Federica Pasquali, PhD at Nikhef, will defend her thesis Tuesday 5 March 2024 at 13.00 at the University of Amsterdam
“The simplicity and complexity of the Higgs boson”
“Much like cats knocking down objects, particle physicists appreciate colliding protons. While cats run experiments with gravity, our inquiries aim in proving or disproving the existing theories about how the subatomic world works.
The mathematical theory used to describe the subatomic world is called Standard Model (SM) and incorporates all the discoveries of elementary particles starting from the discovery of the electron in 1897, to the Higgs boson (H) in 2012. While this theory is validated and supported by a large number of experiments, one open question is whether the last-discovered particle is the one theorized by the SM, or something that just resembles it. This thesis contributes to this effort, by analyzing the Higgs boson decay into two W bosons, specifically the mode where the W bosons decay into different-flavor charged leptons.
Three different types of analyses extract information about the gluon-gluon fusion (ggF) and vector-boson fusion (VBF) production modes. The first study selects ggF events with two additional jets to constrain the charge-parity properties of the effective Higgs-gluon interaction. The second analysis determines coupling strengths and cross-sections of the Higgs-boson in the ggF and VBF modes. The cross-section measurements are refined in the third study, where specific phase-space regions are considered separately contributing to the wider Simplified Template Cross Section effort. The results improve the uncertainties of previous analysis and agree with the predictions of the Standard Model. For the first time, the VBF production was observed with a significance of 5.8 standard deviations.”
“The simplicity and complexity of the Higgs boson: Couplings, Simplified Template Cross Sections and CP properties in the H->WW decay channel” (pdf)
The PhD defense will take place on Tuesday 5 March 2024, at 13.00 in the Agnietenkapel, Oudezijds Voorburgwal 229 – 231, 1012 EZ Amsterdam.
More information and link for the livestream on the website of the UvA.
Supervisors: prof. dr. W. Verkerke and prof. dr. ing. B. van Eijk
Co-supervisors: prof. dr. P. Ferrari
contact: Federica Pasquali