Effective field theory for new physics in top production and decays

Author : Celine Degrande

References :

• S. Willenbrock and C. Zhang, ​arXiv:1008.3869 [hep-ph]
• C. Degrande et al., ​arXiv:1010.6304 [hep-ph]

Description

This MadGraph5 model is the implementation of the top effective field theory described in ​arXiv:1008.3869 [hep-ph]. Namely, the model contains all the dimension six operators that are interfering with the leading tree-level SM amplitude for the top decay and both single top and top pair productions. This model is particularly suited to study the largest effects of non-resonant new physics (e.g. composite top and Higgs) in a model independent way. All the four-fermion operators are flavor diagonal and universal for the two lightest generations.

The four-fermion operators have been implemented using heavy vectors since they are not yet available in MadGraph5. In consequence, the model should not be used for other processes than the top decay and single top and top pair productions because it can contain extra operators. For example, a heavy vector coupled to tt and dd will induce a ttdd vertex as well as a 4-top one.

Futher information can be found in the note included in the model directory.