A simple method for multi-leg loop calculations
نویسندگان
چکیده
A simple algorithm is presented for the tensorial reduction of oneloop diagrams with massless external momenta. At most rank one tensor integrals with the initial number of denominators appear, plus, eventually, higher rank integrals with less denominators. The number of Gram determinants in the tensorial decomposition is then reduced, giving a better numerical stability of the results. In some cases, surprisingly simple expressions can be obtained, even for very complicated one-loop multi-leg diagrams. ∗email address: [email protected]
منابع مشابه
A simple method for multi-leg loop calculations 2: a general algorithm
The method introduced in a previous paper to simplify the tensorial reduction in multi-leg loop calculations is extended to generic one-loop integrals, with arbitrary internal masses and external momenta. CERN-TH/97-372 December 1997
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