== Effective field theory for nTGC ==

Author : Celine Degrande

References :

    * C. Degrande, A basis of dimension-eight operators for anomalous neutral triple gauge boson interactions, arXiv:1308.6323 


== Description ==

This !MadGraph5 model is the implementation of the dimension-eight operators inducing neutral triple gauge boson couplings (nTGC). Namely, the model contains all the four dimension-eight operators that modify the neutral 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. $C_i/\Lambda^4$ and are in TeV$^-2$. The name are self-explanatory, $C_{\widetilde{B}W}/\Lambda^4$ is called CBtWL4, $C_{BW}/\Lambda^4$ is called CBWL4 and similarly for $C_{WW}$ and $C_{BB}$. The new interaction has also an order NP (for new physics) which is the power of ($1/\Lambda^4$) of the amplitude. 

|| '''Operator''' ||'''Coefficient'''|| '''param_card name''' || '''limit at 95% C.L.(TeV$^{-4}$)''' ||
||'''$i H^\dagger \widetilde{B}_{\mu\nu}W^{\mu\rho}\{D_\rho,D^\nu\} H$'''|| '''$C_{\widetilde{B}W}/\Lambda^4$''' || CBtWL4 || [-47 , 47] ||
||'''$i H^\dagger B_{\mu\nu}W^{\mu\rho}\{D_\rho,D^\nu\} H$'''|| '''$C_{BW}/\Lambda^4$''' || CBWL4 || [-114 , 113 ] ||
||'''$i H^\dagger W_{\mu\nu}W^{\mu\rho}\{D_\rho,D^\nu\} H$'''|| '''$C_{WW}/\Lambda^4$''' || CWWL4 || [-45 , 48] ||
||'''$i H^\dagger B_{\mu\nu}B^{\mu\rho}\{D_\rho,D^\nu\} H$'''|| '''$C_{BB}/\Lambda^4$''' || CBBL4 || [-99  , 101] ||

The limits have been obtained by inverting the values of the anomalous couplings from the PDG 2012 and JHEP 1301 (2013) 063.