Effective field theory for weak boson pair production

Author : Celine Degrande

References :

• C. Degrande, N. Greiner, W. Kilian, O. Mattelaer, H. Mebane, T. Stelzer, S. Willenbrock, C. Zhang, ​arXiv:1205.4231 [hep-ph]

Description

This FeynRules model is the implementation of the weak boson effective field theory described in ​arXiv:1205.4231 [hep-ph]. Namely, the model contains all the five dimension-six operators that modify the triple gauge boson vertices. Their coefficients can be set in the param_card.dat. The parameters in the param_card are the full coefficients, i.e.

 $c_i/\Lambda^2$ 

and are in TeV^-2. The name are self-explanatory,

 $c_{WWW}/\Lambda^2$ 

is called CWWWL2 and similarly for c_W and c_B , the coefficients of the CP violating operators

 $O_{\tilde{W}WW}\quad\text{and}\quad O_{\tilde{W}}$ 

are CPWWWL2 and CPWL2 respectively. The new interaction has also an order NP (for new physics) which is the power of

 $1/\Lambda$ 

of the amplitude. For example, an amplitude with one vertex for a dimension-six operator is proportional to

 $1/\Lambda^2$ 

and has NP=2.

Operator	Coefficient	param_card name	limit at 68% C.L.(TeV${-2}$)
$\mbox{Tr}[W_{\mu\nu}W^{\nu\rho}W_{\rho}^{\mu}]$	$c_{WWW}/\Lambda^2$	CWWWL2	[-11.9 , -1.94]
$(D_\mu\Phi)^\dagger W^{\mu\nu}(D_\nu\Phi)$	$c_{W}/\Lambda^2$	CWL2	[-8.42 , 1.44]
$(D_\mu\Phi)^\dagger B^{\mu\nu}(D_\nu\Phi)$	$c_{B}/\Lambda^2$	CBL2	[-7.9 , 14.9]
$\mbox{Tr}[\tilde{W}_{\mu\nu}W^{\nu\rho}W_{\rho}^{\mu}]$	$c_{\tilde{W}WW}/\Lambda^2$	CPWWWL2	[-185.3 , -82.4]
$(D_\mu\Phi)^\dagger \tilde{W}^{\mu\nu}(D_\nu\Phi)$	$c_{\tilde{W}}/\Lambda^2$	CPWL2	[-39.3 , -4.9]

The limits have been obtained by inverting the values of the anomalous couplings from the PDG 2012.