Possible anomalous ZZγ and Zγγ couplings and Z boson spin orientation in e+e−→Zγ: The role of transverse polarization

On polarization parameters of spin-1 particles and anomalous couplings in $$e^+e^-\rightarrow ZZ/Z\gamma $$ e + e - → Z Z / Z γ

“…2 for completeness. Eight polarization parameters for a massive spin-1 particle have been discussed earlier in the context of anomalous trilinear gauge couplings [47,48], for the spin measurements studies [46] and to study processes involving W ± bosons [49]. In this work we will investigate all anomalous couplings (up to dimension-6 operators) of Eq.…”

IsolatingCP-violatingγZZcoupling ine+e−Ananthanarayan1, Garg2, Patra3 et al. 2012Phys. Rev. D200420View full textAdd to dashboardCite

“…Of special significance is the construction presented in Refs. [29,30] of the formalism of a general spin-1 density matrix for the Z-boson spin orientation introduced in the context of CP-conserving anomalous couplings. It would be of interest to see if this can be extended to the case of CP-violating anomalous couplings and so explore the possibility of using this formalism to obtain bounds on such couplings as we have done here.…”

New physics in e + e − → Zγ at the ILC with polarized beams: explorations beyond conventional anomalous triple gauge boson couplings

“…The individual values of these triple gauge boson couplings (TGCs) as described before are zero at tree level in the SM, with non-zero values arising at higher orders or in composite models. These anomalous couplings have been extensively studied in the literature in the context of different colliders 1 [11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Moreover there has been a lot of work in the literature [8,10,13,17,23] where effective Lagrangians or effective momentum-space vertices and the associated form factors in neutral gauge boson production have been discussed.…”

“…The corresponding matrix element for the process of eq. (2.1) in the presence of contact interactions will be of the form: 19) where M 1,2 are defined before in eq. (2.9), and…”