Related papers: The Lightest Pseudo-Goldstone Boson at Future e+e-…
Pseudo Nambu-Goldstone bosons (pNGBs) are attractive dark matter (DM) candidates, since they couple to the Standard Model (SM) predominantly through derivative interactions. Thereby they naturally evade the strong existing limits inferred…
We analyze an extension of the Standard Model with an additional SU(2) hypercolor gauge group keeping the Higgs boson as a fundamental field. Vectorlike interactions of new hyperquarks with the intermediate vector bosons are explicitly…
We discuss the phenomenology of models of dynamical electroweak symmetry breaking which attempt to generate the observed fermion mass spectrum. After briefly describing the variety of and constraints on proposed models, we concentrate on…
We discuss the Next-to-Minimal Supersymmetric Standard Model (NMSSM) with a Peccei-Quinn (PQ) U(1) symmetry. When this symmetry is dynamically broken by the Higgs mechanism, the resulting pseudo-Nambu-Goldstone boson takes the role of an…
Recently a new class of models has emerged that addresses the naturalness problem of a light Higgs boson. In these ''little Higgs'' models, the Standard Model Higgs boson is a pseudo-Nambu-Goldstone boson of an approximate global symmetry.…
Light pseudoscalar mesons are Janus-type particles: Within quantum chromodynamics, they must be described as bound states of its fundamental degrees of freedom and as the (pseudo-) Goldstone bosons of its spontaneously broken chiral…
We consider cases where the dark matter-nucleon interaction is naturally suppressed. We explicitly show that by extending the standard model scalar sector by a number of singlets, can lead to a vanishing direct detection cross section, if…
In the E6 inspired composite Higgs model (E6CHM) the strongly interacting sector possesses an SU(6) global symmetry which is expected to be broken down to its SU(5) subgroup at the scale f > 10 TeV. This breakdown results in a set of…
Within the Bethe-Salpeter formalism for instantaneous interactions, we describe, along a totally analytic route, the lightest pseudoscalar mesons by quark-antiquark bound states which show at least three indispensable general features,…
We explore the leading effective interactions between the Standard Model and a generic singlet CP-odd (pseudo)Goldstone boson in two frameworks for electroweak symmetry breaking: linear and non-linear realizations, determining the basis of…
In the standard model extended by a single complex scalar boson with a softly broken global U(1) symmetry, a pseudo Nambu-Goldstone boson becomes a candidate for dark matter. In this paper, we discuss the direct detection of the pseudo…
We study the effective theory of a generic class of hidden sectors where supersymmetry is broken together with an approximate R-symmetry at low energy. The light spectrum contains the gravitino and the pseudo-Nambu-Goldstone boson of the…
We calculate the production rate of gauge-boson pairs at $e^+e^-$ colliders in a model with a ``hidden'' electroweak symmetry breaking sector - i.e. one in which there are a large number of particles in the symmetry breaking sector other…
Technicolor models with the GIM mechanism are successful solutions to common problems of technicolor model building. These models have a rich set of new particles and interactions. We present the spectrum of the lightest exotic particles in…
We describe a class of relativistic models incorporating finite density of matter in which spontaneous breakdown of continuous symmetries leads to a lesser number of Nambu-Goldstone bosons than that required by the Goldstone theorem. This…
In N=1 supersymmetric theories, quasi Nambu-Goldstone (QNG) bosons appear in addition to ordinary Nambu-Goldstone (NG) bosons when the global symmetry G breaks down spontaneously. We investigate two-body scattering amplitudes of these…
We study the vacuum alignment of the top-mode pseudo-Nambu-Goldstone boson Higgs (TMpNGBH) model, which has recently been proposed as a variant of the top quark condensate model in light of the 126 GeV Higgs boson discovered at the LHC. It…
We study the phenomenology of a light (GeV scale) sterile neutrino sector and the pseudo-Goldstone boson (not the majoron) associated with a global symmetry in this sector that is broken at a high scale. Such scenarios can be motivated from…
Axion-like particles (ALPs) are pseudo Nambu-Goldstone bosons of spontaneously broken global symmetries in high-energy extensions of the Standard Model (SM). This makes them a prime target for future experiments aiming to discover new…
We explain the recent diphoton excesses around $750$ GeV by both ATLAS and CMS as a singlet scalar $\Phi$ which couples to SM gluon and neutral gauge bosons only through higher dimensional operators. A natural explanation is that $\Phi$ is…