Two-photon processes in conformal QCD: Resummation of the descendants of leading-twist operators
| Autor: | Braun, V. M., Ji, Yao, Manashov, Alexander |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
field theory: conformal
current: electromagnetic generalized parton distribution High Energy Physics::Phenomenology twist: 4 operator product expansion conformal symmetry deeply virtual Compton scattering resummation photon photon: annihilation quantum chromodynamics tree approximation DVCS operator: twist perturbation theory two-photon |
| DOI: | 10.3204/pubdb-2020-04705 |
| Popis: | Using some techniques of conformal field theories, we find a closed expression for the contribution of leading twist operators and their descendants, obtained by adding total derivatives, to the operator product expansion (OPE) of two electromagnetic currents in QCD. Our expression resums contributions of all twists and to all orders in perturbation theory up to corrections proportional to the QCD $\beta$-function. At tree level and to twist-four accuracy, our result agrees with the expression derived earlier by a different method. The results are directly applicable to deeply-virtual Compton scattering and, e.g., $\gamma\gamma^\ast$ annihilation in two mesons. As a byproduct, we derive a simple representation for the OPE of two scalar currents that is convenient for applications. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|