Related papers: Z' indication from new APV data in Cesium and sear…
A new era in particle physics is being spurred on by new data from the Large Hadron Collider. Non-vanishing neutrino masses represent firm observational evidence of new physics beyond the Standard Model. An extension of the latter, based on…
$Z^\prime$ boson as a new gauge boson has been proposed in many new physics models. The interactions of $Z^\prime$ coupling to fermions are detailed studied at the large hadron collider. A $Z^\prime$ with the mass of a few TeV has been…
We investigate the forward-backward asymmetries in the pair production of fourth family fermions through the new Z' interactions in the e+e- collisions. The Z' boson having family universal couplings can contribute to the pair production of…
We review the current status of the study of parity and time invariance violation in atoms, nuclei and molecules. We focus on parity non-conservation in cesium and three of the most promising areas of research: (i) parity non-conservation…
This is a short review of present and future limits on new neutral gauge bosons, in particular on hadrophilic or leptophobic $Z'$s recently proposed to interpret the observed fluctuations of $\Gamma _{c,b}$ at LEP. Light gauge bosons…
Heavy neutral gauge boson $Z^\prime$ is proposed in many new physics models. It has rich phenomena at the future muon collider. We study the properties of $Z^\prime$ boson with the process of $\mu^+ \mu^- \rightarrow q \bar{q}$, $\mu^+…
The LHC has provided an unprecedented amount of proton-proton collision data, bringing forth exciting opportunities to address fundamental open questions in particle physics. These questions can potentially be answered by performing…
The mixing of a new $Z'$ boson with the $Z$ significantly improves the fit to the LEP precision electroweak data, provided that the $Z'$ couples mainly to quarks. If $M_{Z_2}<200$~GeV, the $s$-channel $Z_2$ production and $(W,Z,\gamma)Z_2$…
We show in this letter how a heavy $(\mathcal{O}(TeV))$ invisible $Z'$ gauge boson that will practically be out of reach of the Large Hadron Collider (LHC), can be discovered at the future muon collider. The new force carrier has a…
The proposed Large Hadron Electron Collider (LHeC), with center-of-mass energy of $\sqrt{s}\approx 1.3$ TeV, provides a clean and sensitive environment to probe the top quark's neutral current interactions with the $Z$ boson via the process…
We investigate the sensitivity of top pair production to the properties of different Beyond the Standard Model theories embedding a new neutral boson. We include six-fermion decay, and account for the full tree-level Standard Model ttbar…
We investigate the possibility that four-fermion contact interactions give rise to the observed deviation from the Standard Model prediction for the weak charge of Cesium, through one-loop contributions. We show that the presence of loops…
New physics models predict the possibility of extra neutral gauge bosons ($Z'$) associated with an extra $U(1)'$ gauge symmetry. We study the couplings of the Higgs boson to the $Z$ boson and $Z'$ boson predicted by the new physics models.…
We present recent developments in the diagnostic study of heavy gauge bosons at future colliders with the emphasis on the determination of gauge couplings of $Z'$ to quarks and leptons. Proposed diagnostic probes at future hadron colliders…
A future $e^+e^-$ collider could run at the Z-pole to perform important electroweak (EW) precision measurements, while such a run may not be viable for a future muon collider. This however can be compensated by the measurements of other EW…
Exchange of two neutrinos (as well as other fermions) generates a long-range parity-violating (PV) potential of the form $\sim G^2/r^5$, with characteristic range $\hbar/(2m_\nu c)$. In atomic systems the corresponding matrix elements…
We study the impact of a leptophobic Z' gauge boson on the C_{1q} and C_{2q} parameters that describe the low-energy, parity-violating electron-quark neutral current interaction. We complement previous work by including the penguin-like…
The weak charge $Q_W$ measured in atomic parity violation experiments can receive compensating contributions from more than one new physics source. We show explicitly that the $\Delta Q_W$ contribution from the exchange of an extra Z-boson…
New heavy neutral gauge bosons Z' are predicted by many models of physics beyond the Standard Model. It is quite possible that Z's are heavy enough to lie beyond the discovery reach of the CERN Large Hadron Collider LHC, in which case only…
We present a fit to precision electroweak data in the standard model extended by an additional vector boson, Z', with suppressed couplings to the electron compared to the Z boson, with couplings to the b-quark, and with mass close to the…