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Presenter: Sejla Kuldija

Faculty Sponsor: Rafael Coelho Lopes de Sa

School: UMass Amherst

Research Area: Physics

Session: Poster Session 3, 1:15 PM - 2:00 PM, Auditorium, A3

ABSTRACT

This poster presents a study using the ATLAS measurement of the Higgs boson width published with the full Run-2 dataset at √s = 13 TeV (140 fb^-1), based on the off-shell production measurement in the H → ZZ decay channel. In this study, we re-evaluate the hypotheses on the Higgs couplings used by ATLAS to measure the total Higgs boson width using the κ-framework. The measured Higgs boson width and its associated uncertainty are evaluated under different assumptions for the coupling of the Higgs boson to gluons κ_g and to vector bosons κ_V. The study combines measurements in the H* → ZZ → 4ℓ and H* → ZZ → 2ℓ2ν decay channels and reinterprets them as indirect constraints on the Higgs boson branching ratio to BSM states using the H → ZZ channel only. The results are consistent with Standard Model expectations while still allowing room for potential new-physics contributions to the total width. Full profile likelihood results are presented using the neural simulation-based inference technique.