A full picture of large lepton number asymmetries of the Universe
| Autor: | Gabriela Barenboim, Wan-Il Park |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Physics
Particle physics 010308 nuclear & particles physics Entropy production media_common.quotation_subject High Energy Physics::Phenomenology Electroweak interaction Astronomy and Astrophysics 01 natural sciences Lepton number Asymmetry Universe 0103 physical sciences High Energy Physics::Experiment Baryon number 010303 astronomy & astrophysics Entropy (arrow of time) Vacuum expectation value media_common |
| Zdroj: | Journal of Cosmology and Astroparticle Physics |
| ISSN: | 1475-7516 0044-0027 1126-6708 |
| Popis: | A large lepton number asymmetry of (0.1−1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 03. Therefore a mild entropy release causing (10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = (10−2-102) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m (10) TeV and 0 (1014) GeV, respectively. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink