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Author |
Alves, J.M.; Botella, F.J.; Branco, G.C.; Nebot, M. |
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Title |
Extending trinity to the scalar sector through discrete flavoured symmetries |
Type |
Journal Article |
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Year |
2020 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
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Volume |
80 |
Issue |
8 |
Pages  |
710 - 14pp |
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Keywords |
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Abstract |
We conjecture the existence of a relation between elementary scalars and fermions, making it plausible the existence of three Higgs doublets. We introduce a Trinity Principle (TP) which, given the fact that there are no massless quarks, requires the existence of a minimum of three Higgs doublets. The TP states that each row of the mass matrix of a quark of a given charge should receive the contribution from one and only one scalar doublet and furthermore a given scalar doublet should contribute to one and only one row of the mass matrix of a quark of a given charge. This principle is analogous to the Natural Flavour Conservation (NFC) of Glashow and Weinberg with the key distinction that NFC required the introduction of a flavour blind symmetry, while the TP requires a flavoured symmetry, to be implemented in a natural way. We provide two examples which satisfy the Trinity Principle based on Z(3) and Z(2) x Z(2)' flavoured symmetries, and show that they are the minimal multi-Higgs extensions of the Standard Model where CP can be imposed as a symmetry of the full Lagrangian and broken by the vacuum, without requiring soft-breaking terms. We show that the vacuum phases are sufficient to generate a complex CKM matrix, in agreement with experiment. The above mentioned flavoured symmetries lead to a strong reduction in the number of parameters in the Yukawa interactions, enabling a control of the Scalar Flavour Changing Neutral Couplings (SFCNC). We analyse some of the other physical implications of the two models, including an estimate of the enhancement of the Baryon Asymmetry of the Universe provided by the new sources of CP violation, and a discussion of the strength of their tree-level SFCNC. |
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Address |
[Alves, Joao M.; Branco, Gustavo C.; Nebot, Miguel] Univ Lisboa UL, Inst Super Tecn IST, Dept Fis, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: j.magalhaes.alves@tecnico.ulisboa.pt; |
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Publisher |
Springer |
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Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
1434-6044 |
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Conference |
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Notes |
WOS:000561119300002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4503 |
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Author |
Alves, J.M.; Botella, F.J.; Branco, G.C.; Cornet-Gomez, F.; Nebot, M.; Silva, J.P. |
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Title |
Symmetry constrained two Higgs doublet models |
Type |
Journal Article |
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Year |
2018 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
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Volume |
78 |
Issue |
8 |
Pages |
630 - 17pp |
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Keywords |
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Abstract |
We study two-Higgs-doublet models (2HDM) where Abelian symmetries have been introduced, leading to a drastic reduction in the number of free parameters in the 2HDM. Our analysis is inspired in BGL models, where, as the result of a symmetry of the Lagrangian, there are tree-level scalar mediated Flavour-Changing-Neutral-Currents, with the flavour structure depending only on the CKM matrix. A systematic analysis is done on the various possible schemes, which are classified in different classes, depending on the way the extra symmetries constrain the matrices of couplings defining the flavour structure of the scalar mediated neutral currents. All the resulting flavour textures of the Yukawa couplings are stable under renormalisation since they result from symmetries imposed at the Lagrangian level. We also present a brief phenomenological analysis of the most salient features of each class of symmetry constrained 2HDM. |
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Address |
[Alves, Joao M.; Branco, Gustavo C.; Nebot, Miguel; Silva, Joao P.] Univ Lisboa UL, Dept Fis, Av Rovisco Pais, P-1049001 Lisbon, Portugal, Email: j.magalhaes.alves@tecnico.ulisboa.pt; |
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Publisher |
Springer |
Place of Publication |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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ISSN |
1434-6044 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000441261300003 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3690 |
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Author |
Peris, J.B.; Davis, P.; Cuevas, J.M.; Nebot, M.; Sanjuan, R. |
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Title |
Distribution of Fitness Effects Caused by Single-Nucleotide Substitutions in Bacteriophage f1 |
Type |
Journal Article |
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Year |
2010 |
Publication |
Genetics |
Abbreviated Journal |
Genetics |
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Volume |
185 |
Issue |
2 |
Pages |
603-U308 |
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Keywords |
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Abstract |
