Phenomenology of the Supersymmetric Large Extra Dimensions scenario

The idea that the universe is trapped on a membrane in some high-dimensional spacetime may explain why gravity is so weak, and could be tested at high-energy particle accelerators. There is great freedom in the choice of extra-dimensional models which can be built to achieve this, but one class of models is of particular interest: Supersymmetric Large Extra Dimension scenario (SLED). This is because it can provide a framework in which the cosmological constant problem could be solved. The goal of this talk is to briefly introduce the fundamental features involved in the SLED scenario and to discuss more closely its experimental test at the LHC. To this end, we first consider a general extra-dimensional scalar that appears  in SLED as a graviton superpartner and examine the sensitivity of the ATLAS detector to the bulk scalar couplings with quarks and gluons. Next, we identify the lowest-dimension interaction which is possible between Standard Model brane fields and this bulk scalar. This lowest-dimensional interaction is unique and exclusive to SLED models and involves a trilinear coupling between a Standard Model Higgs and the bulk scalar. We again identify the sensitivity of the ATLAS detector to such a coupling. We finally compute its influence on Higgs physics at the LHC.