Abstract:
The charged pions, despite having a vanishing baryon number, do possess in general a nontrivial baryonic structure. Such feature is similar to the neutron that, despite being a neutral particle, has a nontrivial charge structure with associated form factors. However, in contrast to the neutron, whose associated form factors have been extensively studied in electromagnetic processes, the present case of study represents a more challenging situation. This is related to the lack of currents coupling to the baryon number in the SM.
In this study, we associate the nontrivial baryonic structure to isospin-breaking corrections, in particular to the difference of up and down quark masses. After estimating its size in different models, we propose a procedure to extract this property from experimental data, finding a nice agreement with model estimates.
Our results represent a new fundamental property of the pion and offers a benchmark for lattice QCD calculations, as well as the possibility to decipher the flavor structure of the pion.
Important: This seminar is remote only due to the COVID-19 regulations