Related papers: Dirac Gluinos in the Pyramid Scheme
In theories in which the parameters of the low energy theory are not unique, perhaps having different values in different domains of the universe as is possible in some inflationary models, the fermion masses would be distributed with…
Physical implications of a vector-like extension of the standard model for heavier quarks and leptons with $SU(2)\times U(1)$ gauge symmetry and only one Higgs doublet are discussed. This scheme incorporates infinitely many fermions, and…
Motivated by past and recent analyses we critically re-examine the use of effective lagrangians in the literature to constrain new physics and to determine the `physics reach' of future experiments. We demonstrate that many calculations,…
We examine constraints on a simple neutrino model in which there are three massless and three massive Dirac neutrinos and in which the left handed neutrinos are linear combinations of doublet and singlet neutrinos. We examine constraints…
Chiral-parity (parity-doublet) effective Lagrangian models provide a compact and symmetry-consistent framework for describing baryons and their negative-parity partners in terms of linearly-realized chiral symmetry. Unlike the conventional,…
Supersymmetric models with Dirac instead of Majorana gaugino masses have distinct phenomenological consequences. In this paper, we investigate the electroweakino sector of the Minimal Dirac Gaugino Supersymmetric Standard Model (MDGSSM)…
It has recently been proposed that all fundamental fermion masses (whether Dirac or Majorana) come from effective dimension-five operators in the context of a truly minimal left-right model. We show how a particularly economical scheme…
A Standard Model extension with two Majorana neutrinos can explain the measured neutrino masses and mixings, and also account for the matter-antimatter asymmetry in a region of parameter space that could be testable in future experiments.…
Supersymmetry is a prime candidate for physics beyond the Standard Model because low-energy supersymmetry stabilizes the Higgs mass avoiding fine-tuning and leads to natural electroweak symmetry breaking. However, searches at the Large…
Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models including both a light Higgs-like boson and massive spin-1 resonances are not in conflict with experimental constraints on the oblique S and…
It is widely thought that increasing bounds on the gluino mass, which feeds down to the stop mass through renormalization group running, are making a light stop increasingly unlikely. Here we present a counter-example. We examine the case…
We study the approximation of chiral quark models with simpler models, obtained via gradient expansion. The resulting Lagrangian of the type of the linear sigma-model contains, at the lowest level, an additional term with two derivatives.…
We propose the Supersymmetric Standard Models (SSMs) with a pseudo-Dirac gluino from hybrid $F-$ and $D-$term supersymmetry (SUSY) breakings. Similar to the SSMs before the LHC, all the supersymmetric particles in the Minimal SSM (MSSM)…
The masses of heavy baryons containing a b quark have been calculated numerically in lattice QCD with pion masses which are much larger than its physical value. In the present work we extrapolate these lattice data to the physical mass of…
The effective mass of phi meson at non-zero temperature is re-examined with an effective chiral Lagrangian. We find that the phi mass decreases with temperature but the effect is small compared to the result obtained from calculations using…
A relativistic hadronic model for nuclear matter and finite nuclei, which incorporates nonlinear chiral symmetry and broken scale invariance, is presented and applied at the one-baryon-loop level to finite nuclei. The model contains an…
We calculate the top quark loop corrections to the Zbb vertex in the chiral lagrangian of the dynamical electroweak symmetry breaking theory. We use the effective lagrangian based on coset space SU(2) X U(1) / U(1) with the gauge…
In this paper, we investigate how a sizeable width-to-mass ratio for a gluino, as is for example realized in GMSB scenarios, could affect the discovery potential of gluinos at the LHC. More importantly, the influence of the gluino being…
A large hierarchy of the Dirac masses can result in a small hierarchy for the low energy masses of the active neutrinos. This can happen even if the Majorana masses of right-handed neutrinos are all equal. A realistic description of the…
Radiative corrections with new heavy particles coupling to Higgs doublets destabilize the electroweak scale and require an ad-hoc counterterm cancelling the large loop contribution. If the mass scale m1 of these new particles in in the TeV…