2024/03/11 by E. Ruiz Arriola, Arriola, Enrique Ruiz, Pablo Sánchez-Puertas +1 · 5 citations
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Pulsars and Gravitational Waves Research #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2403.07121
openalex publication_date 2024/03/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03
We employ a dispersion relation that allows to recover the phase of the electromagnetic form factor of the pion from its absolute value above threshold. Compared to alternative approaches building on the phase, this approach builds on experimental input directly accessible at colliders. Employing the precise datasets from the e+e-→π+π- reaction, we obtain the phase of the electromagnetic form factor up to 2.5~GeV, well beyond standard dispersive approaches. In addition, we separate the isovector and isoscalar components, that allows to extract the P-wave ππ phase shift. We also provide relevant results, including the radius of the form factor and bounds in the spacelike region. Last, but not least, the study assess potential systematic uncertainties from the interpolation method and potential zeros of the form factor.