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Records |
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Author |
Aoki, M.; Toma, T.; Vicente, A. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Non-thermal production of minimal dark matter via right-handed neutrino decay |
Type |
Journal Article |
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Year |
2015 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
09 |
Issue |
9 |
Pages |
063 - 19pp |
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Keywords |
dark matter theory; gamma ray theory; particle physics – cosmology connection; physics of the early universe |
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Abstract |
Minimal Dark Matter (MDM) stands as one of the simplest dark matter scenarios. In MDM models, annihilation and co-annihilation processes among the members of the MDM multiplet are usually very efficient, pushing the dark matter mass above O(10) TeV in order to reproduce the observed dark matter relic density. Motivated by this little drawback, in this paper we consider an extension of the MDM scenario by three right-handed neutrinos. Two specific choices for the MDM multiplet are studied: a fermionic SU(2)(L) quintuplet and a scalar SU(2)(L) septuplet. The lightest right-handed neutrino, with tiny Yukawa couplings, never reaches thermal equilibrium in the early universe and is produced by freeze-in. This creates a link between dark matter and neutrino physics: dark matter can be non-thermally produced by the decay of the lightest right-handed neutrino after freeze-out, allowing to lower significantly the dark matter mass. We discuss the phenomenology of the non-thermally produced MDM and, taking into account significant Sommerfeld corrections, we find that the dark matter mass must have some specific values in order not to be in conflict with the current bounds from gamma-ray observations. |
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Address |
[Aoki, Mayumi] Kanazawa Univ, Inst Theoret Phys, Kanazawa, Ishikawa 9201192, Japan, Email: mayumi@hep.s.kanazawa-u.ac.jp; |
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Publisher |
Iop Publishing Ltd |
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English |
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ISSN |
1475-7516 |
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Conference |
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Notes |
WOS:000365690000063 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
2479 |
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Permanent link to this record |
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Author |
Di Bari, P.; Ludl, P.O.; Palomares-Ruiz, S. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Unifying leptogenesis, dark matter and high-energy neutrinos with right-handed neutrino mixing via Higgs portal |
Type |
Journal Article |
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Year |
2016 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
11 |
Issue |
11 |
Pages |
044 - 41pp |
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Keywords |
dark matter theory; leptogenesis; physics of the early universe; ultra high energy photons and neutrinos |
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Abstract |
We revisit a model in which neutrino masses and mixing are described by a two right-handed (RH) neutrino seesaw scenario, implying a strictly hierarchical light neutrino spectrum. A third decoupled RH neutrino, N-DM with mass M-DM, plays the role of cold dark matter (DM) and is produced by the mixing with a source RH neutrino, Ns with mass M-S, induced by Higgs portal interactions. The same interactions are also responsible for N-DM decays. We discuss in detail the constraints coming from DM abundance and stability conditions showing that in the hierarchical case, for M-DM >> M-S, there is an allowed window on M-DM values necessarily implying a contribution, from DM decays, to the high-energy neutrino flux recently detected by IceCube. We also show how the model can explain the matter-antimatter asymmetry of the Universe via leptogenesis in the quasi-degenerate limit. In this case, the DM mass should be within the range 300 GeV less than or similar to M-S < M-DM < 10PeV. We discuss the specific properties of this high-energy neutrino flux and show the predicted event spectrum for two exemplary cases. Although DM decays, with a relatively hard spectrum, cannot account for all the IceCube high-energy data, we illustrate how this extra source of high-energy neutrinos could reasonably explain some potential features in the observed spectrum. In this way, this represents a unified scenario for leptogenesis and DM that could be tested during the next years with more high-energy neutrino events. |
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Address |
[Di Bari, Pasquale; Ludl, Patrick Otto] Univ Southampton, Phys & Astron, Southampton SO17 1BJ, Hants, England, Email: P.Di-Bari@soton.ac.uk; |
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Iop Publishing Ltd |
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English |
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ISSN |
1475-7516 |
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Notes |
WOS:000397734100044 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3020 |
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Permanent link to this record |
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Author |
de Salas, P.F.; Pastor, S. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Relic neutrino decoupling with flavour oscillations revisited |
Type |
Journal Article |
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Year |
2016 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages |
051 - 18pp |
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Keywords |
cosmological neutrinos; particle physics – cosmology connection; physics of the; early universe; neutrino properties |
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Abstract |
