Two-loop Soft Anomalous Dimensions with Massive and Massless Quarks
نویسنده
چکیده
I present results for two-loop soft anomalous dimensions, which are derived from dimensionally regularized diagrams with eikonal quark lines and control soft-gluon emission in hard-scattering processes. Detailed results for the UV poles of the eikonal integrals are shown for massive quarks, and the massless limit is also taken. The construction of soft anomalous dimensions at two-loops allows soft-gluon resummations at NNLL accuracy.
منابع مشابه
Two-loop soft anomalous dimensions and next-to-next-to-leading-logarithm resummation for heavy quark production.
I present results for two-loop soft anomalous dimensions for heavy quark production which control soft-gluon resummation at next-to-next-to-leading-logarithm accuracy. I derive an explicit expression for the exact result and study it numerically for top quark production via e(+)e(-)-->tt, and I construct a surprisingly simple but very accurate approximation. I show that the two-loop soft anomal...
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