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Pion Form Factor and Quark Mass Evolution in a Light-Front Bethe-Salpeter Model

L. S. Kisslinger·Ho-Meoyng Choi·Chueng-Ryong Ji
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Abstract

We discuss the soft contribution to the elastic pion form factor with the mass evolution from current to constituent quark being taken into account using a light-front Bethe-Salpeter (LFBS) model, which is a light-front quark model (LFQM) with a running mass. It is shown that partial conservation of the axial-vector current (PCAC) is satisfied with a running quark mass. We examine the sensitivity of the pion form factor using two different functional forms of the quark propagator. The Ball-Chiu ansatz is used to maintain local gauge invariance of the quark-photon vertex. The extension of our model to the hard contribution is also discussed.

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L. S. Kisslinger, Ho-Meoyng Choi, Chueng-Ryong Ji. 2001-01-06. Pion Form Factor and Quark Mass Evolution in a Light-Front Bethe-Salpeter Model. https://doi.org/10.1103/physrevd.63.113005

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