| Records |
| Author |
Escudero, M.; Lopez-Pavon, J.; Rius, N.; Sandner, S. |
Title  |
Relaxing cosmological neutrino mass bounds with unstable neutrinos |
Type |
Journal Article |
| Year |
2020 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
12 |
Issue |
12 |
Pages |
119 - 44pp |
| Keywords |
Beyond Standard Model; Cosmology of Theories beyond the SM; Neutrino Physics |
| Abstract |
At present, cosmological observations set the most stringent bound on the neutrino mass scale. Within the standard cosmological model (Lambda CDM), the Planck collaboration reports Sigma m(v)< 0.12 eV at 95 % CL. This bound, taken at face value, excludes many neutrino mass models. However, unstable neutrinos, with lifetimes shorter than the age of the universe <tau>(nu) less than or similar to t(U), represent a particle physics avenue to relax this constraint. Motivated by this fact, we present a taxonomy of neutrino decay modes, categorizing them in terms of particle content and final decay products. Taking into account the relevant phenomenological bounds, our analysis shows that 2-body decaying neutrinos into BSM particles are a promising option to relax cosmological neutrino mass bounds. We then build a simple extension of the type I seesaw scenario by adding one sterile state nu (4) and a Goldstone boson phi, in which nu (i)-> nu (4)phi decays can loosen the neutrino mass bounds up to Sigma m(v) similar to 1 eV, without spoiling the light neutrino mass generation mechanism. Remarkably, this is possible for a large range of the right-handed neutrino masses, from the electroweak up to the GUT scale. We successfully implement this idea in the context of minimal neutrino mass models based on a U(1)(mu-tau) flavor symmetry, which are otherwise in tension with the current bound on Sigma m(v). |
| Address |
[Escudero, Miguel] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: miguel.escudero@kcl.ac.uk; |
| 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:000601400500005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4661 |
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| Author |
Folgado, M.G.; Gomez-Vargas, G.A.; Rius, N.; Ruiz de Austri, R. |
| Title |
Probing the sterile neutrino portal to Dark Matter with gamma rays |
Type |
Journal Article |
| Year |
2018 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
| Volume |
08 |
Issue |
8 |
Pages |
002 - 20pp |
| Keywords |
dark matter theory; particle physics – cosmology connection; neutrino theory |
| Abstract |
Sterile neutrinos could provide a link between the Standard Model particles and a dark sector, besides generating active neutrino masses via the seesaw mechanism type I. We show that, if dark matter annihilation into sterile neutrinos determines its observed relic abundance, it is possible to explain the Galactic Center gamma-ray excess reported by the Fermi-LAT Collaboration as due to an astrophysical component plus dark matter annihilations. We observe that sterile neutrino portal to dark matter provides an impressively good fit, with a p-value of 0.78 in the best fit point, to the Galactic Center gamma-ray flux, for DM masses in the range (40-80) GeV and sterile neutrino masses 20 GeV less than or similar to M-N < M-DM. Such values are compatible with the limits from Fermi-LAT observations of the dwarfs spheroidal galaxies in the Milky Way halo, which rule out dark matter masses below similar to 50 GeV ( 90 GeV), for sterile neutrino masses M-N less than or similar to MDM ( M-N << M-DM). We also estimate the impact of AMS-02 anti-proton data on this scenario. |
| Address |
[Folgado, Miguel G.; Rius, Nuria; Ruiz de Austri, Roberto] Univ Valencia, CSIC, Dept Fis Teor, C-Catedratico Jose Beltran 2, E-46980 Paterna, Spain, Email: migarfol@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 |
1475-7516 |
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:000440591500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3681 |
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| Author |
Chun, E.J.; Cvetic, G.; Dev, P.S.B.; Drewes, M.; Fong, C.S.; Garbrecht, B.; Hambye, T.; Harz, J.; Hernandez, P.; Kim, C.S.; Molinaro, E.; Nardi, E.; Racker, J.; Rius, N.; Zamora-Saa, J. |
| Title |
Probing leptogenesis |
Type |
Journal Article |
| Year |
2018 |
Publication |
International Journal of Modern Physics A |
Abbreviated Journal |
Int. J. Mod. Phys. A |
| Volume |
33 |
Issue |
5-6 |
Pages |
1842005 - 99pp |
| Keywords |
Neutrino interactions; nonstandard-model neutrinos; right-handed neutrinos; extensions of electroweak gauge sector; supersymmetric models |
| Abstract |
