Relaxing cosmological neutrino mass bounds with unstable neutrinos
Abstract At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model (ΛCDM), the Planck collaboration reports ∑m v < 0.12 eV at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2020-12-01
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| Series: | Journal of High Energy Physics |
| Subjects: | |
| Online Access: | https://doi.org/10.1007/JHEP12(2020)119 |
| _version_ | 1818589581453295616 |
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| author | Miguel Escudero Jacobo Lopez-Pavon Nuria Rius Stefan Sandner |
| author_facet | Miguel Escudero Jacobo Lopez-Pavon Nuria Rius Stefan Sandner |
| author_sort | Miguel Escudero |
| collection | DOAJ |
| description | Abstract At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model (ΛCDM), the Planck collaboration reports ∑m v < 0.12 eV at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable neutrinos, with lifetimes shorter than the age of the universe τ ν ≲ t U , represent a particle physics avenue to relax this constraint. Motivated by this fact, we present a taxonomy of neutrino decay modes, categorizing them in terms of particle content and final decay products. Taking into account the relevant phenomenological bounds, our analysis shows that 2-body decaying neutrinos into BSM particles are a promising option to relax cosmological neutrino mass bounds. We then build a simple extension of the type I seesaw scenario by adding one sterile state ν 4 and a Goldstone boson ϕ, in which ν i → ν 4 ϕ decays can loosen the neutrino mass bounds up to ∑m v ∼ 1 eV, without spoiling the light neutrino mass generation mechanism. Remarkably, this is possible for a large range of the right-handed neutrino masses, from the electroweak up to the GUT scale. We successfully implement this idea in the context of minimal neutrino mass models based on a U(1) μ−τ flavor symmetry, which are otherwise in tension with the current bound on ∑m v . |
| first_indexed | 2024-12-16T09:42:55Z |
| format | Article |
| id | doaj.art-d48e6b90fdb34bae804d19e0750a8b31 |
| institution | Directory Open Access Journal |
| issn | 1029-8479 |
| language | English |
| last_indexed | 2024-12-16T09:42:55Z |
| publishDate | 2020-12-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Journal of High Energy Physics |
| spelling | doaj.art-d48e6b90fdb34bae804d19e0750a8b312022-12-21T22:36:13ZengSpringerOpenJournal of High Energy Physics1029-84792020-12-0120201214410.1007/JHEP12(2020)119Relaxing cosmological neutrino mass bounds with unstable neutrinosMiguel Escudero0Jacobo Lopez-Pavon1Nuria Rius2Stefan Sandner3Theoretical Particle Physics and Cosmology Group, Department of Physics, King’s College LondonDepartamento de Física Teórica and IFIC, Universidad de Valencia-CSICDepartamento de Física Teórica and IFIC, Universidad de Valencia-CSICDepartamento de Física Teórica and IFIC, Universidad de Valencia-CSICAbstract At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model (ΛCDM), the Planck collaboration reports ∑m v < 0.12 eV at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable neutrinos, with lifetimes shorter than the age of the universe τ ν ≲ t U , represent a particle physics avenue to relax this constraint. Motivated by this fact, we present a taxonomy of neutrino decay modes, categorizing them in terms of particle content and final decay products. Taking into account the relevant phenomenological bounds, our analysis shows that 2-body decaying neutrinos into BSM particles are a promising option to relax cosmological neutrino mass bounds. We then build a simple extension of the type I seesaw scenario by adding one sterile state ν 4 and a Goldstone boson ϕ, in which ν i → ν 4 ϕ decays can loosen the neutrino mass bounds up to ∑m v ∼ 1 eV, without spoiling the light neutrino mass generation mechanism. Remarkably, this is possible for a large range of the right-handed neutrino masses, from the electroweak up to the GUT scale. We successfully implement this idea in the context of minimal neutrino mass models based on a U(1) μ−τ flavor symmetry, which are otherwise in tension with the current bound on ∑m v .https://doi.org/10.1007/JHEP12(2020)119Beyond Standard ModelCosmology of Theories beyond the SMNeutrino Physics |
| spellingShingle | Miguel Escudero Jacobo Lopez-Pavon Nuria Rius Stefan Sandner Relaxing cosmological neutrino mass bounds with unstable neutrinos Journal of High Energy Physics Beyond Standard Model Cosmology of Theories beyond the SM Neutrino Physics |
| title | Relaxing cosmological neutrino mass bounds with unstable neutrinos |
| title_full | Relaxing cosmological neutrino mass bounds with unstable neutrinos |
| title_fullStr | Relaxing cosmological neutrino mass bounds with unstable neutrinos |
| title_full_unstemmed | Relaxing cosmological neutrino mass bounds with unstable neutrinos |
| title_short | Relaxing cosmological neutrino mass bounds with unstable neutrinos |
| title_sort | relaxing cosmological neutrino mass bounds with unstable neutrinos |
| topic | Beyond Standard Model Cosmology of Theories beyond the SM Neutrino Physics |
| url | https://doi.org/10.1007/JHEP12(2020)119 |
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