Related papers: Leptophobic boson signals with leptons, jets and m…
In view of the recent and future electroweak precision data accumulated at LEP and SLC, we systematically analyze possible new physics effects that may occur in the leptonic sector within the context of $SU(2)_R \times SU(2)_L \times…
We analyze the anomalous quartic gauge boson couplings $WW\gamma\gamma$ and $ZZ\gamma\gamma$, described by dimension-6 effective quartic Lagrangian at the LHC. The sensitivities to anomalous quartic gauge couplings $a_{0,c}^{W,Z}/\Lambda^2$…
The tension among measurements of $V_{us}$ from different channels, the so-called Cabibbo Angle Anomaly, can be interpreted as a signal of lepton flavor universality (LFU) violation in the $W$ boson couplings. We investigate this issue in…
Stealth bosons are relatively light boosted particles with a cascade decay $S \to A_1 A_2 \to q \bar q q \bar q$, reconstructed as a single fat jet. In this work, we establish minimal extensions of the Standard Model that allow for such…
We study signals at the Large Hadron Collider (LHC) for Kaluza-Klein (KK) excitations of the electroweak gauge bosons in the framework with the Standard Model (SM) gauge and fermion fields propagating in a warped extra dimension. Such a…
The $Z'$-gauge boson in an $U(1)_{L_\mu-L_\tau}$ gauge symmetry has two interesting features: one is its vector couplings to the charged leptons, and the other is the decoupling from the electron. Based on these properties, we investigate…
In its second phase, LEP has allowed to study four fermion processes never observed before. Results are presented on the charged triple gauge boson couplings (TGC) from the W-pair, Single W and Single gamma production. The anomalous quartic…
We study a simple ultraviolet(UV) complete and anomaly free $Z'$ model based on a U$(1)'$ gauge family symmetry without introducing extra fermions beyond the standard model. The U$(1)'$ group is diagonal in the three family space in which…
We discuss a minimal solution to the long-standing $(g-2)_\mu$ anomaly in a simple extension of the Standard Model with an extra $Z'$ vector boson that has only flavor off-diagonal couplings to the second and third generation of leptons,…
A search is presented for narrow diboson resonances decaying to $WW$ or $WZ$ in the final state where one $W$ boson decays leptonically (to an electron or a muon plus a neutrino) and the other $W/Z$ boson decays hadronically. The analysis…
In the simplest little Higgs model the new flavor-changing interactions between heavy neutrinos and the Standard Model leptons can generate contributions to some lepton flavor violating decays of $Z$-boson at one-loop level, such as $Z \to…
We consider a new massive vector-boson Z' that couples to leptons through the L_mu - L_tau current, and to quarks through an arbitrary set of couplings. We show that such a model can be obtained from a renormalizable field theory involving…
A Fermiophobic Higgs boson can arise in models with an extended Higgs sector, such as models with scalars in an isospin triplet representation. In a specific model with a scalar triplet and spontaneous violation of lepton number induced by…
A Higgs particle produced in association with a Z boson and decaying into two photons is searched for in the data collected by the L3 experiment at LEP. All possible decay modes of the Z boson are investigated. No signal is observed in…
A leptophobic $Z^\prime$ that does not couple with the Standard Model leptons can evade the stringent bounds from the dilepton-resonance searches. In our earlier paper [T. Arun et al., Search for the $Z'$ boson decaying to a right-handed…
We demonstrate that the 8 multipole parameters describing the spin state of the $Z$ boson are able to disentangle known $Z$ production mechanisms and signals from new physics at the LHC. They can be extracted from appropriate asymmetries in…
Fermion masses may arise via mixing of elementary fermions with composite fermions of a strong sector in scenarios of strongly-coupled electroweak symmetry breaking. The strong sector may contain leptoquark states with masses as light as…
If a new $Z'$ is discovered with a mass $\sim 1 \ TeV$ at LHC/SSC, its (rare) decays into two charged leptons plus missing transverse energy will probe the $Z'$ coupling to the lepton doublet $(\nu,e)_L$ and to $W^+W^-$, allowing further…
We study the possibility of generating the observed baryon asymmetry via leptogenesis in the decay of heavy Standard Model singlet fermions which carry lepton number, in a framework without Majorana masses above the electroweak scale. Such…
The long-standing anomaly in the anomalous magnetic moment of the muon indicates the presence of chirality violating new physics contributions. A possible solution involves scalar leptoquarks with left- and right-handed couplings to the top…