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

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The role of Poincar\'e covariant space-time translations is investigated in the case of a relativistic quantum mechanics approach to the pion charge form factor. It is shown that the related constraints are generally inconsistent with the…

Nuclear Theory · Physics 2015-05-18 Bertrand Desplanques , Yu Bing Dong

In a set of two papers, we propose to study an old-standing problem, namely the electromagnetic interaction for particles of arbitrary spin. Based on the assumption that light-cone helicity at tree level and $Q^2=0$ should be conserved…

High Energy Physics - Phenomenology · Physics 2009-01-28 Cédric Lorcé

The light-front approach is applied to calculate the electromagnetic current for quark-antiquark bound states for the pion. The pion electromagnetic form factor is obtnaide from the "+" and "-" components of the electromagnetic current in…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. P. B. C. de Melo

We extend the confined covariant constituent quark model that was previously developed by us for mesons to the baryon sector. In our numerical calculation we use the same values for the constituent quark masses and the infrared cutoff as…

High Energy Physics - Phenomenology · Physics 2013-05-30 Thomas Gutsche , Mikhail A. Ivanov , Jurgen G. Korner , Valery E. Lyubovitskij , Pietro Santorelli

The elastic and $\gamma \to \pi$ transition form factors of the pion along with its usual static observables are calculated within a light-front field approach to the constituent quark model. The focus of this exercise in a simple model is…

Nuclear Theory · Physics 2015-06-18 J. P. B. C. de Melo , B. El-Bennich , T. Frederico

Within the framework of the covariant formulation of Light-Front Dynamics, we develop a nonperturbative renormalization scheme in the fermion model supposing that the composite fermion is a superposition of the "bare" fermion and a…

High Energy Physics - Theory · Physics 2009-11-10 V. A. Karmanov , J. -F. Mathiot , A. V. Smirnov

We present the first systematic investigation of the Lorentz covariance of the charge form factor for a strongly coupled scalar theory in (3+1)-dimensions. Our results are based on the first non-perturbative solution of the scalar Yukawa…

High Energy Physics - Phenomenology · Physics 2025-07-22 Wenyu Zhang , Yang Li , James P. Vary

The transition form factor for electrodisintegration of a two-body bound system is calculated in the Bethe-Salpeter framework. For the initial (bound) and the final (scattering) states, we use our solutions of the Bethe-Salpeter equation in…

High Energy Physics - Phenomenology · Physics 2015-05-20 J. Carbonell , V. A. Karmanov

Light front dynamics is a promising approach for calculating the deuteron wave function and form factors at high momentum transfers. However, in light-front dynamics rotational invariance is not manifest, which results in a splitting in the…

Nuclear Theory · Physics 2007-05-23 Jason R. Cooke

In this paper, we test the self-consistencies of the standard and the covariant light-front quark model and study the zero-mode issue via the decay constants of pseudoscalar ($P$), vector ($V$) and axial-vector ($A$) mesons, as well as the…

High Energy Physics - Phenomenology · Physics 2019-01-02 Qin Chang , Xiao-Nan Li , Xin-Qiang Li , Fang Su , Ya-Dong Yang

We investigate exchange current contributions to elastic electron-deuteron scattering using exactly Poincar\'e invariant quantum mechanics with a null-plane kinematic symmetry. Our model exchange current is motivated by one-pion-exchange…

Nuclear Theory · Physics 2009-09-11 Y. Huang , W. N. Polyzou

Electromagnetic form factors of the nucleon from relativistic quark models are analyzed: results from null-plane projection of the Feynman triangle diagram are compared with a Bakamjian-Thomas model. The magnetic form factors of the models…

High Energy Physics - Phenomenology · Physics 2014-11-17 K. Bodoor , H. J. Weber , T. Frederico , M. Beyer

The wave function of a composite system is defined in relativity on a space-time surface. In the explicitly covariant light-front dynamics, reviewed in the present article, the wave functions are defined on the plane $\omega \cd x=0$, where…

Nuclear Theory · Physics 2011-07-19 J. Carbonell , B. Desplanques , V. A. Karmanov , J. -F. Mathiot

The kaon electromagnetic form factor is calculated within a light-front constituent quark model (LFCQM). The electromagnetic components of the current are extracted from the Feynman triangle diagram within the light-front approach. We also…

High Energy Physics - Phenomenology · Physics 2015-06-11 Edson O. da Silva , J. P. B. C. de Melo , Victo S. Filho , Bruno El-Bennich

The electromagnetic form factors of the $\rho$ meson are evaluated adopting a relativistic constituent quark model based on the light-front formalism, and using a meson wave function with the high-momentum tail generated by the…

High Energy Physics - Phenomenology · Physics 2016-09-01 F. Cardarelli , I. L. Grach , I. M. Narodetskii , G. Salme' , S. Simula

We discuss the light-front zero-mode issue in the light-front quark model (LFQM) prediction of a vector meson decay constant from the perspective of the vacuum fluctuation consistent with the chiral symmetry of QCD. We extend the exactly…

High Energy Physics - Phenomenology · Physics 2015-06-17 Ho-Meoyng Choi , Chueng-Ryong Ji

We present calculations of radiative transitions between vector and pseudoscalar quarkonia in the light-front Hamiltonian approach. The valence sector light-front wavefunctions of heavy quarkonia are obtained from the Basis Light-Front…

High Energy Physics - Phenomenology · Physics 2018-08-28 Meijian Li , Yang Li , Pieter Maris , James P. Vary

We study the electron-positron pair production process in strong background electric fields with spatio-temporal inhomogeneity in the time-dependent Basis Light-front Quantization approach. We calculate the observables such as the invariant…

High Energy Physics - Phenomenology · Physics 2022-01-06 Zhiyu Lei , Bolun Hu , Xingbo Zhao

The pion electromagnetic form factor is calculated at lower and higher momentum transfer in order to explore constituent quark models and the differences among those models. In particular, the light-front constituent quark model is utilized…

High Energy Physics - Phenomenology · Physics 2016-10-19 J. P. B. C. de Melo , Rômulo Moreira Moita , Kazuo Tsushima

The electromagnetic form factors of a composite vector particle within the light-front formulation of the Mandelstam formula is investigated. In order to extract the form factors from the matrix elements of the plus component of the current…

High Energy Physics - Phenomenology · Physics 2018-12-26 J. P. B. C. de Melo