Document Type

Article

Publication Date

2025

DOI

10.1103/PhysRevD.111.014002

Publication Title

Physical Review D

Volume

111

Pages

014002 (1-32)

Abstract

Forward photoproduction of 𝜋⁺𝜋⁻ pairs with invariant mass of the order of 𝑚𝜌 ∼770  MeV is traditionally attributed to Pomeron exchange. Based on a detailed analysis of the CEBAF Large Acceptance Spectrometer photoproduction data collected at photon energies below 4 GeV, it is shown from a study of the angular moments that the dynamics of two-pion photoproduction for |𝑡|≳0.5  GeV² cannot be explained by Pomeron exchange alone. This motivates the development of a new theoretical model of two-pion photoproduction which incorporates both two-pion and pion-nucleon resonant contributions. After fitting free parameters, the model provides an excellent description of the low moments of the angular distribution measured at CLAS and enables an assessment of the relative contributions of particular production mechanisms and an interpretation of the various features of the data in terms of these mechanisms.

Rights

© 2025 The Authors.

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP³.

Original Publication Citation

Bibrzycki, Ł., Hammoud, N., Mathieu, V., Perry, R. J., Akridge, A., Fernández-Ramírez, C., Montaña, G., Pilloni, A., Rodas, A., Shastry, V., Smith, W. A., Winney, D., & Szczepaniak, A. P. (2025). Studying 𝜋⁺𝜋⁻ photoproduction beyond Pomeron exchange. Physical Review D, 111, 1-32, Article 014002. https://doi.org/10.1103/PhysRevD.111.014002

ORCID

0000-0003-2702-5286 (Rodas)

Download

Share

COinS