Resonant tau leptogenesis with observable lepton number violation

Area of Science:

• Particle Physics
• Cosmology
• Neutrino Physics

Background:

• The Standard Model (SM) of particle physics does not fully explain the observed baryon asymmetry in the Universe.
• Neutrino oscillations indicate non-zero neutrino masses, requiring extensions beyond the SM.
• Leptogenesis is a leading mechanism for generating baryon asymmetry, but often requires very high energy scales.

Purpose of the Study:

• To propose a minimal extension of the Standard Model that can realize resonant leptogenesis at the electroweak scale.
• To explain the observed baryon asymmetry through lepton-to-baryon conversion, specifically involving the tau lepton number.
• To investigate the phenomenological implications and testable predictions of this extended model.

Main Methods:

• Introducing one singlet neutrino per generation into the Standard Model.
• Utilizing a CP-violating Yukawa texture to explain current neutrino data.
• Analyzing the conditions for resonant leptogenesis at the electroweak scale.

Main Results:

• The model successfully explains baryon asymmetry via resonant leptogenesis at accessible energy scales.
• Current neutrino data is consistent with a simple CP-violating Yukawa texture within this model.
• The model predicts the existence of heavy Majorana neutrinos at the electroweak scale.

Conclusions:

• This minimal extension provides a viable mechanism for generating the universe's baryon asymmetry.
• The model's predictions, including heavy neutrinos and lepton-number-violating processes, are within the reach of current and future experimental sensitivities.
• The study highlights testable implications for particle colliders and precision low-energy experiments.