The Two-loop Anomalous Dimension Matrix for Soft Gluon Exchange

Aybat, S.Mert ; Dixon, Lance J. ; Sterman, George

Stanford Linear Accelerator Center

关键词: Quantum Chromodynamics;    71 Classical And Quantum Mechanics, General Physics;    Gluons;    Color;    Anomalous Dimension;   

DOI  :  10.2172/885280
RP-ID  :  SLAC-PUB-11907
RP-ID  :  AC02-76SF00515
RP-ID  :  885280

美国|英语

来源: UNT Digital Library

【 摘 要 】

The resummation of soft gluon exchange for QCD hard scattering requires a matrix of anomalous dimensions. We compute this matrix directly for arbitrary 2 {yields} n massless processes for the first time at two loops. Using color generator notation, we show that it is proportional to the one-loop matrix. This result reproduces all pole terms in dimensional regularization of the explicit calculations of massless 2 {yields} 2 amplitudes in the literature, and it predicts all poles at next-to-leading order in any 2 {yields} n process that has been computed at next-to-leading order. The proportionality of the one- and two-loop matrices makes possible the resummation in closed form of the next-to-next-to-leading logarithms and poles in dimensional regularization for the 2 {yields} n processes.