Related papers: Spin-1 particles and perturbative QCD
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…
The electromagnetic current~$J^+$ for spin-1, is used here to extract the electromagnetic form-factors of a light-front constituent quark model. The charge ($G_0$), magnetic ($G_1$) and quadrupole $G_2$ form factors are calculated using…
Spin-1 particles, is a fundamental bound state for the two quarks, and play a crucial role in elucidating the electromagnetic properties within the realm of hadronic physics. Their intrinsic relativistic nature mandates a quantum field…
We analyze the matrix element of the electroweak current between $q \qb$ vector meson states in the framework of a covariant extension of the light-front formalism. The light-front matrix element of a one-body current is naturally…
The electromagnetic current of spin-1 composite particles does not transform properly under rotations if only the valence contribution is considered in the light-front model. In particular, the plus component of the current, evaluated only…
For the vector sector, i.e, mesons with spin-1, the electromagnetic form factors and anothers observables are calculated with the light-front approach. However, the light-front quantum field theory have some problems, for example, the…
The contribution of the light-front valence wave function to the electromagnetic current of spin-1 composite particles is not enough to warranty the proper transformation of the current under rotations. The naive derivation of the plus…
In this paper, we study the $\rho$-meson electromagnetic form factors (EMFFs) within the framework of light-front quark model (LFQM). The physical form factors $G_{C,M,Q}(Q^2)$ of $\rho$-meson as well as the charged square radius $\langle…
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…
The violation of the rotational symmetry constraint of the matrix elements of the plus component of the vector current, in the Drell-Yan frame, is studied using an analytical and covariant model of spin-1 composite particle. The…
We calculate the gravitational form factors (GFFs) and pressure, shear and energy distributions for a quark state dressed with a gluon at one loop in QCD. We use the light-front Hamiltonian approach. In the light-front gauge, we use a…
The exclusive process $e^+e^-\rightarrow\Lambda\bar{\Lambda}$, with $\Lambda \to p\pi^-$ and $\bar{\Lambda} \to \bar{p}\pi^+$, has been studied at $\sqrt{s} =$ 2.396 GeV for measurement of the $\Lambda$ electric and magnetic form factors,…
The total cross sections of the process $e^+ e^-\to \Lambda_c^+ \bar{\Lambda}_c^-$ close to the threshold are calculated within the vector meson dominance model. It is found that the theoretical results can describe the current experimental…
Building on our successful technique to isolate the otherwise-elusive $\Lambda$(1405) using correlation matrix techniques and multiple source and sink smearings, we present calculations of the quark sector contributions to the electric form…
The connection between the Feynman triangle diagram and the light-front formalism for spin-0 and spin-1 two-fermion systems is analyzed. It is shown that in the limit q+ = 0 the form factors for both spin-0 and spin-1 systems can be…
The relativistic point-form formalism that we proposed for the study of the electroweak structure of few-body bound states is applied to calculate the elastic form factors of spin-1 mesons, such as the rho meson, within constituent-quark…
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…
Among countless channels of hard exclusive reactions, the kaon electromagnetic form factors (EMFFs) are of special interest, which have been measured up to $Q^2 \sim 50\;{\rm GeV}^2$ in the timelike domain. The kaon EMFFs thereby serve an…
Light-front current matrix elements for elastic scattering from hadrons with spin~1 or greater must satisfy a nontrivial constraint associated with the requirement of rotational covariance for the current operator. Using a model $\rho$…
A constituent quark model is developed for an arbitrary light- cone direction \omega. Form factors are obtained from free one-body electromagnetic current matrix elements. They are found to be \omega- independent for spin-0 mesons, the…