Doctoral Candidate, Lisong Chen is defending a dissertation titled, "The study of the electroweak standard model precision physics at future electron-positron colliders” on Thursday, May 5th at 2;00pm (est). The dissertation was advised by Dr. Ayres Freitas (chair/advisor). 

The study of the electroweak standard model precision physics at future electron-positron colliders

Abstract: Future electron-positron colliders, such as the CEPC, FCC-ee, and ILC, usher in a new precision frontier where the electroweak (EW) sector of the Standard Model (SM) of particle physics can be scrutinized unprecedentedly, thereby unraveling the potential new physics beyond the Standard Model. For this purpose, one needs a deeper understanding of the SM, which is led by calculating radiative corrections to various well-defined observables, namely the electroweak precision observables (EWPOs) in the EW sector. However, to compare the EWPOs predicted by the theory with what was measured in the experiments, other ingredients contributing to the relevant cross section, such as the initial and final-state QED and QCD radiation effects, background contributions,  acceptance of the detector, and the selection of cuts, also need to be taken into account. In this talk, I will first report the recently accomplished three-loop EW corrections to some important EWPOs. Secondly, I will introduce a new software package GRIFFIN (Gauge-invariant Resonance In Four-Fermion Interactions), which aims to study the gauge resonance, such as the Z-boson resonance, in a theoretically well-controlled and manifestly gauge-invariant way where the issues aforementioned are addressed.