Related papers: 331 Models and Bilepton Searches at LHC
We consider extensions of the Standard Model by vectorlike leptons and set limits on a new charged lepton, $e_4^\pm$, using the ATLAS search for anomalous production of multi-lepton events. It is assumed that only one Standard Model lepton,…
An extension of the Standard Model is presented that leads to the possible existence of new gauge bosons with masses in the range of a few TeV. Due to the fact that their couplings to Standard Model fermions are strongly suppressed, it is…
In type II seesaw utilized to explain the observed neutrino masses and mixings, one extends the Standard Model (SM) by introducing scalar fields which transform as a triplet under the electroweak gauge symmetry. New scalar couplings…
We perform a study of the charged Higgs production from an $SU(3)_{C}\otimes SU(3)_{L}\otimes U(1)_{X}$ model with right-handed neutrinos, postulating a custodial symmetry which reduces the number of free parameters in the scalar potential.…
The Standard Model of electroweak interactions has one scalar doublet. The minimal extension of this sector is effected by adding a neutral, singlet scalar field. Depending on whether the singlet field has a non-zero vacuum expectation…
The minimal supersymmetric standard model, and extensions, have stringent upper bounds on the mass of the lightest Higgs boson if perturbativity up to the Planck scale is assumed. We argue that these bounds are softened tremendously if the…
We consider a class of minimal anomaly free $\mathrm{U}(1)$ extensions of the Standard Model with three generations of right-handed neutrinos and a complex scalar. Using electroweak precision constraints, new 13 TeV LHC data, and…
By considering the 3-3-1 and the left-right symmetric models as low energy effective theories of the $SU(3)_C\otimes SU(3)_L\otimes SU(3)_R$~(for short $[SU(3)]^3$) gauge group, alternative versions of these models are found. The new…
We study a simple effective field theory incorporating six heavy vector bosons together with the standard-model field content. The new particles preserve custodial symmetry as well as an approximate left-right parity symmetry. The enhanced…
We present an update of the global fit of the Standard Model electroweak sector to latest experimental results. We include new kinematic top quark and $W$ boson mass measurements from the LHC, a $\sin^2\theta^{\ell}_{\mathrm{eff}}$ result…
In this work, we derive lower mass bounds on the Z' gauge boson based on the dilepton data from LHC with 13 TeV of center-of-mass energy, and forecast the sensitivity of the High-Luminosity-LHC with $L=3000 fb^{-1}$, the High-Energy LHC…
The Higgs boson could provide the key to discover new physics at the Large Hadron Collider. We investigate novel decays of the Standard Model (SM) Higgs boson into leptophobic gauge bosons which can be light in agreement with all…
A search for the associated production of the Higgs boson with a top quark pair is performed in multilepton final states using 20.3 fb$^{-1}$ of proton-proton collision data recorded by the ATLAS experiment at $\sqrt{s}=8$ TeV at the Large…
Extensive searches for Higgs bosons and other new phenomena predicted by extensions of the Standard Model have been performed at LEP. A summary is given reviewing the principal aspects and presenting a selection of results.
Extending the Standard Model by adding a scalar field transforming as a septet under $SU(2)_L$ preserves the $\rho$ parameter at tree level and can satisfy experimental constraints on the electroweak parameters $S$ and $T$. This work…
The static electromagnetic properties of the $W$ boson, $\Delta \kappa$ and $\Delta Q$, are calculated in the $SU_L(3)} \times U_X(1)$ model with right-handed neutrinos. The new contributions from this model arise from the gauge and scalar…
We have studied the branching ratios of doubly charged Higgs bosons at the LHC using a version of the SU(3)$_L\otimesU(1)_N$ electroweak model. At the end of this work we have made a very simple plotting comparating the total cross section…
After the discovery of a Higgs boson at the LHC, the next important step is to measure its couplings to fermions and bosons to unravel its true nature. In order to ultimately test the shape of the scalar potential that triggers the…
The D0 experiment has reported a direct search for a charged Higgs boson produced by $q \bar q$ annihilation and decaying to $t \bar b$ final state, in the $180 \leq M_{H^+} \leq 300$ GeV mass range. The analysis has lead to upper limits on…
We estimate the potential for observation at the LHC of a doubly charged Higgs boson, as predicted in Left-Right symmetric models. Single production by vector boson fusion, $W^+W^+ \to \Delta_{L,R}^{++}$ and pair production by the Drell-Yan…