Topics in Higgs Physics
Abstract
In this work, theoretical constraints are derived and experimental signatures for two classes of models of electroweak symmetry breaking are investigated. The first class comprises the CP-conserving Two -Higgs-Doublet (THD) Models, that is, models in which two elementary scalar doublet fields participate in the process of electroweak symmetry breaking and which respect the combined charge-conjugation and parity, or CP, symmetry. These models are examined in the context of the so-called "triviality" of theories with fundamental spinless particles. Quantum field theories are called trivial if they cannot be consistently defined at arbitrarily high energies unless they are non -interacting. The usual remedy is to regard them as effective theories valid only at energies lower than some finite cutoff energy scale. This allows for non-trivial interactions but constrains the range of possible values of the parameters of the theory. By requiring the THD Model to define a consistent effective theory for scales below a physically sensible cutoff--one that is several times larger than the highest mass of the problem--combined bounds are derived on the scalar particle masses and mixing angles. Subsequently, the focus herein is on the phenomenology of the CP-odd scalar of THD models. I explore the parameter space determined by triviality bounds and identify the regions where three different signatures of this particle can be detected at the Large Hadron Collider (LHC) that has been proposed for CERN. The second class of models investigated is that of a Non-Standard Higgs boson. These models have the same low-energy spectrum as the Standard Model, but, due to dynamics at higher energies, differ from it in the strength of the couplings of the Higgs particle to fermions and gauge bosons. Theoretical constraints that may arise in these models are discussed, and the prospects of detecting such a Non-Standard Higgs and distinguishing it from its Standard Model counterpart in future experiments at the LHC are investigated.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- January 1995
- Bibcode:
- 1995PhDT........45K
- Keywords:
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- HADRON COLLIDER;
- ELECTROWEAK SYMMETRY;
- Physics: Elementary Particles and High Energy