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arXiv · 1206.4721

Pion and kaon elastic form factors in a refined light-front model

Edson O. da Silva·J. P. B. C. de Melo·Bruno El-Bennich·Victo S. Filho
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Abstract

Within the framework of light-front field theory, we reassess the electromagnetic form factors of the pion and kaon. Comparison with experiment is made for the full range of momentum transfer, q^2<0, including recent data. The light-front model's single regulator mass, m_R, of the \bar qq bound-state vertex function is initially adjusted to reproduce the weak decay constants, f_π and f_K, and both meson's charge radii, r_π and r_K. We study the behavior of these observables under variation of the quark masses and find an optimized parameter set, m_u=m_d, m_s and m_R, for which they are in sensibly better agreement with experiment than in a previous analysis; a feature also observed for the elastic form factors, in particular at small q^2. This model refinement is important in view of an extension to vector and heavy-light mesons.

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Edson O. da Silva, J. P. B. C. de Melo, Bruno El-Bennich, Victo S. Filho. 2013-01-28. Pion and kaon elastic form factors in a refined light-front model. https://doi.org/10.1103/physrevc.86.038202

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