Seminar: ‘Differential observables for the Higgs-strahlung process to all orders in EFT’

Title: ‘Differential observables for the Higgs-strahlung process to all orders in EFT.’

Speaker: Sourav Bera from Tata Institute of Fundamental Research (TIFR)

Venue&Time: Red Room / 15:00

Abstract: We develop methods to obtain the fully differential cross-section for the  f f \to Z(ll) h  process to any desired order in  effective field theory (EFT). To achieve this, we first derive a mapping between the partial wave expansion and the EFT expansion  to all orders. We find that at lower orders,  EFT predicts correlations between the different partial wave coefficients. This allows us to construct linear combinations of partial wave coefficients that get their leading contributions from a higher dimension EFT operator. We then introduce experimental observables, the so called angular moments — that   probe these  linear combinations of partial wave coefficients — and can be determined from a fully differential analysis of the angular distribution of the leptons arising from the Z – decay. We show that  analysing the dependence of these angular moments on the Zh invariant mass allows us to systematically probe all higher dimension EFT operators contributing to this process. In particular, we discuss how our results can be used to probe dimension-8 operators  in the Standard Model EFT (SMEFT). While we take  the Higgs-strahlung process as an example, the methods developed here are completely general and can also be applied to other 2-to-2 collider processes.