Kinematic power corrections to deeply virtual Compton scattering to twist-six accuracy

Authors:
Open Access
Publisher website
Google Scholar
Abstract
We calculate ( − t / Q ) k and ( m / Q ) k power corrections with k ≤ 4 , where m is the target mass and t is the momentum transfer, to several key observables in deeply virtual Compton scattering (DVCS). We find that the power expansion is well convergent up to | t | / Q 2 ≲ 1 / 4 for most of the observables, but is naturally organized in terms of 1 / ( Q 2 + t ) rather than the nominal hard scale 1 / Q 2 . We also argue that target mass corrections remain under control and do not endanger quantum chromodynamics (QCD) factorization for coherent DVCS on nuclei. These results remove an important source of uncertainties due to the frame dependence and violation of electromagnetic Ward identities in the QCD predictions for the DVCS amplitudes in the leading-twist approximation.
All Related Versions
Funding Information
  • Deutsche Forschungsgemeinschaft (409651613)
  • Chinese University of Hong Kong, Shenzhen (UDF01003869)
  • Chinesisch-Deutsche Zentrum für Wissenschaftsförderung
  • National Natural Science Foundation of China (12070131001)

This publication has 41 references indexed in Scilit: