Non-abelian Infra-red Cancellations in the Unintegrated Nlo Kernel. *
نویسنده
چکیده
We investigate the infrared singularity structure of Feynman diagrams entering the next-to-leading-order (NLO) DGLAP kernel (nonsinglet). We examine cancellations between diagrams for two gluon emission contributing to NLO kernels. We observe the crucial role of color coherence effects in cancellations of infra-red singularities. Numerical calculations are explained using analytical formulas for the singular contributions. Submitted To Acta Physica Polonica B PACS numbers: 12.38.-t, 12.38.Bx, 12.38.Cy
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