Scalar one-loop integrals for QCD
نویسنده
چکیده
We construct a basis set of infra-red and/or collinearly divergent scalar oneloop integrals and give analytic formulas, for tadpole, bubble, triangle and box integrals, regulating the divergences (ultra-violet, infra-red or collinear) by regularization in D = 4− 2ǫ dimensions. For scalar triangle integrals we give results for our basis set containing 6 divergent integrals. For scalar box integrals we give results for our basis set containing 16 divergent integrals. We provide analytic results for the 5 divergent box integrals in the basis set which are missing in the literature. Building on the work of van Oldenborgh, a general, publicly available code has been constructed, which calculates both finite and divergent one-loop integrals. The code returns the coefficients of 1/ǫ2, 1/ǫ1 and 1/ǫ0 as complex numbers for an arbitrary tadpole, bubble, triangle or box integral.
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