Related papers: Doubling down on down-type diquarks
The LHC has not discovered any New Physics beyond the anticipated $h(125)$ boson, and new ideas abound for out-of-the-box searches, or Effective Field Theories with multi-TeV cutoff. But, have we exhausted dimension-4 operators involving…
We discuss the possibility that flavor hierarchies arise from the electroweak scale in a two Higgs doublet model, in which the two Higgs doublets jointly act as the flavon. Quark masses and mixing angles are explained by effective Yukawa…
Directly probing light-quark Yukawa couplings and their flavor structure remains a major challenge due to their smallness and overwhelming QCD backgrounds. In this Letter, we propose a theoretical framework to access these couplings at…
We present the results of an extensive analysis of flavour physics in both quark and lepton sectors, in the Littlest Higgs model with T-parity (LHT). In the quark sector, we identify some interesting scenarios for new mirror quark masses…
We analyse the interplay of the constraints imposed on flavour-symmetric Composite Higgs models by Naturalness considerations and the constraints derived from Flavour Physics and Electroweak Precision Tests. Our analysis is based on the…
We systematically study model-independent constraints on the three generic charged Higgs couplings to $b$-quarks and up-type quarks. While existing LHC searches have focussed on the $tb$ coupling, we emphasize that the LHC plays a crucial…
We construct a three-Higgs doublet model with a flavour non-universal ${\rm U}(1)\times \mathbb{Z}_2$ symmetry. That symmetry induces suppressed flavour-changing interactions mediated by neutral scalars. New scalars with masses below the…
Flavour- and CP-violating electromagnetic or chromomagnetic dipole operators in the quark sector are generated in a large class of new physics models and are strongly constrained by measurements of the neutron electric dipole moment and…
We study the impact of heavy vector-like leptons on several observables in collider and low-energy physics. These states, present in many well-motivated extensions of the Standard Model, can induce lepton flavour violation and non-standard…
We describe a model of quarks which identifies the large global symmetries of little Higgs models with the global flavor symmetries that arise in a deconstruction of the extra-dimensional 'topological insulator' model of flavor. The…
We study a class of nonstandard interactions of the newly discovered 125 GeV Higgs-like resonance that are especially interesting probes of new physics: flavor violating Higgs couplings to leptons and quarks. These interaction can arise in…
We study quark flavor violating interactions mediated by the Higgs boson $h$. We consider observables involving a third generation quark, of both the up and the down quark sectors, like $h\rightarrow bs$ and $t\rightarrow ch$. Using an…
We systematically explore ultraviolet complete models where flavour hierarchies emerge, via approximate accidental symmetries, from an underlying flavour non-universal gauge structure. In order to avoid large quantum corrections to the…
Di-Higgs couplings to fermions of the form $h^{2}\overline{f}f$ are absent in the Standard Model, however, they are present in several physics Beyond Standard Model (BSM) extensions, including those with vector-like fermions. In Effective…
An Effective Field Theory for dark matter at a TeV-scale hadron collider should include contact interactions of dark matter with the partons, the Higgs and the Z. This note estimates the impact of including dark matter-Z interactions on the…
We explored the possibility that Higgs coupling to new physics violates flavor universality. In particular, we parameterize such models with dimension-six effective operators which modify the coupling between the first generation quarks,…
Like many other models, Composite Higgs Models feature the existence of heavy vector-like quarks. Mixing effects between the Standard Model fields and the heavy states, which can be quite large in case of the top quark, imply deviations…
To study a flavour model with a non-minimal Higgs sector one must first define the symmetries of the fields; then identify what types of vacua exist and how they may break the symmetries; and finally determine whether the remnant symmetries…
We investigate the impact of flavour-conserving, non-universal quark-lepton contact interactions on the dilepton invariant mass distribution in $p~p \to \ell^+ \ell^-$ processes at the LHC. After recasting the recent ATLAS search performed…
Composite Higgs models with anarchic partial compositeness require a scale of new physics ${\cal O}(10-100)$ TeV, with the bounds being dominated by the dipole moments and $\epsilon_K$. The presence of anarchic bilinear interactions can…