1.
|
Leptonic Invariants, Neutrino Mass-Ordering and the Octant of $\theta_{23}$
/ Branco, G.C. (Lisbon, IST ; CERN ; Lisbon, CFTP) ; Rebelo, M.N. (Lisbon, IST ; CERN ; Lisbon, CFTP) ; Silva-Marcos, J.I. (Lisbon, IST ; Lisbon, CFTP)
We point out that leptonic weak-basis invariants are an important tool for the study of the properties of lepton flavour models. In particular, we show that appropriately chosen invariants can give a clear indication of whether a particular lepton flavour model favours normal or inverted hierarchy for neutrino masses and what is the octant of $\theta_{23}$. [...]
arXiv:1705.07758; CERN-TH-2017-075.-
2017-11-06 - 10 p.
- Published in : JHEP 11 (2017) 001
Article from SCOAP3: scoap3-fulltext - PDF; scoap - PDF; Fulltext: PDF;
|
|
2.
|
Spontaneous symmetry breaking in three-Higgs-doublet $S_3$-symmetric models
/ Emmanuel-Costa, D. (Lisbon, CFTP ; Lisbon, IST) ; Ogreid, O.M. (U. Bergen (main)) ; Osland, P. (Bergen U.) ; Rebelo, M.N. (Lisbon, CFTP ; Lisbon, IST ; CERN)
The talk summarises work done by the authors consisting of a detailed study of the possible vacua in models with three Higgs doublets with $S_3$ symmetry and without explicit CP violation. Different vacua require special regions of the parameter space which were analysed in our work. [...]
CERN-TH-2017-070; arXiv:1703.08457.-
2017-07-27 - 11 p.
- Published in : J. Phys.: Conf. Ser. 873 (2017) 012007
Fulltext from Publisher: PDF; Preprint: PDF;
In : 5th Symposium on Prospects in the Physics of Discrete Symmetries, Warsaw, Poland, 28 Nov - 3 Dec 2016, pp.012007
|
|
3.
|
Natural Quasi-Alignment with two Higgs Doublets and RGE Stability
/ Botella, F.J. (Valencia U. ; Valencia U., IFIC) ; Branco, G.C. (Lisbon, CFTP ; Lisbon, IST ; CERN) ; Coutinho, António M. (Lisbon, CFTP) ; Rebelo, M.N. (Lisbon, CFTP) ; Silva-Marcos, J.I. (Lisbon, CFTP)
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 RGE imposes strong constraints on the flavour structure of the Yukawa couplings associated to each one of the Higgs doublets. [...]
arXiv:1501.07435; CERN-PH-TH-2015-012; CERN-PH-TH-2015-012.-
Geneva : CERN, 2015-06-26 - 16 p.
- Published in : Eur. Phys. J. C 75 (2015) 286
Article from SCOAP3: PDF; Fulltext: PDF; Springer Open Access article: PDF; External link: Preprint
|
|
4.
|
3HDM with ∆(27) symmetry and its phenomenological consequences
/ Kalinowski, J. (Warsaw U. ; CERN) ; Kotlarski, W. (Dresden, Tech. U. ; NCBJ, Warsaw) ; Rebelo, M.N. (Lisbon, CFTP) ; de Medeiros Varzielas, I. (Lisbon, CFTP)
We perform a comprehensive analysis of a version of the 3-Higgs doublet model whose scalar potential is invariant under a global $\Delta(27)$ discrete symmetry and where the three scalar doublets are chosen to transform as a triplet under this discrete group. For each of the known tree-level minima we study the mass spectra and use the oblique parameters $STU$ as well as perturbative unitarity to constrain the parameter space of the model. [...]
arXiv:2112.12699; CERN-TH-2021-182.-
2023-02-24 - 27 p.
- Published in : JHEP 2302 (2023) 231
Fulltext: document - PDF; 2112.12699 - PDF;
|
|
5.
|
Type-I Seesaw with eV-Scale Neutrinos
/ Branco, G.C. (Lisbon, CFTP) ; Penedo, J.T. (Lisbon, CFTP) ; Pereira, Pedro M.F. (Lisbon, CFTP) ; Rebelo, M.N. (Lisbon, CFTP ; CERN) ; Silva-Marcos, J.I. (Lisbon, CFTP)
We consider seesaw type-I models including at least one (mostly-)sterile neutrino with mass at the eV scale. Three distinct situations are found, where the presence of light extra neutrinos is naturally justified by an approximately conserved lepton number symmetry. [...]
arXiv:1912.05875.-
2020-07-23 - 43 p.
- Published in : JHEP 2007 (2020) 164
Article from SCOAP3: PDF; Fulltext: PDF;
|
|
6.
|
What if the Masses of the First Two Quark Families are not Generated by the Standard Higgs?
/ Botella, F.J. (Valencia U. ; Valencia U., IFIC ; CERN) ; Branco, G.C. (Lisbon, CFTP ; Lisbon, IST ; CERN) ; Rebelo, M.N. (Lisbon, CFTP ; Lisbon, IST ; CERN) ; Silva-Marcos, J.I. (Lisbon, CFTP ; Lisbon, IST)
We point out that, in the context of the SM, $|V^2_{13}| + | V^2_{23}|$ is expected to be large, of order one. The fact that $|V^2_{13}| + |V^2_{23}| \approx 1.6 \times 10^{-3}$ motivates the introduction of a symmetry S which leads to $V_{CKM} ={1\>\!\!\!\mathrm{I}} $, with only the third generation of quarks acquiring mass. [...]
arXiv:1602.08011; CERN-TH-2016-039; CERN-TH-2016-039.-
Geneva : CERN, 2016-12-29 - 6 p.
- Published in : Phys. Rev. D 94 (2016) 115031
Fulltext: 10.1103_PhysRevD.94.115031 - PDF; arXiv:1602.08011 - PDF; External link: Preprint
|
|
7.
|
Spontaneous symmetry breaking in the $S_3$-symmetric scalar sector
/ Emmanuel-Costa, D. (Lisbon, CFTP) ; Ogreid, O.M. (Bergen Coll. Higher Educ.) ; Osland, P. (Bergen U.) ; Rebelo, M.N. (Lisbon, CFTP ; CERN)
We present a detailed study of the vacua of the $S_3$-symmetric three-Higgs-doublet potential, specifying the region of parameters where these minimisation solutions occur. We work with a CP conserving scalar potential and analyse the possible real and complex vacua with emphasis on the cases in which the CP symmetry can be spontaneously broken. [...]
arXiv:1601.04654; CERN-TH-2016-013; CERN-TH-2016-013.-
2016-02-23 - 37 p.
Article from SCOAP3: scoap3-fulltext - PDF; scoap - PDF; Erratum: PDF; Fulltext: PDF; Springer Open Access article: PDF;
|
|
8.
|
|
9.
|
|
10.
|
|