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arXiv · 1708.03170

$\rho$-Meson Form Factors in the Point Form

Elmar P. Biernat·Wolfgang Schweiger
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Abstract

We present a calculation of the electromagnetic form factors of the $\rho^+$ meson. Our formalism is based on the point-form of relativistic quantum mechanics. Electron-$\rho$-meson scattering is formulated as a coupled-channel problem for a Bakamjian-Thomas mass operator, such that the dynamics of the exchanged photon is taken explicitly into account. The $\rho$-meson current is extracted from on-shell matrix elements of the optical potential of the scattering process. As a consequence of the violation of cluster separability in the Bakamjian-Thomas framework, our current includes additional, unphysical contributions, which can be separated from the physical ones uniquely. Our results for the form factors are in good agreement with other approaches.

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Elmar P. Biernat, Wolfgang Schweiger. 2017-08-10. $\rho$-Meson Form Factors in the Point Form. https://arxiv.org/abs/1708.03170

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