Journal Club

Seminar Room

Monday 17th of October, 2016

Hour: 10:00

Title: Confronting SUSY models with LHC data via electroweakino production

Presented by: Mikael Chala

Ref: https://arxiv.org/abs/1610.03822v1

Abstract:

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, being the Bino electroweak-scale dark matter. 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 forecast the number of events expected in the signal regions of the experimental multi-lepton analyses in the next LHC runs. The correlations among these numbers will help to determine whether future deviations in multi-lepton data are ascribable to the EWinos, as well as the supersymmetric model they originate from.

Hour: 10:00

Title: Cosmological Relaxation of the Electroweak Scale

Presented by: Roberto Vega-Morales

Ref: https://arxiv.org/abs/1504.07551v2

Abstract:

A new class of solutions to the electroweak hierarchy problem is presented that does not require either weak scale dynamics or anthropics. Dynamical evolution during the early universe drives the Higgs mass to a value much smaller than the cutoff. The simplest model has the particle content of the standard model plus a QCD axion and an inflation sector. The highest cutoff achieved in any technically natural model is 10^8 GeV.

Hour: 10:00

Title: Relaxation from particle production

Presented by: Roberto Vega-Morales

Ref: https://arxiv.org/abs/1607.01786v1

Abstract:

We consider using particle production as a friction force by which to implement a "Relaxion" solution to the electroweak hierarchy problem. Using this approach, we are able to avoid superplanckian field excursions and avoid any conflict with the strong CP problem. The relaxation mechanism can work before, during or after inflation allowing for inflationary dynamics to play an important role or to be completely decoupled.