ar X iv : h ep - p h / 06 01 08 5 v 1 1 1 Ja n 20 06 Techniques for one - loop tensor integrals in many - particle processes
نویسندگان
چکیده
We briefly sketch the methods for a numerically stable evaluation of tensor one-loop integrals that have been used in the calculation of the complete electroweak one-loop corrections to e + e − → 4 fermions. In particular, the improvement of the new methods over the conventional Passarino–Veltman reduction is illustrated for some 4-point integrals in the delicate limits of small Gram (and other kinematical) determinants.
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