# XIII International Workshop on Hadron Physics - XIII Hadron Physics

22-27 March 2015
Hotel do Bosque
Brazil/East timezone

## Electromagnetic form factor for the K meson with a symmetric light-front model

Not scheduled
3h 30m
Hotel do Bosque

#### Hotel do Bosque

Rodovia Mário Covas (Rio-Santos) BR - 101 Sul, Km 533, Angra dos Reis, RJ, Brazil
Poster Field theoretical approaches to QCD

### Speaker

Mr George Yabusaki (UNICSUL)

### Description

The study of the lightest pseudoscalar mesons plays an important role in order to understand the low energy QCD,being the lightest strongly bound quark-antiquark states as well as the Goldstone bosons associated with chiral symmetry breaking. Their static and dynamical properties have also been investigated theoretically and experimentally. With respect to the description of bound states on the light cone, a detailed review of hadronic wave functions in QCD models can be found. Additional important knowledge about the meson's internal structure can be inferred from their valence-quark parton distribution functions. The theoretical framework we adopt is the light-front field theory formalism, more specifically, we here ameliorate the light-front approach, where two classes of quark-antiquark bound-state models for the Bethe-Salpeter amplitude of the K meson must be distinguished: the nonsymmetric and the symmetric vertex model. The light-front component $J^+$ of the electromagnetic current has been successfully used to calculate elastic form factors. For the symmetric vertex model, the components of the current are conveniently obtained in the Drell-Yan frame, where that on the light-cone the bound state wavefunctions are defined on the hypersurface $x^0+x^3 = 0$ and are covariant under kinematical boosts due to the stability of Fock-state decomposition. In this work, we consider the symmetrical quark-antoquark bound-state vertex function with the intention to optimize and unify the parameter set which simultaneously reproduces the K meson decay constants, charge radii and their electromagnetic form factors, for the latter, our numerical results are compared with experimental data up to $10~GeV^2$ in order to explore the validity of the model at large $q^2$ transfer.

### Primary author

Mr George Yabusaki (UNICSUL)

### Co-authors

Dr Ali Paracha (National University of Science and Technology) Prof. Bruno El-Bennich (UNICSUL) Dr Ishtiaq Ahmed (Quaid-I-Azam University) Prof. Joao Pacheco Bicudo Cabral de Melo (UNICSUL)

### Presentation Materials

There are no materials yet.