Mario L. L. da Silva

X(1835) Decay in the Fock-Tani Formalism

In this work we have obtained an effective Hamiltonian to describe the strong decay of pseudoscalar glueball, where the microscopic interaction between the constituent gluons have been taking into account. The pseudoscalar glueball candidate we have considered here is the X(1835) resonance. In our calculation the X(1835) was a pure glueball.

Photon-Photon Interaction in Glueball Production

In the last years many exotic states have been identified in several colliders around the world. One of the exotic states provided in QCD is the glueball. Using a non-relativistic gluon bound-state model, we compute Γ(G → γγ), where G is a pseudoscalar, tensor, or scalar digluon. For the starting from the amplitudes we considers the process γγ → g∗g∗ at threshold, where the amplitudes are obtained in perturbative QCD at lowest order by deriving them from QED calculation and the g∗s are massive constituent gluons. In this calculation the unknown parameters of the model, such as the digluon wave function, are obtained using measured values of Γ(J/Ψ → Gγ). Our theorical results are compared with the present experimental limits for the various glueballs candidates.

Light Meson Decay with Gaussian Confinement in a JKJ Decay Model

A form to describe hadron strong decays is in terms of quark and gluon degrees of freedom in microscopic decay models. Initially we assume that strong decays are driven by the same inter-quark Hamiltonian which determines the spectrum, and that it incorporates gaussian confinement. An A → BC decay matrix element of the JKJ Hamiltonian involves a pair-production current matrix elements times a scattering matrix element. Diagrammatically this corresponds to an interaction between an initial line and produced pair. In this work we apply the model to the light meson sector and calculate the decay rate, comparing with the experimental values.

DSJMesons Decay in the C3P0Model

Having its origin in a successful mapping technique, the Fock‐Tani formalism, has produced a corrected 3 P 0 model ( C 3 P 0 model), which retains the basic aspects of the 3 P 0 predictions with the inclusion of bound‐state corrections. In high energy collisions many new mesons have been discovered in particular the enigmatic D S0 + (2317) and D S1 + (2460). The model is applied for D SJ mesons decay. The amplitude and its respective decay rates are evaluated.

D[sub SJ] Mesons Decay in the C[sup 3]P[sub 0] Model

Having its origin in a successful mapping technique, the Fock‐Tani formalism, has produced a corrected 3 P 0 model ( C 3 P 0 model), which retains the basic aspects of the 3 P 0 predictions with the inclusion of bound‐state corrections. In high energy collisions many new mesons have been discovered in particular the enigmatic D S0 + (2317) and D S1 + (2460). The model is applied for D SJ mesons decay. The amplitude and its respective decay rates are evaluated.

ENERGY SPECTRA OF GLUINONIUM

We investigate relativistic bound states for a hypothetical light scalar gluino pair (gluinonium), in the framework of the covariant Bethe-Salpeter equation (BSE). In this paper, we derive, from the covariant BSE for a fermion-anti-fermion system, using charge conjugation, the corresponding bound-state equation for a gluino pair and we then formulate, for a static harmonic kernel, the coupled differential equations for the corresponding static Bethe-Salpeter amplitude. The steps of our approach then include a numerical solution of the Bethe-Salpeter amplitude for a two-body interaction consisting of scalar, pseudo-scalar, and four-vector components and the determination of the energy spectrum for the ground and the radially excited states of massive gluinonium. We found the energy spectrum and radial distributions of fundamental and excited states of gluinonium. The comparison of the values obtained in the extreme relativistic case with the corresponding values predicted by a harmonic oscillator potential model shows that there is good agreement between the two formulations. The predictions of the binding energy of glunionium in the non-relativistic model are however systematically higher.

DSJ Mesons Decay in the C3P0 Model

Having its origin in a successful mapping technique, the Fock‐Tani formalism, has produced a corrected 3 P 0 model ( C 3 P 0 model), which retains the basic aspects of the 3 P 0 predictions with the inclusion of bound‐state corrections. In high energy collisions many new mesons have been discovered in particular the enigmatic D S0 + (2317) and D S1 + (2460). The model is applied for D SJ mesons decay. The amplitude and its respective decay rates are evaluated.

GAUSSIAN CONFINEMENT IN A JKJ DECAY MODEL

In microscopic decay models, one attempts to describe hadron strong decays in terms of quark and gluon degrees of freedom. We begin by assuming that strong decays are driven by the same interquark Hamiltonian which determines the spectrum, and that it incorporates gaussian confinement. An A → BC decay matrix element of the JKJ Hamiltonian involves a pair-production current matrix elements times a scatering matrix element. Diagrammatically this corresponds to an interaction between an initial line and produced pair.

f0(1710) DECAY IN THE FOCK–TANI FORMALISM

We investigate the two-meson decay modes for f0(1710). In this calculation, we consider this resonance as a glueball. The Fock–Tani formalism is introduced to calculate the decay width.

MESON DECAY IN THE FOCK–TANI FORMALISM

The Fock–Tani formalism is a first principle method to obtain effective interactions from microscopic Hamiltonians. Usually this formalism has been applied to scattering; here we introduce it to calculate partial decay widths for mesons.