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arXiv · 2410.17804

The electromagnetic pion form factor and its phase

Pablo Sanchez-Puertas·Enrique Ruiz Arriola
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Abstract

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward manner above the inelastic region, allowing us to obtain the form factor's phase, as well as its real and imaginary parts. As applications, we extract the $P$-wave $\pi\pi$ phase shift, the octet form factor, derive bounds in the spacelike region, and offer insights into the onset of perturbative QCD.

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Pablo Sanchez-Puertas, Enrique Ruiz Arriola. 2024-10-23. The electromagnetic pion form factor and its phase. https://arxiv.org/abs/2410.17804

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