The electromagnetic pion form factor and its phase

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 $\ddot{I}€\ddot{I}€$ phase shift, the octet form factor, derive bounds in the spacelike region, and offer insights into the onset of perturbative QCD.

Submitted proceedings to the 10th International Conference on Quarks and Nuclear Physics (QNP2024)