11–15 May 2026
El Escorial
Europe/Madrid timezone

Unpolarized twist-two GPDs and the role of different IR regulators

14 May 2026, 16:40
20m
El Escorial

El Escorial

Casa E. San José, Av. Reyes Católicos, 12 - 28280 El Escorial - Madrid

Speaker

Ignacio Castelli (Temple University)

Description

We present a one-loop perturbative study of unpolarized twist-two generalized parton distributions (GPDs) of quarks for external on-shell gluon states. A finite quark mass m is kept throughout the calculation and serves as an infrared regulator, allowing us to study the collinear limit of the GPDs. We also analyze this limit using dimensional regularization to regulate infrared divergences, and we discuss the implications of our results for the box diagram in deeply-virtual Compton scattering. Furthermore, by taking the second Mellin moment of the GPDs, we extract the associated form factors of the energy-momentum tensor (EMT) in both QED and QCD, with a special focus on the trace of the EMT. Particular attention is also given to potential anomaly-related pole contributions. This analysis complements our previous work on polarized twist-two GPDs and the axial anomaly.

Author

Ignacio Castelli (Temple University)

Presentation materials