The focus of this paper lies on the possible experimental tests of leptogenesis scenarios. We consider both leptogenesis generated from oscillations, as well as leptogenesis from out-of-equilibrium decays. As the Akhmedov-Rubakov-Smirnov (ARS) mechanism allows for heavy neutrinos in the GeV range, this opens up a plethora of possible experimental tests, e.g. at neutrino oscillation experiments, neutrinoless double beta decay, and direct searches for neutral heavy leptons at future facilities. In contrast, testing leptogenesis from out-of-equilibrium decays is a quite difficult task. We comment on the necessary conditions for having successful leptogenesis at the TeV-scale. We further discuss possible realizations and their model specific testability in extended seesaw models, models with extended gauge sectors, and supersymmetric leptogenesis. Not being able to test high-scale leptogenesis directly, we present a way to falsify such scenarios by focusing on their washout processes. This is discussed specifically for the left-right symmetric model and the observation of a heavy W-R, as well as model independently when measuring Delta L = 2 washout processes at the LHC or neutrinoless double beta decay. |
| Address |
[Chun, E. J.] Korea Inst Adv Study, Seoul 02455, South Korea, Email: jharz@lpthe.jussieu.fr |
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Thesis |
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| Publisher |
World Scientific Publ Co Pte 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 |
0217-751x |
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:000426586100006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3507 |
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| Author |
Sandner, S.; Hernandez, P.; Lopez-Pavon, J.; Rius, N. |
| Title |
Predicting the baryon asymmetry with degenerate right-handed neutrinos |
Type |
Journal Article |
| Year |
2023 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
11 |
Issue |
11 |
Pages |
153 - 37pp |
| Keywords |
Baryo-and Leptogenesis; Sterile or Heavy Neutrinos; Early Universe Particle Physics |
| Abstract |
We consider the generation of a baryon asymmetry in an extension of the Standard Model with two singlet Majorana fermions that are degenerate above the electroweak phase transition. The model can explain neutrino masses as well as the observed matter-antimatter asymmetry, for masses of the heavy singlets below the electroweak scale. The only physical CP violating phases in the model are those in the PMNS mixing matrix, i.e. the Dirac phase and a Majorana phase that enter light neutrino observables. We present an accurate analytic approximation for the baryon asymmetry in terms of CP flavour invariants, and derive the correlations with neutrino observables. We demonstrate that the measurement of CP violation in neutrino oscillations as well as the mixings of the heavy neutral leptons with the electron, muon and tau flavours suffice to pin down the matter-antimatter asymmetry from laboratory measurements. |
| Address |
[Sandner, S.] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest,Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: stefan.sandner@ific.uv.es; |
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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:001111979900002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
5869 |
| Permanent link to this record |
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| Author |
Aparici, A.; Herrero-Garcia, J.; Rius, N.; Santamaria, A. |
| Title |
On the nature of the fourth generation neutrino and its implications |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
07 |
Issue |
7 |
Pages |
030 - 31pp |
| Keywords |
Beyond Standard Model; Neutrino Physics |
| Abstract |
We consider the neutrino sector of a Standard Model with four generations. While the three light neutrinos can obtain their masses from a variety of mechanisms with or without new neutral fermions, fourth-generation neutrinos need at least one new relatively light right-handed neutrino. If lepton number is not conserved this neutrino must have a Majorana mass term whose size depends on the underlying mechanism for lepton number violation. Majorana masses for the fourth-generation neutrinos induce relative large two-loop contributions to the light neutrino masses which could be even larger than the cosmological bounds. This sets strong limits on the mass parameters and mixings of the fourth-generation neutrinos. |
| Address |
[Aparici, Alberto] Univ Valencia, CSIC, Dept Fis Teor, Valencia 46071, Spain, Email: alberto.aparici@uv.es; |
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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 Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1126-6708 |
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:000307298400030 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
1157 |
| Permanent link to this record |