Empirical knowledge of the fitness effects of mutations is important for understanding many evolutionary processes, yet this knowledge is often hampered by several sources of measurement error and bias. Most of these problems can be solved using site-directed mutagenesis to engineer single mutations, an approach particularly suited for viruses due to their small genomes. Here, we used this technique to measure the fitness effect of 100 single-nucleotide substitutions in the bacteriophage f1, a filamentous single-strand DNA virus. We found that approximately one-fifth of all mutations are lethal. Viable ones reduced fitness by 11% on average and were accurately described by a log-normal distribution. More than 90% of synonymous substitutions were selectively neutral, while those affecting intergenic regions reduced fitness by 14% on average. Mutations leading to amino acid substitutions had an overall mean deleterious effect of 37%, which increased to 45% for those changing the amino acid polarity. Interestingly, mutations affecting early steps of the infection cycle tended to be more deleterious than those affecting late steps. Finally, we observed at least two beneficial mutations. Our results confirm that high mutational sensitivity is a general property of viruses with small genomes, including RNA and single-strand DNA viruses infecting animals, plants, and bacteria. |
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Address |
[Peris, Joan B.; Davis, Paulina; Cuevas, Jose M.; Sanjuan, Rafael] Univ Valencia, Inst Cavanilles Biodiversitat & Biol Evolut, Valencia 46980, Spain, Email: rafael.sanjuan@uv.es |
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Publisher |
Genetics Soc Am |
Place of Publication |
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Language |
English |
Summary Language |
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Abbreviated Series Title |
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Edition |
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ISSN |
0016-6731 |
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Notes |
ISI:000281905200017 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
no |
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Call Number |
IFIC @ elepoucu @ |
Serial |
383 |
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Author |
Alves, J.M.; Botella, F.J.; Branco, G.C.; Cornet-Gomez, F.; Nebot, M. |
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Title |
Controlled flavour changing neutral couplings in two Higgs Doublet models |
Type |
Journal Article |
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Year |
2017 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
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Volume |
77 |
Issue |
9 |
Pages |
585 - 18pp |
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Keywords |
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Abstract |
We propose a class of two Higgs doublet models where there are flavour changing neutral currents (FCNC) at tree level, but under control due to the introduction of a discrete symmetry in the full Lagrangian. It is shown that in this class of models, one can have simultaneously FCNC in the up and down sectors, in contrast to the situation encountered in the renormalisable and minimal flavour violating 2HDM models put forward by Branco et al. (Phys Lett B 380: 119, 1996). The intensity of FCNC is analysed and it is shown that in this class of models one can respect all the strong constraints from experiment without unnatural fine-tuning. It is pointed out that the additional sources of flavour and CP violation are such that they can enhance significantly the generation of the Bbaryon asymmetry of the Universe, with respect to the standard model. |
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Address |
[Alves, Joao M.; Branco, Gustavo C.; Nebot, Miguel] UL, IST, Dept Fis, Ave Rovisco Pais, P-1049001 Lisbon, Portugal, Email: j.magalhaes.alves@tecnico.ulisboa.pt; |
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Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6044 |
ISBN |
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Area |
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Conference |
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Notes |
WOS:000409356700001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3293 |
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Author |
Herrero-Garcia, J.; Nebot, M.; Rius, N.; Santamaria, A. |
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Title |
The Zee-Babu model revisited in the light of new data |
Type |
Journal Article |
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Year |
2014 |
Publication |
Nuclear Physics B |
Abbreviated Journal |
Nucl. Phys. B |
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Volume |
885 |
Issue |
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Pages |
542-570 |
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Keywords |
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Abstract |
We update previous analyses of the Zee-Babu model in the light of new data, e.g., the mixing angle On, the rare decay μ-> e gamma and the LHC results. We also analyze the possibility of accommodating the deviations in Gamma (H -> gamma gamma) hinted by the LHC experiments, and the stability of the scalar potential. We find that neutrino oscillation data and low energy constraints are still compatible with masses of the extra charged scalars accessible to LHC. Moreover, if any of them is discovered, the model can be falsified by combining the information on the singly and doubly charged scalar decay modes with neutrino data. Conversely, if the neutrino spectrum is found to be inverted and the CP phase delta is quite different from pi, the masses of the charged scalars will be well outside the LHC reach. |
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Address |
[Herrero-Garcia, Juan; Rius, Nuria; Santamaria, Arcadi] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, Valencia, Spain |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0550-3213 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000339598300025 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1858 |
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