On the choice of beam polarization in $$e^+e^-\rightarrow ZZ/Z\gamma $$ e + e - → Z

Abstract

The anomalous trilinear gauge couplings of Z and γ are studied in e + e − → Z Z/Z γ with longitudinal beam polarizations using a complete set of polarization asymmetries for the Z boson. We quantify the goodness of the beam polarization in terms of the likelihood and find the best choice of e − and e + polarizations to be (+0.16, −0.16), (+0.09, −0.10) and (+0.12, −0.12) for Z Z, Z γ and combined processes, respectively. Simultaneous limits on anomalous couplings are obtained for these choices of beam polarizations using Markov-Chain-Monte-Carlo (MCMC) for an e + e − collider running at √ s = 500 GeV and L = 100 fb −1 . We find the simultaneous limits for these beam polarizations to be comparable with each other and also comparable with the unpolarized beam case.

Probing the anomalous triple gauge boson couplings in e+e−→W+W− using WRahaman1, Singh2 2020Phys. Rev. DSelf Cite170100View full textAdd to dashboardCite

“…Owing to the t-channel process ( Fig. 1a) and absence of a u-channel process, like in ZV production [7,76], the W ± produced are not forward-backward symmetric. We include forward-backward asymmetry, defined as…”

“…Here we intend to study W W V anomalous couplings in e + e − → W + W − at √ s = 500 GeV and integrated luminosity of L = 100 fb −1 using the cross section, forward-backward asymmetry and 8 polarizations asymmetries of W − for a set of choices of longitudinally polarized e + and e − beams in the channel W − → l −ν l (l = e, µ) 1 and W + → hadrons. The polarization of Z and W are being used widely recently for various BSM studies [69][70][71][72][73][74][75] along with studies with anomalous gauge boson couplings [3,7,76,77]. Recently the polarizations of W/Z has been measured in W Z production at the LHC [78].…”

“…s = 500 GeV, L = 100 fb −All the marginalised 1D projection and 2D projections at 95 % C.L. from MCMC in triangular array for the effective operators (TeV −2 ) for a set of choice of beam polarizations for √ s = 500 GeV, L = 100 fb −1 using the binned observables.space defined as[76] …”

Probing anomalous gauge-Higgs couplings using Z boson polarization at e+e− colliders

“…Ref. [23] describes the formalism that connects all the spin observables of Z to the angular distribution of the leptons arising from its decay. Ref.…”

Unravelling the anomalous gauge boson couplings in ZW± production at the LHC and the role of spin-1 polarizations

“…[49] In this article we intend to study the WW Z anomalous couplings in ZW ± production at the LHC at √ s = 13 TeV using the cross section, forward backward asymmetry and polarizations asymmetries [47,[70][71][72][73][74][75] of Z and W ± in the 3l + E T channel. The polarization of Z and W have been used recently for various BSM studies [76][77][78][79][80][81][82] along with studies with anomalous gauge boson couplings [47,74,83,84]. Recently the polarizations of W ± /Z has been estimated in ZW ± production [43] at NLO in QCD and also been measured at the LHC [85].…”