Electromagnetic mass splittings of heavier hadrons in quantum chromodynamics

The electromagnetic mass splittings of heavier hadrons are estimated in the framework of gauge theory model where ligher quarks are taken to behave relativistically and the spatial wave functions are described by the spin-spin interaction affected relative distances between quarks. The predictions for (Ξ⁻-Ξ⁰), (Σ*⁰−Σ*⁺), (Ξ^*−-Ξ^*0), (D _c ⁺−D _c ⁰) and (D _c ^*+ −D _c ^*0 ) are in fair agreement with the experimental data available whereas those for (D _b ⁻ −D _b ⁰ ) and (D _b ^*− −D _b ^*0 ) are in qualitative agreement with other theoretical estimates.     

Electromagnetic mass differences oft-flavored hadrons in modified bag model

Mass difference oft-flavored hadrons is calculated using bag model modified for considering heavy quarks inside the bag. Both electric and magnetic contributions to mass differences are evaluated without the assumption of degenerate intermediate state. Mass differences between up and down quarks inside the bag is taken to be a constant in the absence of a dynamical calculations for the same.     

Masses and some electromagnetic properties of charm andb-quark hadrons in a bag model with a variable bag pressure

We investigate how a new bag phenomenology with a variable bag pressure as its main ingredient is successful in reproducing various properties of heavy hadrons. Our results for masses, magnetic moments and M1 radiative decay widths indicate that these properties arise in a natural and consistent manner from the theory and that no additionalad hoc assumption is required to explain them.     

Study of heavy-light hadrons within a flux tube model

A classic mass loaded flux tube model and the diquark picture are employed to explore both mesons and baryons. The spectrum of A<'+><,c> baryons and D<,s> mesons is systematically obtained. The spin-orbit interaction in Ds was simplified as and (L→·S→) coupling.The spin-orbit interaction in Ac was simplified as a (J1→·Jc→) coupling. The predicted masses are consistent with the latest experiments.     

Study of heavy-light hadrons within a flux tube model

A classic mass loaded flux tube model and the diquark picture are employed to explore both mesons and baryons. The spectrum of Λ_c⁺ baryons and D_s mesons is systematically obtained. The spin-orbit interaction in D_s was simplified as an L·S coupling. The spin-orbit interaction in Λ_c was simplified as a J_l·J_c coupling. The predicted masses are consistent with the latest experiments.     

Gluon condensation and the bag model of hadrons

Migdal's scheme for gluon condensation is applied to a model where gluons are dynamically confined by coloured Higgs fields and are also subjected to ac-number colour field due to external “semiclassical” quarks. We show that, no matter how strong the external field becomes, stabilization of the gluonic ground state is guaranteed by the formation of an inhomogeneous gluon condensate. The contribution to the total energy from the condensate is computed semiclassically using a variational approximation. A physical interpretation of the results obtained is given in terms of a renormalization of the MIT bag model input parameters in particular the zero point energy coefficientZ and the bag constantB.

     

Strong decays of newly observed heavy flavor hadrons

In this talk, we briefly review the experimental status of newly observed charmed hadrons during the past years. Then we introduce the theoretical progresses on these charmed hadrons, especially our studies on the strong decays of new charmed hadrous during the past one year.     

Pionic and radiative decays of vector mesons in the chiral bag model

It is shown that a mechanism, within the framework of the cloudy bag model, analogous to that fore ⁺ e ^?→2ψ in QED accounts qualitatively for the decays ?→2π, ω→πψ and ?→πψ with a bag radii 0.8–1.0 fm, and averaged momenta for decay particles. For the radiative decays, the process identical to that in the vector-dominance model gives about 60% of the total calculated width. It also explains small decay widths previously calculated, using the single quark transition process.     

Recoil corrections to magnetic moments of charmed baryons in themit bag model

Recoil corrections to magnetic moments of charmed baryons are studied in themit bag model. It is noticed that such corrections which improve the octet baryon magnetic moments have considerably significant contributions to charmed baryon’s moments also.     

Strong decays of newly observed heavy flavor hadrons

In this talk, we briefly review the experimental status of newly observed charmed hadrons during the past years. Then we introduce the theoretical progresses on these charmed hadrons, especially our studies on the strong decays of new charmed hadrons during the past one year.     

Study of the e+e- to hadrons via ISR at BABAR

Experimental data from the PEP-Ⅱ B-factory at 10.6 GeV center-of-mass (c.m.) energy, obtained via initial-state radiation (ISR) with the BABAR detector, are presented. The cross sections for many hadronic processes have been measured from the production threshold to 4-5 GeV of the e+e- c.m. Energy. The obtained data allow to study a number of intermediate states and determine the parameters of known resonances and their branching fractions. The exclusive cross section for some number of hadronic sub-processes are presented.     

Quark model predictions on the masses of heavier vector mesons

We use the quark model considerations of Federman, Rubinstein and Talmi and the relation (m _ψ/m _ϕ)≃(m _ϒ/m _ψ)≃(m _ϒ/m _ϒ) to compute the masses of beautiful and tasty vector mesons.     

Bose analogs of the MIT bag model of hadrons in coherent precession

It has recently been demonstrated that magnon condensation in the trap exhibits the phenomenon of self-localization [1]. When the number of magnons in the textural trap increases, they drastically modify the profile of the gap and highly increase its size. The trap gradually transforms from the initial harmonic one to the box with walls almost impenetrable for magnons. The resulting texture-free “cavity” filled with the magnon condensate wavefunction becomes the bosonic analog of the MIT bag, in which hadron is seen as a cavity surrounded by the QCD vacuum, in which the free quarks are confined in the ground or excited state. Here, we consider the bosonic analog of the MIT bag with quarks on the ground and excited levels.     

Recoil corrections to magnetic moments of octet baryons in the MIT bag model

The presence of certain recoil corrections in the determination of baryon magnetic moments is described and taken into account for the octet members. Inclusion of these recoil corrections makes the MIT bag model, even in its zeroth-order version, very appealing, if the sum of many other corrections is not important by comparison.     

The influence of c.m. motion and chiral symmetry on masses and electroweak parameters of hadrons in the bag model

A thorough numerical analysis of the two major improvements of the original MIT bag model is presented. It is shown that the c.m. motion correction alone gives a good fit to hadron masses (including the qq? pion). The chiral-pion-cloud correction taken at full strength spoils this good agreement. If the quark-pion coupling is lowered by about 40% a reasonable fit is obtained again, while the electroweak parameters are well reproduced by both fits.     

Radiative corrections to masses in the standard model with two scalar doublets

We calculate the one loop corrections to the vector boson masses and the ? parameter in a standard model with two scalar doublets and a complex scalar singlet, the so-called “superlight axion” model. We find that the deviations from the corrections of the Weinberg-Salam model are practically unobservable when the spectator higges are very heavy.