%0 Journal Article
%T An Algorithm to Compute Born Scattering Amplitudes without Feynman Graphs
%A F. Caravaglios
%A M. Moretti
%J Physics
%D 1995
%I arXiv
%R 10.1016/0370-2693(95)00971-M
%X In this paper we suggest an {\it iterative} algorithm to compute automatically the scattering matrix elements of any given effective lagrangian, $\Gamma$. By exploiting the relation between $\Gamma$ and the connected Green function generator, $Z$, we provide a formula which does not require the use of the Feynman graphs and it is suitable to implement a numerical routine. By means of this algorithm we have built a relatively simple and fast fortran code which we have used to calculate, at the tree level, the rate of four fermion production at LEP I\negthinspace{I} (finding a very good agreement with previous calculation) with and without the emission of one observable photon.
%U http://arxiv.org/abs/hep-ph/9507237v1