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Author Alves, J.M.; Botella, F.J.; Branco, G.C.; Cornet-Gomez, F.; Nebot, M.
Title Controlled flavour changing neutral couplings in two Higgs Doublet models Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 9 Pages 585 - 18pp
Keywords
Abstract (down) 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.
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;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000409356700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3293
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Author Botella, F.J.; Branco, G.C.; Rebelo, M.N.; Silva-Marcos, J.I.
Title What if the masses of the first two quark families are not generated by the standard model Higgs boson? Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 94 Issue 11 Pages 115031 - 6pp
Keywords
Abstract (down) We point out that in the standard model there is meaningful quark mixing even in the extreme chiral (EC) limit, where only the third generation of quarks acquires mass. This mixing is in general expected to be of order 1 and the fact that |V-13|(2) + |V-23|(2) approximate to 1.6 x 10(-3) implies a novel fine-tuning problem in the SM which we point out for the first time. We propose a possible way of avoiding this fine-tuning by introducing a symmetry S which leads to V-CKM = 1, with only the third generation of quarks acquiring mass. We consider two scenarios for generating the mass of the first two quark generations and full quark mixing based on the assumption that the masses of the first two quark families are not generated by the standard Higgs. One consists of the introduction of a second Higgs doublet which is neutral under S. The second scenario consists of assuming new physics at a high energy scale, contributing to the masses of light quark generations, in an effective field theory approach. This last scenario leads to couplings of the Higgs particle to s (s) over bar and c (c) over tilde which are significantly enhanced with respect to those of the SM. In both schemes, one has scalar-mediated flavor-changing neutral currents which are naturally suppressed. Flavor-violating top decays are predicted in the second scenario at the level Br(t -> hc) >= 5 x 10(-5).
Address [Botella, F. J.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: fbotella@uv.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000391016600004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2931
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Author Botella, F.J.; Branco, G.C.; Nebot, M.; Rebelo, M.N.
Title Two-Higgs leptonic minimal flavour violation Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 037 - 21pp
Keywords Higgs Physics; Beyond Standard Model; Neutrino Physics
Abstract (down) We construct extensions of the Standard Model with two Higgs doublets, where there are flavour changing neutral currents both in the quark and leptonic sectors, with their strength fixed by the fermion mixing matrices V(CKM) and V(PMNS). These models are an extension to the leptonic sector of the class of models previously considered by Branco, Grimus and Lavoura, for the quark sector. We consider both the cases of Dirac and Majorana neutrinos and identify the minimal discrete symmetry required in order to implement the models in a natural way.
Address [Botella, F. J.; Nebot, M.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: fbotella@uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000296917100037 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 830
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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
Abstract (down) 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 Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000873885900002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5395
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Author Botella, F.J.; Cornet-Gomez, F.; Miro, C.; Nebot, M.
Title New physics hints from τ scalar interactions and (g-2)e,μ Type Journal Article
Year 2024 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 51 Issue 2 Pages 025001 - 20pp
Keywords lepton sector; extended scalar sector; new physics signals
Abstract (down) We consider a flavour conserving two Higgs doublet model that consists of a type I (or X) quark sector and a generalized lepton sector where the Yukawa couplings of the charged leptons to the new scalars are not proportional to the lepton masses. The model, previously proposed to solve both muon and electron g – 2 anomalies simultaneously, is also capable to accommodate the ATLAS excess in pp -> S -> tau(+)tau(-) with gluon-gluon fusion production in the invariant mass range [0.2; 0.6] TeV, including all relevant low and high energy constraints. The excess is reproduced taking into account the new contributions from the scalar H, the pseudoscalar A, or both. In particular, detailed numerical analyses favoured the solution with a significant hierarchy among the vevs of the two Higgs doublets, t(beta)similar to 10, and light neutral scalars satisfying m(A) > m(H) with sizable couplings to tau leptons. In this region of the parameter space, the muon g – 2 anomaly receives one and two-loop (Barr Zee) contributions of similar size, while the electron anomaly is explained at two loops. An analogous ATLAS excess in b-associated production and the CMS excess in ditop production are also studied. Further New Physics prospects concerning the anomalous magnetic moment of the tau lepton and the implications of the CDF M-W measurement on the final results are discussed.
Address [Botella, Francisco J.; Miro, Carlos; Nebot, Miguel] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: Francisco.J.Botella@uv.es;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:001132956900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5877
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