טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentJonathan Cohen
SubjectContact Interactions in Higgs-Vector Boson Associated
Production at the ILC
DepartmentDepartment of Physics
Supervisors Professor Emeritus Eilam Gad
Dr. Bar Shalom Shaouly
Full Thesis textFull thesis text - English Version


Abstract

The Effective Field Theory (EFT) is a model-independent approach which parameterizes new interactions of the known Standard Model (SM) particles. The new interactions are then characterized by a new scale, which represents the scale of New Physics (NP). We use EFT to parameterize Beyond Standard Model (BSM) effects of NP in terms of higher dimensional operators. We focus on a certain class of dimension 6 operators called the 𝜓2𝜙2D operators, which are generated by heavy vector field exchanges in the underlying theory and couple two vector currents containing scalars and fermions. In particular, these operators induce new non-SM contact terms of the form   𝜓𝜓𝜙D𝜙. We then investigate the high-energy behavior of these new interactions, focusing on deviations from the SM in the Higgs-Vector boson associated production processes at a future International Linear Collider (ILC) ee- Zh ,Zhh and imposing bounds from Electro-weak precision measurements. The contact interactions naturally grow with energy, therefore, the validity of the EFT expansion is also adressed. We find a good agreement between the analytical analysis and the numerical simulations for both processes. In addition, we find an interesting correlation between hZ and hhZ signals which can be utilized in future NP searches in these channels. Finally, we show that the ILC is an excellent test ground for probing the NP scale associated to these effective operators via hZ & hhZ signals.