Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations
Abstract Leptoquarks are prime candidates for explaining the intriguing hints for lepton flavour universality violation. In particular, the SU(2) L doublet of scalar leptoquarks S 2 is capable of providing an explanation for the tensions between the measurements and the Standard Model predictions in...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2022-06-01
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| Series: | Journal of High Energy Physics |
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| Online Access: | https://doi.org/10.1007/JHEP06(2022)169 |
| _version_ | 1827985400320229376 |
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| author | Andreas Crivellin Benjamin Fuks Luc Schnell |
| author_facet | Andreas Crivellin Benjamin Fuks Luc Schnell |
| author_sort | Andreas Crivellin |
| collection | DOAJ |
| description | Abstract Leptoquarks are prime candidates for explaining the intriguing hints for lepton flavour universality violation. In particular, the SU(2) L doublet of scalar leptoquarks S 2 is capable of providing an explanation for the tensions between the measurements and the Standard Model predictions in (g − 2) μ , b → sℓ + ℓ − and b → cτν processes, as well as in non-resonant di-electron production. However, in the minimal setup with a single leptoquark generation, a common explanation for all these issues is not possible as this would lead to unacceptably large charged lepton flavour violation. We therefore propose a model with three generations of S 2, each coupling exclusively to a single lepton flavour, i.e. a model extending the Standard Model particle content by an electroquark, a muoquark and a tauquark. We show that after taking into account other constraints, such as those originating from electroweak precision observables and ∆F = 2 processes, it is possible to provide a combined explanation for all these hints of lepton flavour universality violation. Moreover, we find that the presence of the tauquark can generate a dimension-six O 9 U $$ {\mathcal{O}}_9^U $$ operator via off-shell photon penguin diagrams, which, together with the muoquark contribution, further improves the global fit to b → sℓ + ℓ − data. |
| first_indexed | 2024-04-09T23:14:18Z |
| format | Article |
| id | doaj.art-905cfed04a7c4d559b3e5e191a3105a0 |
| institution | Directory Open Access Journal |
| issn | 1029-8479 |
| language | English |
| last_indexed | 2024-04-09T23:14:18Z |
| publishDate | 2022-06-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Journal of High Energy Physics |
| spelling | doaj.art-905cfed04a7c4d559b3e5e191a3105a02023-03-22T10:12:13ZengSpringerOpenJournal of High Energy Physics1029-84792022-06-012022614410.1007/JHEP06(2022)169Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generationsAndreas Crivellin0Benjamin Fuks1Luc Schnell2Physik-Institut, Universität ZürichLaboratoire de Physique Théorique et Hautes Energies (LPTHE), UMR 7589, Sorbonne Université et CNRSMax Planck Institute for PhysicsAbstract Leptoquarks are prime candidates for explaining the intriguing hints for lepton flavour universality violation. In particular, the SU(2) L doublet of scalar leptoquarks S 2 is capable of providing an explanation for the tensions between the measurements and the Standard Model predictions in (g − 2) μ , b → sℓ + ℓ − and b → cτν processes, as well as in non-resonant di-electron production. However, in the minimal setup with a single leptoquark generation, a common explanation for all these issues is not possible as this would lead to unacceptably large charged lepton flavour violation. We therefore propose a model with three generations of S 2, each coupling exclusively to a single lepton flavour, i.e. a model extending the Standard Model particle content by an electroquark, a muoquark and a tauquark. We show that after taking into account other constraints, such as those originating from electroweak precision observables and ∆F = 2 processes, it is possible to provide a combined explanation for all these hints of lepton flavour universality violation. Moreover, we find that the presence of the tauquark can generate a dimension-six O 9 U $$ {\mathcal{O}}_9^U $$ operator via off-shell photon penguin diagrams, which, together with the muoquark contribution, further improves the global fit to b → sℓ + ℓ − data.https://doi.org/10.1007/JHEP06(2022)169Specific BSM PhenomenologyTheories of Flavour |
| spellingShingle | Andreas Crivellin Benjamin Fuks Luc Schnell Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations Journal of High Energy Physics Specific BSM Phenomenology Theories of Flavour |
| title | Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations |
| title_full | Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations |
| title_fullStr | Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations |
| title_full_unstemmed | Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations |
| title_short | Explaining the hints for lepton flavour universality violation with three S 2 leptoquark generations |
| title_sort | explaining the hints for lepton flavour universality violation with three s 2 leptoquark generations |
| topic | Specific BSM Phenomenology Theories of Flavour |
| url | https://doi.org/10.1007/JHEP06(2022)169 |
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