The three-loop singlet contribution to the massless axial-vector quark form factor
نویسندگان
چکیده
We compute the three-loop corrections to quark axial vector form factor in massless QCD, focusing on pure-singlet contributions where current couples a closed loop. Employing Larin prescription for γ5, we discuss UV renormalization of factor. The infrared singularity structure resulting singlet axial-vector is explained from factorization, defining finite remainder function.
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2021
ISSN: ['0370-2693', '1873-2445']
DOI: https://doi.org/10.1016/j.physletb.2021.136223