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arXiv · 2506.15128

Ambiguities in the Partial-Wave Analysis of the Photoproduction of Pairs of Pseudoscalar Mesons

Abstract

Applying the technique of partial-wave analysis, there are cases where more than one set of underlying complex-valued amplitudes can describe the measured observables. These ambiguities can sometimes be resolved using additional information, but assumptions are often required. It is known that the partial-wave analysis of two-pseudoscalar meson systems produced in photoproduction with a linearly polarized photon beam is free from discrete ambiguities stemming from the Barrelet zeros when the nucleon spin is ignored. In this article, we show that continuous ambiguities are possible for certain wave sets, even though the discrete ambiguities do not appear. We also explore ways to resolve these ambiguities and determine the maximal amount of information that can be obtained from analyses that suffer from these continuous ambiguities.

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J. Guo, E. Barriga, K. Scheuer, A. Austregesilo, P. Eugenio, D. I. Glazier, B. Grube, W. Imoehl, C. A. Meyer, A. Ostrovidov, J. R. Stevens. 2025-06-18. Ambiguities in the Partial-Wave Analysis of the Photoproduction of Pairs of Pseudoscalar Mesons. https://doi.org/10.1103/kjcp-h8b9

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