Related papers: Fitting of Z' parameters
We discuss possibilities to measure the tt-gamma and ttZ couplings at hadron and lepton colliders. We also briefly describe how these measurements can be used to constrain the parameter space of models of new physics, in particular Little…
New observables for searching for Z' virtual states in processes e^+e^-\to\bar{f}f are proposed. They are based on the relations following due to renormalizability of an underlying theory between the parameters of the low-energy effective…
We study in a model-independent way new neutral and charged vector bosons that could give observable signals with leptonic final states at the LHC. We show, in particular, that a charged vector W' decaying into lepton plus neutrino is…
The couplings of the fermions to the Z boson are of great importance in establishing the validity of the Standard Model and in looking for physics beyond it. The couplings of the b-quark to the Z boson have been the subject of much…
Electroweak Precision Measurements are stringent tests of the Standard Model and sensitive probes to New Physics. Accurate studies of the $Z$-boson couplings to the first-generation quarks, which are currently constrained from LEP data to a…
This paper presents a search for a new Z' vector gauge boson with the ATLAS experiment at the Large Hadron Collider using pp collision data collected at $\sqrt{s} = 13$ TeV, corresponding to an integrated luminosity of 139 fb$^{-1}$. The…
A detailed analysis of ZZ production at the upgraded Fermilab Tevatron and the CERN Large Hadron Collider is presented for general ZZZ and ZZ\gamma couplings. Deviations from the Standard Model gauge theory structure for each of these can…
We consider the phenomenology of new neutral gauge bosons with flavour non-diagonal couplings to fermions, inherent in 6D models explaining successfully the hierarchy of masses as well as the mixing for quarks, charged leptons and neutrinos…
New physics models admit the interesting possibility of a Z' weak boson associated with an extra U(1) gauge symmetry and a Higgs boson that is heavy enough to decay into a pair of Z bosons. Then Z' production and decay via Z' -> ZH -> ZZZ…
Considering the constraints on the lepton flavor violating (LFV) couplings of the new gauge boson $Z'$ to ordinary leptons from the experimental upper limit for the LFV process $\ell\rightarrow 3\ell'$, we calculate the contributions of…
We reanalyse the potential of the LHC to discover new $Z'$ gauge bosons and to discriminate between various theoretical models. Using a fast LHC detector simulation, we have investigated how well the characteristics of $Z'$ bosons from…
We study the sensitivity of top pair production at the Large Hadron Collider (LHC) to the nature of an underlying Z' boson, including full tree level standard model background effects and interferences while assuming realistic final state…
We perform a multi-parameter global analysis of all data available till date from the ATLAS, CMS and Tevatron experiments, on the signals of a Higgs boson, to investigate how much scope exists for departure from the standard model…
We examine the production of a new $Z'$ gauge boson in association with photons or jets at future hadron supercolliders as a probe of its couplings to fermions. Associated jet production is found to be rather insensitive to these couplings…
With center of mass energies up to 209 GeV of LEP II, massive W and Z bosons can be produced in pairs and jointly with photons. This allows to study boson-boson couplings. Since the W and Z bosons are unstable and decay into fermions, two-…
Considering the constraints of the lepton flavor violating (LFV) processes $\mu \rightarrow 3e$ and $\tau\rightarrow3\mu$ on the LFV couplings $Z'\ell_{i}\ell_{j}$, in the contexts of the $E_{6}$ models, the left-right (LR) models, the…
A study of the Standard Model (SM) three electroweak boson production, $WV\gamma$ where V = W or Z gauge boson, is presented concerning events with a leptonically decaying W boson accompanied by a photon and two or more jets. We are using…
We study collider phenomenology of a leptophobic $Z'$ boson existing in eight scenarios of the $E_6$ grand unified theory, differing in particle embeddings. We first review the current bound on the $Z'$ mass $m_{Z'}$ based upon the LHC data…
The Z line shape is measured at LEP with an accuracy at the per mille level. Usually it is described in the Standard Model of electroweak interactions with account of quantum corrections. Alternatively, one may attempt different…
A search for heavy resonances that decay to tau lepton pairs is performed using proton-proton collisions at sqrt(s) = 13 TeV. The data were collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 2.2…