In modular-invariant models of flavour, hierarchical fermion mass matrices may arise solely due to the proximity of the modulus tau to a point of residual symmetry. This mechanism does not require flavon fields, and modular weights are not analogous to Froggatt-Nielsen charges. Instead, we show that hierarchies depend on the decomposition of field representations under the residual symmetry group. We systematically go through the possible fermion field representation choices which may yield hierarchical structures in the vicinity of symmetric points, for the four smallest finite modular groups, isomorphic to S-3, A(4), S-4, and A(5), as well as for their double covers. We find a restricted set of pairs of representations for which the discussed mechanism may produce viable fermion (charged-lepton and quark) mass hierarchies. We present two lepton flavour models in which the charged-lepton mass hierarchies are naturally obtained, while lepton mixing is somewhat fine-tuned. After formulating the conditions for obtaining a viable lepton mixing matrix in the symmetric limit, we construct a model in which both the charged-lepton and neutrino sectors are free from fine-tuning.

Fermion mass hierarchies, large lepton mixing and residual modular symmetries / Novichkov, P. P.; Penedo, J. T.; Petcov, S. T.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2021:4(2021), pp. 1-49. [10.1007/jhep04(2021)206]

Fermion mass hierarchies, large lepton mixing and residual modular symmetries

Penedo, J. T.;Petcov, S. T.
2021-01-01

Abstract

In modular-invariant models of flavour, hierarchical fermion mass matrices may arise solely due to the proximity of the modulus tau to a point of residual symmetry. This mechanism does not require flavon fields, and modular weights are not analogous to Froggatt-Nielsen charges. Instead, we show that hierarchies depend on the decomposition of field representations under the residual symmetry group. We systematically go through the possible fermion field representation choices which may yield hierarchical structures in the vicinity of symmetric points, for the four smallest finite modular groups, isomorphic to S-3, A(4), S-4, and A(5), as well as for their double covers. We find a restricted set of pairs of representations for which the discussed mechanism may produce viable fermion (charged-lepton and quark) mass hierarchies. We present two lepton flavour models in which the charged-lepton mass hierarchies are naturally obtained, while lepton mixing is somewhat fine-tuned. After formulating the conditions for obtaining a viable lepton mixing matrix in the symmetric limit, we construct a model in which both the charged-lepton and neutrino sectors are free from fine-tuning.
2021
2021
4
1
49
206
https://doi.org/10.1007/JHEP04(2021)206
https://arxiv.org/abs/2102.07488
Novichkov, P. P.; Penedo, J. T.; Petcov, S. T.
File in questo prodotto:
File Dimensione Formato  
JHEP04(2021)206 (1).pdf

accesso aperto

Tipologia: Versione Editoriale (PDF)
Licenza: Creative commons
Dimensione 1.7 MB
Formato Adobe PDF
1.7 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11767/142074
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 69
  • ???jsp.display-item.citation.isi??? 74
social impact