Unraveling the internal structure of pseudo-scalar mesons: from form factors to generalized parton distributions (Seminario Melany Higuera)


We conducted an extensive investigation into the internal structure of pseudo-scalar mesons, employing an unified algebraic model based on the Schwinger-Dyson equations (SDEs). Our study involved the calculation of various non-perturbative objects, such as electromagnetic (EFFs) and transition form factors (TFFs), parton distribution functions (PDFs), generalized parton distributions (GPDs), and impact parameter space GPDs. To achieve this, we employed two different approaches: the overlap approximation in the light front formalism and the triangle diagram approximation (impulse approximation). The overlap approximation of the light front wave function straitly related to the distribution amplitudes of quarks, allowed us to construct the GPDs, providing a 3D image of mesons. From these GPDs, we derived PDFs, EFFs, and the impact parameter space GPD. Furthermore, the PDFs of mesons containing the light valence quarks were evolved from the hadronic scale of approximately 0.3 GeV to the experimentally relevant scale of 5.2 GeV. Concurrently, the triangle diagram approximation facilitated the construction of EFFs and TFFs (M -> gamma gamma(^*)) in a simplified manner. This approach enabled us to fit the model's parameters through a global analysis, leading to excellent agreement with experimental and phenomenological results. We also determined the charge radius and presented our results for pion, kaon, eta_c, and eta_b using the algebraic model and compared these findings with previous theoretical approaches, including SDEs and lattice. Through these endeavors, we gained a comprehensive understanding of the capabilities and limitations of the algebraic model concerning pseudoscalar mesons. Our research significantly contributes to advancing our knowledge of the internal structure of these mesons, providing valuable insights for future studies.

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