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9 papers found.
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Exceptional composite dark matter

-Yvette , France 3 , Mikael Chala We study the dark matter phenomenology of nonminimal composite Higgs models with S O (7) broken to the exceptional group G2. In addition to the Higgs, three pseudoNambu

Minimally extended SILH

Higgs boson compositeness is a phenomenologically viable scenario addressing the hierarchy problem. In minimal models, the Higgs boson is the only degree of freedom of the strong sector below the strong interaction scale. We present here the simplest extension of such a framework with an additional composite spin-zero singlet. To this end, we adopt an effective field theory ...

Confronting SUSY models with LHC data via electroweakino production

We investigate multi-lepton signals produced by ElectroWeakino (EWino) decays in the MSSM and the TMSSM scenarios with sfermions, gluinos and non Standard Model Higgses at the TeV scale, with dark matter due to electroweak-scale Binos. We recast the present LHC constraints on EWinos for these models and we find that wide MSSM and TMSSM parameter regions prove to be allowed. We ...

Composite Dark Sectors

We introduce a new paradigm in Composite Dark Sectors, where the full Standard Model (including the Higgs boson) is extended with a strongly-interacting composite sector with global symmetry group \( \mathcal{G} \) spontaneously broken to \( \mathrm{\mathscr{H}}\subset \mathcal{G} \). We show that, under well-motivated conditions, the lightest neutral pseudo Nambu-Goldstone bosons ...

LHC bounds on lepton number violation mediated by doubly and singly-charged scalars

Francisco del A guila 0 Mikael Chala 0 0 CAFPE and Dpto. de Fsica Teorica y del Cosmos, Universidad de Granada , E-18071, Granada, Spain The only possible doubly-charged scalar decays into two

Collider limits on leptophilic interactions

Leptophilic interactions can only be observed at the LHC in four-lepton final states. If these interactions are mediated by a resonance in the di-leptonic channel with renormalizable couplings, the mediator must have spin 1. We study the LHC reach for such a vector boson allowing for arbitrary couplings. We find that only couplings to muons can be probed at the LHC because lepton ...

The elusive gluon

We study the phenomenology of vector resonances in the context of natural composite Higgs models. A mild hierarchy between the fermionic partners and the vector resonances can be expected in these models based on the following arguments. Both direct and indirect (electroweak and flavor precision) constraints on fermionic partners are milder than the ones on spin one resonances. ...

Constraining dark sectors with monojets and dijets

We consider dark sector particles (DSPs) that obtain sizeable interactions with Standard Model fermions from a new mediator. While these particles can avoid observation in direct detection experiments, they are strongly constrained by LHC measurements. We demonstrate that there is an important complementarity between searches for DSP production and searches for the mediator itself, ...

From Tevatron’s top and lepton-based asymmetries to the LHC

We define a lepton-based asymmetry in semi-leptonic \( t\overline{t} \) production at the LHC. We show that the ratio of this lepton-based asymmetry and the \( t\overline{t} \) charge asymmetry, measured as a function of the lepton transverse momentum or the \( t\overline{t} \) invariant mass is a robust observable in the Standard Model. It is stable against higher order ...