Double Higgs and ttX: Portals to New Physics
Dr. Andrew Brinkerhoff (ND PhD)
Assistant Professor of Physics
Ten years after discovering the Higgs boson, LHC scientists are still looking for some sign of physics beyond the Standard Model (BSM) in high-energy proton collisions. While most new physics searches focus on direct evidence for BSM particle production, Effective Field Theory (EFT) enables us to explore BSM effects even above the LHC collision energy of 13.6 TeV. The EFT approach uses measurements of SM particles to detect anomalies in their interactions, which could indicate BSM effects at some higher mass scale. I will present two CMS analyses which incorporate EFT interpretations: a search for double Higgs (HH) production, focusing on Higgs decays which produce multiple charged leptons; and a measurement of top pair production in association with a Z or Higgs boson (ttX) in events with a high-momentum "boosted" Z or H decaying to a bottom quark pair. These extremely rare interactions offer a unique opportunity to probe new physics related to the Higgs boson and top quark.