Anomalous quartic electroweak gauge-boson interactions
Description of the models:
We concentrate on anomalous quartic interaction among the electroweak gauge bosons that do not have a triple vertex associated to it. We describe these interactions using dimension eight effective operators assuming that the recently observed Higgs boson belongs to a SU(2)L doublet; see the file quartic.pdf for further details. This model is an extension of the Standard Model (SM) implemented at http://feynrules.irmp.ucl.ac.be/wiki/StandardModel; for further details see this link.
The model labeled SM_LS0_LS1 contains the standard model interactions supplemented by the dimension eight operators LS,0 and LS,1 defined in the file quartic.pdf. These dimension eight effective operators modify the vertices WWWW, WWZZ, and WWZZ that can be a simple re-scaling of the SM quartic interaction for a suitable choice of couplings.
The model labeled SM_LT8_LT9 contains the standard model interactions supplemented by the dimension eight operators LT,8 and LT,9 defined in the file quartic.pdf. These dimension eight effective operators give rise to anomalous AAAA, AAAZ, AAZZ, AZZZ, and ZZZZ vertices.
The model files include the quartic and SM vertices in the unitary gauge. To generate further models use the notebooks quartic_ls01.nb or quartic_lt89.nb as exemples and include the additional interactions that are already defined in the model file quartic.fr. The anomalous couplings are set to 1 GeV-4 by default, thus they should be conveniently chosen before the event generation .