Argonne Physics Seminar: Shohini Bhattacharya, Brookhaven National Laboratory

Deeply Virtual Compton Scattering (DVCS), where virtual photons scatter off nucleons to produce real photons, is often referred to as the ​‘golden process’ for accessing Generalized Parton Distributions (GPDs). In this presentation, we delve into the calculation of perturbative corrections for DVCS within a unique kinematic domain, specifically where t»\Lambda^2_{\rm QCD}, t representing the change in nucleon momentum following scattering. Working within this unconventional domain necessitated a distinctive approach, particularly dealing with non-zero values of t. Our calculation unveiled a previously undisclosed connection between GPDs and the chiral, as well as trace, anomalies of QCD. Of particular interest is the emergence of anomalies as infrared singularities when t approaches zero. Subsequently, we validate factorization up to one- loop  order  by  systematically  incorporating  these  singularity- related anomalies into the GPDs. This development not only expands the horizons of GPD research to encompass quantum anomalies but also opens up novel avenues for exploring their implications in both high-energy exclusive processes and the domain of lattice QCD investigations.

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