Summary of physics doctoral thesis: Some new physical effects in the 3−2−3−1 and 3−3−3−1 models

Resolve the neutrino mass problem. Parameterize the parameters in the model 3−2−3−1 to seek for dark matter for each version of the model with q=0 and q=−1. Research for Z1 and Z01 at LEPII and LHC. Survey in detail the mass of gauge bosons, Higgs bosons, flavor-changing neutral current in the model 3−3−3−1 and calculate the branch ratio of the decay process mu - ey, u - 3e in the model.
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Summary of physics doctoral thesis: Some new physical effects in the 3−2−3−1 and 3−3−3−1 models MINISTRY OF EDUCATION VIETNAM ACADEMY AND TRAINING OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY - - - - - - - - *** - - - - - - - - NGUYEN THI NHUAN SOME NEW PHYSICAL EFFECTS IN THE 3 − 2 − 3 − 1 AND 3 − 3 − 3 − 1 MODELS Major: Theoretical and Mathematical Physics Code: 9 44 01 03 SUMMARY OF PHYSICS DOCTORAL THESIS Hanoi - 2019 INTRODUCTION 1. The urgency of the thesis The standard model (SM )of particle physics is based on two principal the- ories including electroweak theory with the SU (2)L × U (1)Y gauge symmetry and QCD theory with SU (3)c gauge symmetry. The SM describes elementary particles which create matter and their interactions which make the entire universe. In the SM, three interactions of particles are described successfully: strong interactions, electromagnetic interactions and weak interactions. Many predictions of the SM such as: the existence of W ± , Z boson, quark c, t, neutral currents ... have been verified with high fidelity by experiments. W, Z found in 1981 with the masses measured as the model proposed. There are many ways to expand SM such as introducing the spectral particles, extend gauge group,etc. Therefore, we would suggest two expansion models: the 3 − 2 − 3 − 1 and the 3−3−3−1 models. The 3−2−3−1 model is based on the gauge group SU (3)C ⊗ SU (2)L ⊗ SU (3)R ⊗ U (1)X . The 3 − 2 − 3 − 1 model solves the neu- trino masses problem, provides naturally candidate for dark matter, indicates the existence of FCNC at the approximate tree caused by the gauge bosons and Higgs, explains why are there three fermion generations. The 3 − 3 − 3 − 1 model is based on the gauge group SU (3)C ⊗ SU (3)L ⊗ SU (3)R ⊗ U (1)X . It unifies both the left-right and 3-3-1 symmetries, so it inherits all the good fea- tures of the two models. Therefore, the 3 − 3 − 3 − 1 model solves problems of fermion generation numbers, neutrino masses problems, dark matter problems, parity symmetry in electroweak theory. In particular, the model predicts lep- ton flavor violation of the charged lepton. Especially, on 4/7/2012, a particel was discovered at the Large Hadron Collider (LHC) located at the European Nuclear Research Center using two independent detectors, A Toroidal LHC ApparatuS (ATLAS) and Compact Muon Solenoid (CMS), with a mass mea- sured about 125 − 126 GeV. This particel has characteristics identical to the 1 boson Higgs predicted by SM that has not been found previously. It was the last piece for the picture called Standard Model to be completed. It can be stated that the SM of particle physics is very successful describing interactions in the Universe. However, the SM model can not explain some observed figures in the Universe and recent experimental results. Specifically: Why do neutri- nos have mass? SM does not identify the candidates for dark matter particles. SM does not explain some abnormal decay channels of mesons, higgs ... SM also does not answer the questions: Why are there three fermion generations? Why is asymmetrical between matter and antimatter? Why is mass graded in the fermion spectrum? ... So, an expansion is necessary. For the mentioned reasons, we choose the subject Some new physics effects in the 3 − 2 − 3 − 1 and 3 − 4 − 1 models. 2. The objectives of the thesis • Resolve the neutrino mass problem. Parameterize the parameters in the model 3 − 2 − 3 − 1 to seek for dark matter for each version of the model with q = 0 and q = −1. Research for Z1 and Z10 at LEPII and LHC. • Survey in detail the mass of gauge bosons, Higgs bosons, flavor-changing neutral current in the model 3 − 3 − 3 − 1 and calculate the branch ratio of the decay process mu → eγ, µ → 3e in the model. 3. The main contents of the thesis • Overview of SM, flavor-changing neutral current, neutrino masses and dark matter problems in SM. • Investigate the 3 − 2 − 3 − 1 model with any charge of new leptons, neutrino masses, and identify dark matter candidates in the model and search for dark matter by the method direct search. • Investigate the model 3 − 3 − 3 − 1 with any charge of new leptons, gauge boson masses, Higgs mass, FCNCs, cLFV in decay process µ → eγ, µ → 3e. 2 CHAPTER 1. OVERVIEW 1.1. The Standard Model SM describes strong, electromagnetic and weak interactions based on the gauge symmetry group SU (3)C ⊗SU (2)L ⊗U (1)Y (3−2−1). In particular, the gauge group SU (3)C describes strong interaction, gauge group SU (2)L ⊗U (1)Y describes weak electrical interaction. The electric charge operator: Q = T3 + Y /2. The particles in SM are arranged under the gauge group as follows: Leptons: ! νaL ψaL = ∼ (1, 2, −1), eaL eaR ∼ (1, 1, −2), a = 1, 2, 3. (1.1) Quarks: !   uaL 1 QaL = ∼ 3, 2, , daL 3     4 2 uaR ∼ 3, 1, , daR ∼ 3, 1, − , (1.2) 3 3 where a is the generation index. The SU (3)C ⊗ SU (2)L ⊗ U (1)Y gauge group is broken spontaneously via a single scalar field, ! ! ...