A viable model with violation.

Area of Science:

• Particle Physics
• Beyond Standard Model Physics
• High Energy Physics

Background:

• The Standard Model (SM) of particle physics successfully describes fundamental particles and forces but does not account for neutrino masses.
• Extensions to the SM are necessary to incorporate phenomena like neutrino oscillations and masses.

Purpose of the Study:

• To propose an extension of the Standard Model gauge group by U(1)X.
• To introduce new scalar particles (a doublet and a singlet) with lepton flavor violating couplings.
• To explore the phenomenological consequences of this extended model, including potential signatures at particle colliders and implications for neutrino physics.

Main Methods:

• Extending the Standard Model gauge group with an additional U(1)X symmetry.
• Introducing new scalar fields charged under U(1)X with specific couplings.
• Analyzing constraints from lepton flavor violating transitions and potential collider signatures.
• Investigating the role of sterile neutrinos in generating neutrino masses and mixing.

Main Results:

• The proposed model allows for lepton flavor violating processes mediated by new gauge interactions, evading stringent bounds from existing transitions.
• Specific scenarios with a U(1)X boson (Z') in the GeV mass range are accessible at Belle-II.
• A long-lived Z' boson with a specific mass can be detected through dedicated searches.
• The model provides a mechanism for generating neutrino masses and mixing angles through the inclusion of sterile neutrinos.

Conclusions:

• The proposed extension of the Standard Model offers a viable framework for new physics phenomena, including lepton flavor violation and neutrino masses.
• The model predicts observable signatures at current and future collider experiments, such as Belle-II.
• Further investigation into the parameter space and experimental searches can test this new physics scenario.