8 research outputs found
Automated calculation of one-loop processes within MadGolem
In the current LHC era, a vast number of models for BSM physics are being tested. For
predictions accurate enough to match experimental errors, theoretical calculations have
to go beyond LO estimates. However, calculating one-loop corrections in BSM models
involves many new particles with specific model dependent properties. Therefore, they
are done largely by hand, or in partially–automated ways. I present a fully automated
tool for the calculation of generic massive one-loop Feynman diagrams with four
external particles, implemented as a module within the fully automated MadGolem
framework. With this one can compute the NLO–QCD corrections to generic BSM
heavy resonance production processes, for example in the context of supersymmetric
theories
Modern Feynman Diagrammatic One-Loop Calculations
In this talk we present techniques for calculating one-loop amplitudes for
multi-leg processes using Feynman diagrammatic methods in a semi-algebraic
context. Our approach combines the advantages of the different methods allowing
for a fast evaluation of the amplitude while monitoring the numerical stability
of the calculation. In phase space regions close to singular kinematics we use
a method avoiding spurious Gram determinants in the calculation. As an
application of our approach we report on the status of the calculation of the
amplitude for the process .Comment: 10 pages, 2 figures; contribution to the proceedings of the CPP2010
Workshop, 23-25 Sep. 2010, KEK, Tsukuba, Japa
Recent Progress in the Golem Project
We report on the current status of the Golem project which aims at the
construction of a general one-loop evaluator for matrix elements. We construct
the one-loop matrix elements from Feynman diagrams in a highly automated way
and provide a library for the reduction and numerically stable evaluation of
the tensor integrals involved in this approach. Furthermore, we present
applications to physics processes relevant for the LHC.Comment: 7 pages, 4 figures, contrib. to proceedings of "Loops and Legs in
Quantum Field Theory", 10th DESY Workshop on Elementary Particle Theory,
25-30 April 2010, Woerlitz, German