Dynamical generation of the baryon asymmetry from a scale hierarchy

Journal Article · 26 September 2024 · Physical Review. D.

DOI: https://doi.org/10.1103/PhysRevD.110.055038 · OSTI ID:2448118

Chang, Jae Hyeok ; Jeong, Kwang Sik; Lee, Chang Hyeon ; Shin, Chang Sub

We propose a novel baryogenesis scenario where the baryon asymmetry originates directly from a hierarchy between two fundamental mass scales: the electroweak scale $v$ and the Planck scale $M_P$ , in the form of $Y_B\sim \sqrt{\frac{v}{M_P}}.$ This relation straightforwardly gives the observed baryon yield today $Y_B$ , which can be a hint for underlying fundamental physics. We provide an example of baryogenesis models that yield this relation. Our model is based on the neutrino-portal Affleck-Dine mechanism, which generates the asymmetry of the Affleck-Dine sector during the radiation-dominated era and subsequently transfers it to the baryon number before the electroweak phase transition. The observed baryon asymmetry is then a natural outcome of this scenario. The model is testable as it predicts the existence of a Majoron with a keV mass and an electroweak scale decay constant. The impact of the relic Majoron on the effective number of neutrinos ( $\mathrm{\Delta }{N}_{\mathrm{eff}}$ ) can be measured through near-future cosmic microwave background observations. Published by the American Physical Society 2024

• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 2448118
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 5 Vol. 110; ISSN PRVDAQ; ISSN 2470-0010
• Publisher: American Physical SocietyCopyright Statement
• Country of Publication: United States
• Language: English