally. We show how to make this Skurmion absolutely stable without raising its energy too much, both of which properties are desirable for identification with the nucleon. We comment on the potential of heavy ion collision experiments to study configuration space. The Skyrmion solution may also have some relevance for the electroweak interactions (nowE≈10 TeV).     

Non-leptonic B decays into two light mesons in soft-collinear effective theory

We consider non-leptonic B decays into two light mesons at leading order in soft-collinear effective theory, and show that the decay amplitudes are factorized at next-to-leading order in _s. The operators for non-leptonic B decays in the full theory are first matched to the operators in SCET_I, which is the effective theory appropriate for with Λ0.5 GeV. We evolve the operators and the relevant time-ordered products in SCET_I to SCET_II, which is appropriate for . Using the gauge-invariant operators in SCET_II, we compute non-leptonic B decays in SCET, including the non-factorizable spectator contributions and spectator contributions to the heavy-to-light form factor. As an application, we present the decay amplitudes for in soft-collinear effective theory.     

Electromagnetic mass differences of the old and the charmed mesons

We predict for M_?⁺?M_?⁰ the values -3.4 ± 0.8 MeV using the ?-ω mixing and the quark model, respectively. The extracted parameters indicate the necessity of a relativistic treatment of the old mesons. The problem of extrapolating these parameters to the charmed mesons is discussed. Under conservative assumptions, we predict 1.7 ? M_D⁰ ? 2.2 MeV and .     

Excited state mass spectra,decay properties and Regge trajectories of charm and charm-strange mesons

The framework of a phenomenological quark-antiquark potential(Coulomb plus linear confinement)model with a Gaussian wave function is used for detailed study of masses of the ground, orbitally and radially excited states of heavy-light Qq,(Q=c,q=u/d,s) mesons. We incorporate a O(1/m) correction to the potential energy term and relativistic corrections to the kinetic energy term of the Hamiltonian. The spin-hyperfine, spin-orbit and tensor interactions incorporating the effect of mixing are employed to obtain the pseudoscalar, vector, radially and orbitally excited state meson masses. The Regge trajectories in the(J,M~2) and(nr,M~2) planes for heavy-light mesons are investigated with their corresponding parameters. Leptonic and radiative leptonic decay widths and corresponding branching ratios are computed. The mixing parameters are also estimated. Our predictions are in good agreement with experimental results as well as lattice and other theoretical models.     

Pseudoscalar mesons and their radial excitations from the effective chiral Lagrangian

The effective chiral Lagrangian is derived from QCD in the framework of the field correlator method. It contains the effects of both confinement and chiral symmetry breaking due to a special structure of the resulting quark mass operator. It is shown that this Lagrangian describes light pseudoscalar mesons, and Gell-Mann-Oakes-Renner relations for pions, eta and K mesons are reproduced. The spectrum of radial excitations of pions and K mesons is found and compared to experimentally known masses.     

Nuclear surface properties in relativistic effective field theory

We perform Hartree calculations of symmetric and asymmetric semi-infinite nuclear matter in the framework of relativistic models based on effective hadronic field theories as recently proposed in the literature. In addition to the conventional cubic and quartic scalar self-interactions, the extended models incorporate a quartic vector self-interaction, scalar-vector non-linearities and tensor couplings of the vector mesons. We investigate the implications of these terms on nuclear surface properties such as the surface energy coefficient, surface thickness, surface stiffness coefficient, neutron skin thickness and the spin-orbit force.     

An analysis of the mass formulae forS- andP-wave mesons

Mass regularities forS- andP-wave mesons and relations between their masses are discussed. A detailed analysis is given forS-wave mesons which extends the investigations onP-wave mesons reported earlier. Masses for theS- andP-states of all interesting -systems (including toponium states) are predicted. Partial understanding of the mass formulae is obtained within a general potential model approach. Scaling arguments are presented which support the empirical scaling behaviour found for the expectation values determining the spin-splittings in the potential picture.     

