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Related papers: Covariance of Light-Front Models: Pair Current

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We apply the light-front reduction of the Bethe-Salpeter equation to matrix elements of the electromagnetic current between bound states. Using a simple (1+1)-dimensional model to calculate form factors, we focus on two cases. In one case,…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. C. Tiburzi , G. A. Miller

The rho-meson eletromagnetic form factors are calculated, both in covariant and light-front framework with constituintes quarks. The effect of the breakdown rotational symmetry for the one-body current operador in the null-plane is…

Nuclear Theory · Physics 2008-11-26 J. P. B. C de Melo , T. Frederico

A recent approach for constructing an exact 3D reduction of the 4D matrix elements of the electromagnetic current for an interacting two-fermion system, is briefly reviewed. The properties of the obtained 3D current, like the fulfillment of…

High Energy Physics - Phenomenology · Physics 2010-02-11 T. Frederico , J. A. O. Marinho , E. Pace , G. Salmé

We investigate the transition form factors between nucleon and $\Delta$(1232) particles by using a covariant quark-spectator-diquark field theory model in (3+1) dimensions. Performing a light-front calculation in parallel with the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jianghao Yu , Teng Wang , Chueng-Ryong Ji , Bo-Qiang Ma

We study the electromagnetic form factors, decay constants and charge radii of the pion and kaon within the framework of light-front field theory formalism where we use an ansatz for the quark-meson interaction bound-state function which is…

High Energy Physics - Phenomenology · Physics 2015-08-26 George H. S. Yabusaki , Ishtiaq Ahmed , M. Ali Paracha , J. P. B. C. de Melo , Bruno El-Bennich

We study the transition form factors between pseudoscalar and vector mesons using a covariant fermion field theory model in $(3+1)$ dimensions. Performing the light-front calculation in the $q^+ =0$ frame in parallel with the manifestly…

High Energy Physics - Phenomenology · Physics 2009-11-10 Bernard L. G. Bakker , Ho-Meoyng Choi , Chueng-Ryong Ji

We pursue applications of the light-front reduction of current matrix elements in the Bethe-Salpeter formalism. The normalization of the reduced wave function is derived from the covariant framework and related to non-valence probabilities…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. C. Tiburzi , G. A. Miller

We examine the light-front zero-mode contribution to the good(+) current matrix elements between pseudoscalar and vector mesons. In particular, we discuss the transition form factor $f(q^2)$ which has been suspected to have the light-front…

High Energy Physics - Phenomenology · Physics 2011-07-19 Ho-Meoyng Choi , Cheung-Ryong Ji

The frame dependence of the pair-term contribution to the electromagnetic form factor of the pion is studied within the Light Front approach. A symmetric ansatz for the pion Bethe-Salpeter amplitude with a pseudo scalar coupling of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. B. C. de Melo , T. Frederico , E. Pace , G. Salme

The divergences appearing in the 3+1 dimensional fermion-loop calculations are often regulated by smearing the vertices in a covariant manner. Performing a parallel light-front calculation, we corroborate the similarity between the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Bernard L. G. Bakker , Ho-Meoyng Choi , Chueng-Ryong Ji

A light-front Hamiltonian reproducing the results of two-dimensional quantum electrodynamics in the Lorentz coordinates is constructed using the bosonization procedure and an analysis of the bosonic perturbation theory in all orders in the…

High Energy Physics - Theory · Physics 2007-05-23 S. A. Paston , E. V. Prokhvatilov , V. A. Franke

Current matrix elements and observables for electro- and photo-excitation of baryons from the nucleon are studied in a light-front framework. Relativistic effects are examined by comparison to a nonrelativistic model and can typically be of…

Nuclear Theory · Physics 2007-05-23 Simon Capstick , B. D. Keister

We present a procedure to derive a covariant electromagnetic current operator for a system made up by two scalars constituents. Using different wave functions we fitted their parameters to the experimental data of the pion form factor,…

Nuclear Theory · Physics 2007-05-23 Mario A. Acero , Maurizio De Sanctis , Carlos E. Sandoval

We investigate the electroweak form factors and semileptonic decay rates of pseudoscalar and vector mesons using the light-front constituent quark model. Our method of analytic continuation in the Drell-Yan-West (q^+=q^0+q^3=0) frame to…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ho-Meoyng Choi

We find that the zero mode($q^{+}=0$ mode of a continuum theory) contribution is crucial to obtain the correct values of the light-front current $J^{-}$ in the Drell-Yan($q^{+}=0$) frame. In the exactly solvable model of (1+1)-dimensional…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ho-Meoyng Choi , Chueng-Ryong Ji

We study the radiative transitions between vector and pseudoscalar quarkonia in the light-front Hamiltonian approach, and investigate the effects of using different current component and different reference frames. In practical calculations…

Nuclear Theory · Physics 2020-11-03 Meijian Li

We study the structure of the $\rho$-meson within a light-front model with constituent quark degrees of freedom. We calculate electroweak static observables: magnetic and quadrupole moments, decay constant and charge radius. The…

High Energy Physics - Phenomenology · Physics 2015-03-16 Clayton S. Mello , Anacé N. da Silva , J. P. B. C. de Melo , T. Frederico

The electromagnetic elastic form factors of pseudoscalar and vector mesons are analyzed for space-like momentum transfers in terms of relativistic quark models based on the Hamiltonian light-front formalism elaborated in different reference…

Nuclear Theory · Physics 2009-11-07 Silvano Simula

We investigate the light-front zero-mode contribution to the weak transition form factors between pseudoscalar and vector mesons using a covariant fermion field theory model in $(3+1)$ dimensions. In particular, we discuss the form factors…

High Energy Physics - Phenomenology · Physics 2011-04-20 Ho-Meoyng Choi , Chueng-Ryong Ji

We investigate the angular momentum decomposition with a quantum electrodynamics example to clarify the proton spin decomposition debates. We adopt the light-front formalism where the parton model is well defined. We prove that the sum of…

High Energy Physics - Phenomenology · Physics 2015-01-09 Tianbo Liu , Bo-Qiang Ma