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Techniques for one-loop tensor integrals in many-particle processes

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 نشر من قبل Stefan Dittmaier
 تاريخ النشر 2006
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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 $PepPemto4 $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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