Speaker
Amlan Chakraborty
(The Institute Of Mathematical Sceinces)
Description
We present the computation of the four-loop QCD corrections to the massless quark form factor with an external axial-vector current. Particular attention is devoted to the singlet contributions, which require a careful and consistent treatment of the axial current and γ₅ within dimensional regularisation. We analyze the ultraviolet renormalization and elucidate the infrared pole structure of the form factor in this order. Our results provide virtual ingredients for future precision studies of Z boson production at N^4LO QCD.
