Magic Spinor Product Methods in Loop Integrals

by Bennie Ward (Baylor University and CERN)

Friday 10 Jun 2011, 14:00 → 15:00 Europe/Zurich

TH Theory Conference Room (CERN)

We present an approach to higher point loop integrals using Chinese magic in the virtual loop integration variable. We show, using the five point function in the important e^+e^-\to f\bar{f}+\gamma process for ISR as a pedagogical vehicle, that we get an expression for it directly reduced to one scalar 5-point function and 4-, 3-, and 2- point integrals, thereby avoiding the computation of the usual three tensor 5-pt Passarino-Veltman reduction. As a consequence, we present the attendant representation of this 5-pt scalar function in terms of lower point scalar functions. We argue that all of this offers potential for greater numerical stability.

Slides Ward.pdf Ward.pptx