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Author Botella, F.J.; Branco, G.C.; Coutinho, A.M.; Rebelo, M.N.; Silva-Marcos, J.I. url  doi
openurl 
  Title Natural quasi-alignment with two Higgs doublets and RGE stability Type Journal Article
  Year 2015 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 75 Issue 6 Pages 286 - 9pp  
  Keywords  
  Abstract In the context of two Higgs doublet models, we study the conditions required in order to have stable quasi-alignment in flavour space. We show that stability under the renormalisation group equations imposes strong constraints on the flavour structure of the Yukawa couplings associated to each one of the Higgs doublets. In particular, we find a novel solution, where all Yukawa couplings are proportional to the so-called democratic matrix. This solution is rather unique, since it is the only stable solution which is a good starting point for reproducing the observed pattern of quark masses and mixing. We also showthat this stable solution can be obtained by imposing on the Lagrangian a Z(3)xZ(3)' flavour symmetry. Quark masses of the lighter quark generations are generated through the breaking of this discrete symmetry, and, at this stage, scalar-mediated flavour-changing neutralcurrents arise, but they are naturally suppressed by the smallness of the light quark masses. In this way, we relate Higgs alignment to the hierarchy of the quark masses through a discrete family symmetry.  
  Address [Botella, F. J.] 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 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000356888300003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2299  
Permanent link to this record
 
 
Author Botella, F.J.; Branco, G.C.; Nebot, M.; Sanchez, A. url  doi
openurl 
  Title Mixing asymmetries in B meson systems, the D0 like-sign dimuon asymmetry, and generic new physics Type Journal Article
  Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 91 Issue 3 Pages 035013 - 14pp  
  Keywords  
  Abstract The measurement of a large like-sign dimuon asymmetry A(SL)(b) by the D0 experiment at the Tevatron departs noticeably from Standard Model (SM) expectations and it may be interpreted as a hint of physics beyond the Standard Model contributing to Delta B not equal 0 transitions. In this work we analyze how the natural suppression of A(SL)(b) in the SM can be circumvented by new physics. We consider generic Standard Model extensions where the charged current mixing matrix is enlarged with respect to the usual 3 x 3 unitary Cabibbo-Kobayashi-Maskawa matrix, and show how, within this framework, a significant enhancement over Standard Model expectations for Ab SL is easily reachable through enhancements of the semileptonic asymmetries A(SL)(d) and A(SL)(s) of both B-d(0)- (B) over bar (0)(d) and B-s(0)- (B) over bar (0)(s) systems. Despite being insufficient to reproduce the D0 measurement, such deviations from SM expectations may be probed by the LHCb experiment.  
  Address [Botella, F. J.; Sanchez, A.] Univ Valencia, CSIC, Dept Fis Teor, 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 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000349918300005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2137  
Permanent link to this record
 
 
Author Botella, F.J.; Branco, G.C.; Rebelo, M.N. url  doi
openurl 
  Title Invariants and flavour in the general Two Higgs Doublet Model Type Journal Article
  Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 722 Issue 1-3 Pages 76-82  
  Keywords  
  Abstract The flavour structure of the general Two Higgs Doublet Model (2HDM) is analysed and a detailed study of the parameter space is presented, showing that flavour mixing in the 2HDM can be parametrized by various unitary matrices which arise from the misalignment in flavour space between pairs of various Hermitian flavour matrices which can be constructed within the model. This is entirely analogous to the generation of the CKM matrix in the Standard Model (SM). We construct weak basis invariants which can give insight into the physical implications of any flavour model, written in an arbitrary weak basis (WB) in the context of 2HDM. We apply this technique to two special cases, models with MFV and models with NNI structures. In both cases non-trivial CP-odd WB invariants arise in a mass power order much smaller than what one encounters in the SM, which can have important implications for baryogenesis in the framework of the general 2HDM.  
  Address Univ Valencia CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: fbotella@uv.es;  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000318745300008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1451  
Permanent link to this record
 
 
Author Botella, F.J.; Branco, G.C.; Nebot, M. url  doi
openurl 
  Title The hunt for New Physics in the Flavour Sector with up vector-like quarks Type Journal Article
  Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 12 Issue 12 Pages 040 - 34pp  
  Keywords Beyond Standard Model; Rare Decays; CP violation  
  Abstract We analyse the possible presence of New Physics (NP) in the Flavour Sector and evaluate its potential for solving the tension between the experimental values of A(J/Psi KS) and Br(B+ -> tau(+)v(tau)) with respect to the Standard Model (SM) expectations. Updated model independent analyses, where NP contributions are allowed in B-d(0) – (B) over bar (0)(d) and B-s(0) – (B) over bar (0)(s) transitions, suggest the need of New Physics in the bd sector. A detailed analysis of recent Flavour data is then presented in the framework of a simple extension of the SM, where a Q = 2/3 vector-like isosinglet quark is added to the spectrum of the SM. Special emphasis is given to the implications of this model for correlations among various measurable quantities. We include constraints from all the relevant quark flavour sectors and give precise predictions for selected rare processes. We find important deviations from the SM in observables in the bd sector like the semileptonic asymmetry A(SL)(d), B-d(0) -> mu(+)mu(-) and A(SL)(s) – A(SL)(d). Other potential places where NP can show up include A(J/Psi Phi), gamma, K-L(0) -> pi(0)v (v) over bar, t -> Zq and D-0 -> mu(+)mu(-) among others. The experimental data favours in this model the existence of an up vector-like quark with a mass below 600(1000) GeV at 1(2) sigma.  
  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:000313123800040 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1344  
Permanent link to this record
 
 
Author Botella, F.J.; Branco, G.C.; Nebot, M.; Rebelo, M.N. url  doi
openurl 
  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 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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