Description:

Abstract: The effective field theory (EFT) approach posits that in a scenario where new particles cannot be observed directly at low energy, the source of new physics are heavy fields beyond our current reach. The Standard Model (SM) Lagrangian contains fields of dimension-4 and the EFT framework extends the SM Lagrangian in an expansion in inverse powers of the scale of new physics. Within this framework, the potential impact of higher dimensional operators can be explored. The most common example of an EFT appears in the Fermi theory of weak interactions where the appearance of the four Fermi vertex features an operator of dimension-6. In this talk, I will provide an overview of EFT explorations at the LHC. With the collection of more than 150 fb$^{-1}$ of data at the LHC, rare processes predicted in the Standard Model have become accessible. These rare processes can be used as probes of new physics using the EFT framework. The large dataset also enables precision measurements of certain processes allowing the ability to study deviations from SM expectations and characterizing the nature of potential excesses within the EFT formalism. I will focus on the exploration of dimension-6 and dimension-8 operators at the LHC in final states arising out of the decay of multiple gauge bosons. I will provide a snapshot of LHC Run II analyses as we embark on Run III.

Speaker: Sapta Bhattacharya, Northwestern University 

Host: Michael Schmitt

This seminar will be offered in both in-person and virtual formats.