Related papers: Weak-Singlet Fermions: Models and Constraints
We derive constraints on the Randall-Sundrum scenario with the standard model fields in the bulk. These result from tree level effects associated with the deformation of the zero mode wave-functions of the W and the Z once electroweak…
We consider a model for the electroweak interactions based on the assumption that physical particles are singlets under the gauge group SU(2). The concept of complementarity explains why the standard model works with such an extraordinary…
The running weak mixing angle is used as a convenient tool to keep control of dominating logarithmic corrections in the Standard Model of the electroweak interactions connecting measurements at largely differing energy scales. To relate the…
Taking into account the negative results of direct searches for beyond the Standard Model fields and the consequent mass gap between Standard Model and possible unknown states, the use of electroweak effective theories is justified. Whereas…
We study technicolor models in which all of the technifermions are color-singlets, focusing on the case in these fermions transform according to the fundamental representation of the technicolor gauge group. Our analysis includes a…
Extensions of the MSSM often predict the existence of new fermions and their scalar superpartners which are vectorlike with respect to the standard model gauge group but may be chiral under additional gauge factors. In this paper we explore…
We discuss a test of the Standard Model fermion mass origin in models of dynamical electroweak symmetry breaking. The couplings of composite pseudoscalar resonances to top quarks allow to distinguish high-scale Extended-Technicolor-type…
In models with supersymmetry breaking by boundary conditions on an extra dimension it is possible to relate in a quantitative natural way the Fermi scale to the size of the extra dimension. We analyze in detail the compatibility of such…
The extension of the Standard Model with exotic quark singlets and doublets introduces large flavor changing neutral couplings between ordinary fermions. We derive inequalities which translate the precise determination of the diagonal Z…
The weak dipole moments of leptons and quarks, \ie those related to their $Z$--coupling, are reviewed. Standard Model predictions and experimental results may result in a stringent test for both their pointlike structure and also for the…
In this work we combine information from relic abundance, direct detection, cosmic microwave background, positron fraction, gamma rays, and colliders to explore the existing constraints on couplings between Dark Matter and Standard Model…
Building upon the fundamental partial compositeness framework we provide consistent and complete composite extensions of the standard model. These are used to determine the effective operators emerging at the electroweak scale in terms of…
A weak-doublet with hypercharge $-3/2$ is one of only a handful of fermions which has a renormalisable interaction with Standard Model fields. This should make it worthy of attention, but it has thus far received little consideration in the…
We review the available constraints on the low energy supersymmetry. The bulk of the electroweak data is well screened from supersymmetric loop effects, due to the structure of the theory, even with superpartners generically light, ${\cal…
We investigate the experimentally allowed parameter space of an extension of the standard model (SM3) by one additional family of fermions. Therefore we extend our previous study of the CKM like mixing constraints of a fourth generation of…
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite…
A singlet fermion which interacts only with a new singlet scalar provides a viable and minimal scenario that can explain the dark matter. The singlet fermion is the dark matter particle whereas the new scalar mixes with the Higgs boson…
We explore and contrast the capabilities of future colliders to probe the nature of the electro-weak phase transition. We focus on the real singlet scalar field extension of the Standard Model, representing the most minimal, yet most…
Serious searches for the weakly interacting massive particle (WIMP) have now begun. In this context, the most important questions that need to be addressed are: "To what extent can we constrain the WIMP models in the future?" and "What will…
Large fermionic multiplets appear in different extensions of the Standard Model (SM), which are essential to predict small neutrino masses, relic abundance of the dark matter (DM) and the measured value of muon anomalous magnetic moment…