TY  - EJOUR
AU  - Braun, Vladimir
AU  - Jiang, Hua-Yu
AU  - Manashov, Alexander
AU  - von Manteuffel, Andreas
TI  - The two-loop coefficient function for double deeply virtual Compton scattering
IS  - DESY-24-178
M1  - PUBDB-2024-06709
M1  - DESY-24-178
M1  - arXiv:2411.14985
PY  - 2024
AB  - Making use of conformal symmetry of large-n f QCD in d = 4 − 2ϵ dimensions atthe Wilson-Fischer fixed point, we calculate the two-loop coefficient function in the operatorproduct expansion of two electromagnetic currents in a general kinematics with two differentphoton virtualities. This result is necessary for the description of the double deeply virtualCompton scattering to the next-to-next-to-leading order accuracy, but is also interesting fora range of other two-photon processes. We present analytic expression for the coefficientfunction in momentum fraction space in the MS scheme and study its numerical impacton the Compton form factors for a simple model of the generalized parton distribution. Thecalculated corrections turn out to be large and are significant in the kinematics of the proposedexperiments.
LB  - PUB:(DE-HGF)25
DO  - DOI:10.3204/PUBDB-2024-06709
UR  - https://bib-pubdb1.desy.de/record/617343
ER  -