Related papers: Stringy origin of Tevatron Wjj anomaly
We present the most recent W and Z production, asymmetries, and V+jets results from the Tevatron collider at sqrt(s) = 1.96 TeV, analyzing data collected by CDF and DZero detectors between 2002-2011. The results include the measurements of…
We derive the leptonic neutral current in the simplest little Higgs model and compute the contribution of the model to the decay width $Z \to e^+e^-$. Using the precision electroweak data we obtain a strong lower bound $f\geq 5.6$ TeV at…
The $SU(3)_C X SU(3)_L X U(1)_X$ gauge model with the minimal scalar sector (two Higgs triplets) is studied in detail. One of the vacuum expectation values $u$ is a source of lepton-number violations and a reason for the mixing among the…
The discovery of neutrino masses has raised the importance of studies in the context of neutrinoless double beta decay, which constitutes a landmark for lepton number violation. The standard interpretation is that the light massive…
We propose a string-derived model based on the gauge group $SU(5)\times U(1)$ which satisfies the stringent constraints from no-scale supergravity, allows gauge coupling unification at the string scale, and entails previously unexplored…
Motivated by the recent update on LHC searches for narrow and broad resonances decaying into diphotons we reconsider the possibility that the observed peak in the invariant mass spectrum at M_{\gamma \gamma} = 750 GeV originates from a…
The minimal embedding of the Standard Model in type I string theory is described. The SU(3) color and SU(2) weak interactions arise from two different collections of branes. The correct prediction of the weak angle is obtained for a string…
We study models with heavy exotics that account for the LHC $750$ GeV diphoton excess in light of current vector-like quark bounds. Utilizing only exotics that may appear in three-stack and four-stack D-brane models, we show that a narrow…
We address the mass ranges of new neutral gauge bosons and constraints on the accompanying exotic particles as predicted by a class of superstring models. Under certain assumptions about the supersymmetry breaking parameters we show that…
In this report the SU(3)_C X SU(3)_L X U(1)_X gauge model with minimal scalar sector, two Higgs triplets, is presented in detail. One of the vacuum expectation values $u$ is a source of lepton-number violations and a reason for mixing among…
A search is presented for charge-asymmetric production of a W' boson that has been proposed to accommodate the forward-backward asymmetry observed in the production of top-antitop quark pairs at the Tevatron. The new heavy W' boson would be…
The gauge symmetry of the Standard Model is SU(3)_c x SU(2)_L x U(1)_Y for unknown reasons. One aspect that can be addressed is the low dimensionality of all its subgroups. Why not much larger groups like SU(7), or for that matter, SP(38)…
A general electroweak scale $Z'$ is applied in a supersymmetric SU(6)$\timesSU(2)_h$ grand unification model, to have a $\Z_6$ for the hexality. We briefly show that there cannot exist any baryonic U(1)$'_B$ in any subgroup of E$_6$. Any…
String theories in principle address the origin and values of the quark and lepton masses. Perhaps the small values of neutrino masses could be explained generically in string theory even if it is more difficult to calculate individual…
New charged vector bosons $W'$ decaying into gauge boson pairs $WZ$ are predicted in many scenarios of new physics, including models with an extended gauge sector (EGM). Due to the large variety of models (other unification groups, models…
The origin of tiny neutrino mass is a long standing unsolved puzzle of the Standard Model (SM), which allows us to consider scenarios beyond the Standard Model (BSM) in a variety of ways. One of them being a gauge extension of the SM may be…
A search is performed for narrow resonances decaying into $WW$, $WZ$, or $ZZ$ boson pairs using 20.3 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of $\sqrt{s}$ = 8 TeV recorded with the ATLAS detector at the Large…
A U(1)' or Z' is generic in many scenarios of physics beyond the Standard Model, such as string theory compactifications, GUTs, extra-dimensions, compositeness, dynamical electroweak symmetry breaking, dark-sector models, etc. We study the…
We consider a simple extension of the Standard Model (SM) with a vector-like lepton and a local $U(1)'$ symmetry, motivated by the recent experimental anomalies in the muon $g-2$ and the $W$ boson mass. The $U(1)'$ symmetry is spontaneously…
Results are presented from a search in the dijet final state for new massive narrow resonances decaying to pairs of W and Z bosons or to a W/Z boson and a quark. Results are based on data recorded in proton-proton collisions at $\sqrt{s} =$…