8–14 Jan 2026
University of Granada, Carmen de la Victoria
Europe/Madrid timezone

Hadronic form factors in QCD and the incompleteness problem in the time-like region

9 Jan 2026, 10:00
30m
University of Granada, Carmen de la Victoria

University of Granada, Carmen de la Victoria

Speaker

Prof. Enrique Ruiz Arriola (Universidad de Granada, Spain)

Description

Hadronic form factors are around since Hofstadter proved the finite proton size in 1955 in electron scattering experiments, identified as matrix elements of the em current. Since then, the nucleon and other hadronic form factors have been measured or computed in lattice QCD using all sorts of currents: electromagnetic, axial or gravitational. In the time-like region analyticity, chiral perturbation theory and perturbative QCD play a key role and imply a set of normalization and superconvergent sum rules which are rigorous conditions. We show several instances where these conditions are flagrantly violated due to a lack of information in the region above the largest known resonances and the below the onset of pQCD. We popose to use radial Regge trajectories to fill the gap and examine the consequences.

Author

Prof. Enrique Ruiz Arriola (Universidad de Granada, Spain)

Co-authors

Pablo Sanchez Puertas (University of Granada) Prof. Wojciech Broniowski (The Henryk Niewodniczański Institute of Nuclear Physics (IFJ))

Presentation materials