Nonperturbative relativistic approach to pion form factor: predictions for future JLab experiments

TL;DR

This paper presents a nonperturbative relativistic model for the pion form factor, predicting future experimental outcomes at JLab and aligning well with existing data and QCD expectations.

Contribution

It introduces a Poincare invariant approach to the pion as a quark-antiquark system, providing accurate predictions and asymptotic behavior consistent with QCD.

Findings

Predicted pion form factor F_pi(Q^2) matches previous JLab measurements.

Model's predictions are robust against wave function variations.

Results agree with experimental values for pion radius and decay constant.

Abstract

Some predictions concerning possible results of the future JLab experiments on the pion form factor F_pi(Q^2) are made. The calculations exploit the method proposed previously by the authors and based on the instant-form Poincare invariant approach to pion considered as a quark-antiquark system. Long ago, this model has predicted with surprising accuracy the values of F_pi(Q^2) measured later in JLab experiment. The results are almost independent from the form of wave function. The pion mean square radius <r^2_pi> and the decay constant f_pi also agree with experimental values. The model gives power-like asymptotic behavior of F_pi(Q^2) at high momentum transfer in agreement with QCD predictions.