Related papers: Extra $W$-Boson Mass from a D3-Brane
A simple explanation of the W+dijet excess recently reported by the CDF collaboration involves the introduction of a new gauge boson with sizable couplings to quarks, but with no or highly suppressed couplings to leptons. Anomaly-free…
Classical solutions describing strings endowed with an electric charge and carrying a constant electromagnetic current are constructed within the bosonic sector of the Electroweak Theory. For any given ratio of the Higgs boson mass to W…
A systematic approach is followed in order to identify realistic D-brane models at toric del Pezzo singularities. Requiring quark and lepton spectrum and Yukawas from D3 branes and massless hypercharge, we are led to Pati-Salam extensions…
The Dark Abelian Sector Model (DASM) is an extension of the Standard Model of particle physics with an additional spontaneously broken $U_\text{d}(1)$ gauge symmetry connected to a dark sector, i.e. the SM particles do not carry the…
In this paper, motivated by the recent discovery of a Higgs-like boson at the LHC with a mass m_H\simeq 126 GeV, we review different models where the hierarchy problem is solved by means of a warped extra dimension. In the Randall-Sundrum…
We present a new complete analysis of the electroweak precision observables within the recently proposed 4-site Higgsless model, which is based on the SU(2)_L x SU(2)_1 x SU(2)_2 x U(1)_Y gauge symmetry and predicts six extra gauge bosons,…
The ATLAS collaboration has reported excesses in diboson invariant mass searches of new resonances around 2 TeV, which might be a prediction of new physics around that mass range. We interpret these results in the context of a modified…
We discuss some cosmological implications of extensions of the Standard Model with hidden sector scalars coupled to the Higgs boson. We put special emphasis on the conformal case, in which the electroweak symmetry is broken radiatively with…
We report on progress towards constructing string models incorporating both realistic D-brane matter content and moduli stabilisation with dynamical low-scale supersymmetry breaking. The general framework is that of local D-brane models…
We point out that the rare decay mode $W^{\pm} \rightarrow \gamma + D^{\pm}_{s} $ could be spectacularly enhanced, with a branching ratio around $10^{-6} $ which is three order of magnitude larger than previous predictions. Its observation…
We derive the Lagrangian and Feynman rules up to bilinear scalar fields for the mixed Higgs-radion eigenstates interacting with Standard Model particles confined to a 3-brane in Randall-Sundrum warped geometry. We use the results to compute…
The perturbative leading order open string three-point couplings for the Standard Model with hidden USp(6) on fractional D6-branes on T6/Z6' from arXiv:0806.3039 [hep-th], arXiv:0910.0843 [hep-th] are computed. Physical Yukawa couplings…
A new physical origin for electroweak symmetry breaking is proposed, involving compact spatial dimensions of scale 1/R \approx 1 TeV. The higher dimensional theory is supersymmetric, and hence requires the top-quark Yukawa coupling to be…
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…
The study of electroweak boson pair production provides a powerful test of the spontaneously broken gauge symmetry of the Standard Model (SM) and can be used to search for new phenomena beyond the SM. Extra neutral vector bosons $Z'$…
We present electroweak physics results from the D0 and CDF experiments using data from p \bar p collisions at \sqrt s = 1.8 TeV. Measurements of the cross sections times branching ratios for W and Z production, the inclusive width of the W…
Charged Higgs bosons are common predictions in most extensions of the Standard Model (SM) Higgs sector. Therefore, their observation would elucidate the nature of the Higgs sector. Motivated by the ATLAS collaboration's latest analysis…
We have investigated the boson sector in an extended standard model (SM) with additional $U(1)_D$ symmetry. In the proposed model, the singlet scalar and doublet scalar Higgs are added in addition to the SM-like scalar Higgs. These scalars…
As described previously, in SU(5) gauge theory with massless left-handed $ {\bf 5 \oplus 15 \oplus 40 \oplus 45^*}$ fermions \{QUD\}, an S-Matrix is produced by infra-red anomaly dynamics that might provide an extraordinarily economic…
We study the production of three electroweak gauge bosons at the LHC, in the effective field theory of the standard model, at dimension six and next-to-leading order in QCD. We present results for inclusive cross-sections and differential…