Four-loop QCD cusp anomalous dimension at small angle
Abstract
We calculate the small angle expansion of the four-loop QCD cusp anomalous dimension. As a byproduct of our calculation, we also obtain the four-loop anomalous dimension of the heavy-quark field in HQET. The validity of the calculational setup is cross-checked by the independent calculation of the four-loop QCD beta-function from heavy-quark-gluon vertex renormalization in HQET. We check the obtained results for the cusp anomalous dimension and heavy-quark field anomalous dimension against available analytical and numerical results. Finally, we find that the maximal transcendentality contribution to the QCD Bremsstrahlung function coincides, up to a factor 3/2, with the Bremsstrahlung function in N = 4 supersymmetric Yang-Mills theory, at least, through 4 loops.
Keywords
Cite
@article{arxiv.2208.09277,
title = {Four-loop QCD cusp anomalous dimension at small angle},
author = {Andrey G. Grozin and Roman N. Lee and Andrey F. Pikelner},
journal= {arXiv preprint arXiv:2208.09277},
year = {2022}
}
Comments
ancillary files with results