| Records |
| Author |
Nebot, M.; Botella, F.J.; Branco, G.C. |
| Title |
Vacuum induced CP violation generating a complex CKM matrix with controlled scalar FCNC |
Type |
Journal Article |
| Year |
2019 |
Publication |
European Physical Journal C |
Abbreviated Journal  |
Eur. Phys. J. C |
| Volume |
79 |
Issue |
8 |
Pages |
711 - 23pp |
| Keywords |
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| Abstract |
We propose. a viable minimal model with spontaneous CP violation in the framework of a two Higgs doublet model. The model is based on a generalised Branco-Grimus-Lavoura model with a flavoured Z(2) symmetry, under which two of the quark families are even and the third one is odd. The lagrangian respects CP invariance, but the vacuum has a CP violating phase, which is able to generate a complex CKM matrix, with the rephasing invariant strength of CP violation compatible with experiment. The question of scalar mediated flavour changing neutral couplings is carefully studied. In particular we point out a deep connection between the generation of a complex CKM matrix from a vacuum phase and the appearance of scalar FCNC. The scalar sector is presented in detail, showing that the new scalars are necessarily lighter than 1 TeV. A complete analysis of the model including the most relevant constraints is performed, showing that it is viable and that it has definite implications for the observation of New Physics signals in, for example, flavour changing Higgs decays or the discovery of the new scalars at the LHC. We give special emphasis to processes like t -> hc, hu, as well as h -> bs, bd, which are relevant for the LHC and the ILC. |
| Address |
[Nebot, Miguel; Branco, Gustavo C.] UL, Dept Fis, Inst Super Tecn, Av Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: miguel.r.nebot.gomez@tecnico.ulisboa.pt; |
| 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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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000483225300003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4130 |
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| Author |
Alves, J.M.; Botella, F.J.; Branco, G.C.; Nebot, M. |
| Title |
Extending trinity to the scalar sector through discrete flavoured symmetries |
Type |
Journal Article |
| Year |
2020 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
80 |
Issue |
8 |
Pages |
710 - 14pp |
| 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. |
| 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; |
| 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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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000561119300002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| 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. |
| Title |
The framework for a common origin of delta(CKM) and delta S-PMN |
Type |
Journal Article |
| Year |
2021 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
81 |
Issue |
8 |
Pages |
727 - 11pp |
| Keywords |
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| Abstract |
We analyse a possible connection between CP violations in the quark and lepton sectors, parametrised by the CKM and PMNS phases. If one assumes that CP breaking arises from complexYukawa couplings, both in the quark and lepton sectors, the above connection is not possible in general, sinceYukawa couplings in the two sectors have independent flavour structures. We show that both the CKM and PMNS phases can instead be generated by a vacuum phase in a class of two Higgs doublet models, and in this case a connection may be established. This scenario requires the presence of scalar FCNC at tree level, both in the quark and lepton sectors. The appearance of these FCNC is an obstacle and a blessing. An obstacle since one has to analyse which models are able to conform to the strict experimental limits on FCNC, both in the quark and lepton sectors. A blessing, because this class of models is falsifiable since FCNC arise at a level which can be probed experimentally in the near future, specially in the processes h up arrow e(+/-) t +/- and t -> hc. The connection between CP violations in CKM and PMNS is explicitely illustrated in models with Minimal Flavour Violation. |
| Address |
[Alves, Joao M.; Branco, Gustavo C.] Univ Lisbon, Inst Super Tecn, CFTP, Av Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: j.magalhaes.alves@tecnico.ulisboa.pt; |
| 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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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000685140600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4938 |
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| Author |
Botella, F.J.; Cornet-Gomez, F.; Miro, C.; Nebot, M. |
| Title |
Muon and electron g-2 anomalies in a flavor conserving 2HDM with an oblique view on the CDF M-W value |
Type |
Journal Article |
| Year |
2022 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
82 |
Issue |
10 |
Pages |
915 - 25pp |
| Keywords |
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| Abstract |
We consider a type I or type X two Higgs doublets model with a modified lepton sector. The generalized lepton sector is also flavor conserving but with the new Yukawa couplings completely decoupled from lepton mass proportionality. The model is one loop stable under renormalization group evolution and it allows to reproduce the g – 2 muon anomaly together with the different scenarios one can consider for the electron g – 2 anomaly, related to the Cesium and/or to the Rubidium recoilmeasurements of the fine structure constant. Thorough parameter space analyses are performed to constrain all the model parameters in the different scenarios, either including or not including the recent CDF measurement of the W boson mass. For light new scalars with masses in the 0.2-1.0 TeV range, the muon anomaly receives dominant one loop contributions; it is for heavy new scalars with masses above 1.2 TeV that two loop Barr-Zee diagrams are needed. The electron g-2 anomaly, if any, must always be obtained with the two loop contributions. The final allowed regions are quite sensitive to the assumptions about perturbativity of Yukawa couplings, which influence unexpected observables like the allowed scalar mass ranges. On that respect, intermediate scalar masses, highly constrained by direct LHC searches, are allowed provided that the new lepton Yukawa couplings are fully scrutinized, including values up to 250 GeV. In the framework of a complete model, fully numerically analysed, we show the implications of the recent M-W measurement. |
| Address |
[Botella, Francisco J.; Cornet-Gomez, Fernando; Miro, Carlos; Nebot, Miguel] Univ Valencia, Dept Fis Teor, CSIC, Burjassot 46100, Spain, Email: Francisco.J.Botella@uv.es; |
| 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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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:000873885900002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5395 |
| Permanent link to this record |
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| Author |
Alves, J.M.; Botella, F.J.; Miro, C.; Nebot, M. |
| Title |
Spontaneous CP violation and μ-τ symmetry intwo-Higgs-doublet models with flavour conservation |
Type |
Journal Article |
| Year |
2023 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
83 |
Issue |
10 |
Pages |
940 - 12pp |
| Keywords |
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| Abstract |
In multi-Higgs-doublet models, requiring simultaneously that (i) CP violation only arises spontaneously, (ii)tree level scalar flavour changing couplings are absent and (iii) the fermion mixing matrix is CP violating, can only be achieved in a very specific manner. A general approach with new clarifying insights on the question is presented. Considering the quark sector, that peculiar possibility is not viable on phenomenological grounds. We show that, considering the lepton sector, it is highly interesting and leads to viable models with mu-tau symmetric PMNS matrices. Phenomenological implications of the models, both for Dirac and Majorana (in a type I seesaw scenario) neutrinos, are analysed. |
| Address |
[Miro, Carlos] Univ Valencia, Dept Fis Teor, CSIC, Valencia 46100, Spain, Email: j.magalhaes.alves@tecnico.ulisboa.pt; |
| 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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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
WOS:001087967500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
5759 |
| Permanent link to this record |