Light meson mass dependence of the positive-parity heavy-strange mesons

We calculate the masses of the resonances D_s0^*(2317)\ensuremath D_{s0}^{\ast}(2317) and D_s1(2460)\ensuremath D_{s1}(2460) as well as their bottom partners as bound states of a kaon and a D^(*)\ensuremath D^{(\ast)} - and B^(*)\ensuremath B^{(\ast)} -meson, respectively, in unitarized chiral perturbation theory at next-to-leading order. After fixing the parameters in the D_s0^*(2317)\ensuremath D_{s0}^{\ast}(2317) channel, the calculated mass for the D_s1(2460)\ensuremath D_{s1}(2460) is found in excellent agreement with experiment. The masses for the analogous states with a bottom quark are predicted to be M_B^*s0=(5696±40)\ensuremath M_{B^{\ast}_{s0}}=(5696\pm 40) MeV and M_Bs1=(5742±40)\ensuremath M_{B_{s1}}=(5742\pm 40) MeV in reasonable agreement with previous analyses. In particular, we predict M_Bs1-M_Bs0^*=46±1\ensuremath M_{B_{s1}}{-}M_{B_{s0}^{\ast}}=46\pm 1 MeV. We also explore the dependence of the states on the pion and kaon masses. We argue that the kaon mass dependence of a kaonic bound state should be almost linear with slope about unity. Such a dependence is specific to the assumed molecular nature of the states. We suggest to extract the kaon mass dependence of these states from lattice QCD calculations.     

Strong and electromagnetic mass splittings in heavy mesons

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^∗$D^{\ast }$, B   and B^∗$B^{\ast }$ masses by means of a mass formula based on the heavy quark mass expansion. The three different types of contributions are determined with significant accuracy to next to leading order in that expansion.     

Static and dynamic properties of pseudoscalar mesons

We report the results of form factors, charge radii and decay constants of both light and heavy flavoured pseudoscalar mesons in a QCD inspired quark model. We use the quantum mechanical perturbation theory and discuss its limitations in the present problem. Several predictions are also made for bottom and top flavours.     

Comment of PCAC and the electromagnetic mass splittings of charmed mesons

Strong PCAC and a generalization of Dashen's relation for the K⁺?K⁰ mass difference as well as non-relativistic considerations are used in order to obtain insight into the mechanism which causes the mass splitting among the charmed pseudoscalar mesons D⁺ and D⁰. We find a value of 7–8 MeV for M_D⁺?M_D⁰.     

Semileptonic decays of charmed mesons in the effective action of QCD

Within the framework of phenomenological Lagrangians we construct the effective action of QCD relevant for the study of semileptonic decays of charmed mesons. Hence we evaluate the form factors of at leading order in the 1/N _C expansion and, by demanding their QCD-ruled asymptotic behavior, we constrain the couplings of the Lagrangian. The features of the model-independent parameterization of form factors are provided, and their relevance for the analysis of experimental data are pointed out. Received: 28 October 2002 / Published online: 24 January 2003     

The exchange of effective mesons between nucleons in nuclei

A study is made of the nuclear matter G-matrix. A method is developed which allows the determination of a local G-operator. This method is applied to analyse the correlations of the G-matrix, i.e. G without the bare interaction V, in terms of meson-exchange-type interactions. For a strong potential (REID) these effective mesons have masses which exceed 800 MeV implying very short-ranged correlations. For a weaker potential these correlations are somewhat longer ranged. The dominant feature of these G-operator correlations is found to be a strong scalar isoscalar attractive interaction which provides the binding of the nuclear system. By comparing with exact results for Landau parameters and binding energies it is shown that the approximation made with this local operator is excellent. A weak density dependence of the correlations is found and the structure of the Landau parameter ? is discussed. Finally it is proposed that this G-operator is a suitable object to study finite nuclei.