We study the decoupling process of neutrinos in the early universe in the presence of three-flavour oscillations. The evolution of the neutrino spectra is found by solving the corresponding momentum-dependent kinetic equations for the neutrino density matrix, including for the first time the proper collision integrals for both diagonal and off-diagonal elements. This improved calculation modifies the evolution of the off-diagonal elements of the neutrino density matrix and changes the deviation from equilibrium of the frozen neutrino spectra. However, it does not vary the contribution of neutrinos to the cosmological energy density in the form of radiation, usually expressed in terms of the effective number of neutrinos, N-eff. We find a value of N-eff = 3.045, in agreement with previous theoretical calculations and consistent with the latest analysis of Planck data. This result does not depend on the ordering of neutrino masses. We also consider the effect of non-standard neutrino-electron interactions (NSI), predicted in many theoretical models where neutrinos acquire mass. For two sets of NSI parameters allowed by present data, we find that Neff can be reduced down to 3.040 or enhanced up to 3.059. |
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Address |
[de Salas, Pablo F.; Pastor, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient UV,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: pabrerde@ific.uv.es; |
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Iop Publishing Ltd |
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English |
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1475-7516 |
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Notes |
WOS:000381830000052 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
no |
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Call Number |
IFIC @ pastor @ |
Serial |
2784 |
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Permanent link to this record |
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Author |
Barenboim, G.; Park, W.I. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
A full picture of large lepton number asymmetries of the Universe |
Type |
Journal Article |
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Year |
2017 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
04 |
Issue |
4 |
Pages |
048 - 10pp |
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Keywords |
cosmological neutrinos; cosmology of theories beyond the SM; leptogenesis; physics of the early universe |
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Abstract |
A large lepton number asymmetry of O(0.1-1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 30. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10(-2) -10(2)) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m(phi) greater than or similar to O(10) TeV and phi(0) greater than or similar to O(10(14)) GeV, respectively. |
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Address |
[Barenboim, Gabriela] Univ Valencia, CSIC, Dept Fis Teor, C Dr Moliner 50, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@uv.es; |
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Publisher |
Iop Publishing Ltd |
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English |
Summary Language |
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ISSN |
1475-7516 |
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Notes |
WOS:000401806200048 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3148 |
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Permanent link to this record |
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Author |
Beltran Jimenez, J.; Heisenberg, L.; Olmo, G.J.; Rubiera-Garcia, D. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Born-Infeld inspired modifications of gravity |
Type |
Journal Article |
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Year |
2018 |
Publication |
Physics Reports |
Abbreviated Journal |
Phys. Rep. |
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Volume |
727 |
Issue |
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Pages |
1-129 |
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Keywords |
Born-Infeld gravity; Astrophysics; Black holes; Cosmology; Early universe; Compact objects; Singularities |
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Abstract |
General Relativity has shown an outstanding observational success in the scales where it has been directly tested. However, modifications have been intensively explored in the regimes where it seems either incomplete or signals its own limit of validity. In particular, the breakdown of unitarity near the Planck scale strongly suggests that General Relativity needs to be modified at high energies and quantum gravity effects are expected to be important. This is related to the existence of spacetime singularities when the solutions of General Relativity are extrapolated to regimes where curvatures are large. In this sense, Born-Infeld inspired modifications of gravity have shown an extraordinary ability to regularise the gravitational dynamics, leading to non-singular cosmologies and regular black hole spacetimes in a very robust manner and without resorting to quantum gravity effects. This has boosted the interest in these theories in applications to stellar structure, compact objects, inflationary scenarios, cosmological singularities, and black hole and wormhole physics, among others. We review the motivations, various formulations, and main results achieved within these theories, including their observational viability, and provide an overview of current open problems and future research opportunities. |
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Address |
[Beltran Jimenez, Jose] Univ Autonoma Madrid, CSIC, Inst Fis Teor, E-28049 Madrid, Spain, Email: jose.beltran@uam.es; |
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Publisher |
Elsevier Science Bv |
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English |
Summary Language |
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Abbreviated Series Title |
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ISSN |
0370-1573 |
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Notes |
WOS:000425482900001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3497 |
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Permanent link to this record |