Records |
Author |
Morisi, S.; Peinado, E. |
Title |
Admixture of quasi-Dirac and Majorana neutrinos with tri-bimaximal mixing |
Type |
Journal Article |
Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
701 |
Issue |
4 |
Pages |
451-457 |
Keywords |
Neutrinoless double beta decay; Neutrino masses and mixings; Flavor symmetries; Tri-bimaximal mixing; Neutrino hierarchy; Discrete symmetries |
Abstract |
We propose a realization of the so-called bimodal/schizophrenic model proposed recently. We assume 54, the permutation group of four objects as flavor symmetry giving tri-bimaximal lepton mixing at leading order. In these models the second massive neutrino state is assumed quasi-Dirac and the remaining neutrinos are Majorana states. In the case of inverse mass hierarchy, the lower bound on the neutrinoless double beta decay parameter m(ee) is about two times that of the usual lower bound, within the range of sensitivity of the next generation of experiments. |
Address |
[Morisi, S; Peinado, E] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, E-46071 Valencia, Spain, Email: morisi@ific.uv.es |
Corporate Author |
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Thesis |
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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 |
0370-2693 |
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:000292994100011 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
700 |
Permanent link to this record |
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Author |
Emmanuel-Costa, D.; Simoes, C.; Tortola, M. |
Title |
The minimal adjoint-SU (5) x Z(4) GUT model |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
10 |
Issue |
10 |
Pages |
054 - 30pp |
Keywords |
Neutrino Physics; GUT; Discrete and Finite Symmetries |
Abstract |
An extension of the adjoint SU (5) model with a flavour symmetry based on the Z(4) group is investigated. The Z(4) symmetry is introduced with the aim of leading the up-and down-quark mass matrices to the Nearest-Neighbour-Interaction form. As a consequence of the discrete symmetry embedded in the SU (5) gauge group, the charged lepton mass matrix also gets the same form. Within this model, light neutrinos get their masses through type-I, type-III and one-loop radiative seesaw mechanisms, implemented, respectively, via a singlet, a triplet and an octet from the adjoint fermionic 24 fields. It is demonstrated that the neutrino phenomenology forces the introduction of at least three 24 fermionic multiplets. The symmetry SU (5) x Z(4) allows only two viable zero textures for the effective neutrino mass matrix. It is showed that one texture is only compatible with normal hierarchy and the other with inverted hierarchy in the light neutrino mass spectrum. Finally, it is also demonstrated that Z(4) freezes out the possibility of proton decay through exchange of coloured Higgs triplets at tree-level. |
Address |
[Emmanuel-Costa, D.; Simoes, C.] Univ Lisbon, Inst Super Tecn, Dept Fis, P-1049001 Lisbon, Portugal, Email: david.costa@ist.utl.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 |
1029-8479 |
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:000325495200002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1604 |
Permanent link to this record |
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Author |
Bernabeu, J.; Segarra, A. |
Title |
Stimulated transitions in resonant atom Majorana mixing |
Type |
Journal Article |
Year |
2018 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
02 |
Issue |
2 |
Pages |
017 - 16pp |
Keywords |
Neutrino Physics; Beyond Standard Model; Global Symmetries |
Abstract |
Massive neutrinos demand to ask whether they are Dirac or Majorana particles. Majorana neutrinos are an irrefutable proof of physics beyond the Standard Model. Neutrinoless double electron capture is not a process but a virtual Delta L = 2 mixing between a parent (A)Z atom and a daughter (A)(Z – 2) excited atom with two electron holes. As a mixing between two neutral atoms and the observable signal in terms of emitted two-hole X-rays, the strategy, experimental signature and background are different from neutrinoless double beta decay. The mixing is resonantly enhanced for almost degeneracy and, under these conditions, there is no irreducible background from the standard two-neutrino channel. We reconstruct the natural time history of a nominally stable parent atom since its production either by nature or in the laboratory. After the time periods of atom oscillations and the decay of the short-lived daughter atom, at observable times the relevant 'stationary" states are the mixed metastable long-lived state and the non-orthogonal short-lived excited state, as well as the ground state of the daughter atom. We find that they have a natural population inversion which is most appropriate for exploiting the bosonic nature of the observed atomic transitions radiation. Among different observables of the atom Majorana mixing, we include the enhanced rate of stimulated X-ray emission from the long-lived metastable state by a high-intensity X-ray beam: a gain factor of 100 can be envisaged at current XFEL facilities. On the other hand, the historical population of the daughter atom ground state can be probed by exciting it with a current pulsed optical laser, showing the characteristic absorption lines: the whole population can be excited in a shorter time than typical pulse duration. |
Address |
[Bernabeu, Jose] Univ Valencia, CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@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 |
1029-8479 |
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:000424101600008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
3475 |
Permanent link to this record |
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Author |
Centelles Chulia, S.; Cepedello, R.; Peinado, E.; Srivastava, R. |
Title |
Scotogenic dark symmetry as a residual subgroup of Standard Model symmetries |
Type |
Journal Article |
Year |
2020 |
Publication |
Chinese Physics C |
Abbreviated Journal |
Chin. Phys. C |
Volume |
44 |
Issue |
8 |
Pages |
083110 - 7pp |
Keywords |
neutrino masses; dark matter; symmetries; scotogenic |
Abstract |
We demonstrate that a scotogenic dark symmetry can be obtained as a residual subgroup of the global U(1)(B-L) symmetry already present in the Standard Model. In addition, we propose a general framework in which the U(1)(B-L) symmetry is spontaneously broken into an even Z(2n) subgroup, setting the general conditions for neutrinos to be Majorana and for dark matter stability to exist in terms of the residual Z(2n). As an example, under this general framework, we build a class of simple models where, in a scotogenic manner, the dark matter candidate is the lightest particle running inside the mass loop of a neutrino. The global U(1)(B-L) symmetry in our framework, being anomaly free, can also be gauged in a straightforward manner leading to a richer phenomenology. |
Address |
[Chulia, Salvador Centelles; Cepedello, Ricardo; Srivastava, Rahul] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna C Catedratico Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: salcen@ific.uv.es; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
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 |
1674-1137 |
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:000557423400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4494 |
Permanent link to this record |
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Author |
Botella, F.J.; Branco, G.C.; Rebelo, M.N. |
Title |
Minimal flavour violation and multi-Higgs models |
Type |
Journal Article |
Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
687 |
Issue |
2-3 |
Pages |
194-200 |
Keywords |
Multi-Higgs models; Minimal Flavour Violation; FCNC; Flavour symmetries |
Abstract |
We propose an extension of the hypothesis of Minimal Flavour Violation (MFV) to general multi-Higgs models without the assumption of Natural Flavour Conservation (NFC) in the Higgs sector. We study in detail under what conditions the neutral Higgs couplings are only functions of V-CKM and propose a MFV expansion for the neutral Higgs couplings to fermions. |
Address |
[Branco, G. C.; Rebelo, M. N.] Inst Super Tecn, Dept Fis, P-1049001 Lisbon, Portugal, Email: fbotella@uv.es |
Corporate Author |
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Thesis |
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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 |
0370-2693 |
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 |
ISI:000277070800019 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
457 |
Permanent link to this record |