BSM Primary effects

by Sandeepan Gupta (IFAE)

Thursday 8 May 2014, 14:30 → 15:30 Europe/Madrid

IFAE Seminar room (IFAE)

While the predictions of the SM Lagrangian have by now all been tested, the experimental verification of the predictions of its dimension 6 extension are only begining, with the arrival of Higgs data. We first identify the BSM primary effects, the set of physical quantities, that give us the best way to constrain new physics. To generate these deformations at the dimension 6 level, other deformatoins are also generated in a correlated way because of the accidental symmetries at the dimension 6 level. We derive these correlations and thus the predictions of the dimension 6 Lagrangian. We show that, there are 8 primary effects related to Higgs physics and 2 related to the $\kaapa_\gamma$ and $\lambda_\gamma$ triple gauge couplings (TGC). Barring four fermion deformations, the rest of the important primary effects are related to breaking of gauge coupling universality in the couplings of the Z-boson to fermions, Higgs and the W boson, and these can be constrained by the $g^Z_1$ TGC and precision measurements at LEP. All other deformations are correlated to these BSM primary effects. We also discuss the RG evolution of the couplings related to these BSM primaries and the RG-induced constraints that can be derived when a weakly constrained coupling enters the RG of a strongly constrained one.