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Author Di Bari, P.; Ludl, P.O.; Palomares-Ruiz, S.
Title Unifying leptogenesis, dark matter and high-energy neutrinos with right-handed neutrino mixing via Higgs portal Type Journal Article
Year (down) 2016 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 11 Issue 11 Pages 044 - 41pp
Keywords dark matter theory; leptogenesis; physics of the early universe; ultra high energy photons and neutrinos
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.
Address [Di Bari, Pasquale; Ludl, Patrick Otto] Univ Southampton, Phys & Astron, Southampton SO17 1BJ, Hants, England, Email: P.Di-Bari@soton.ac.uk;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000397734100044 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3020
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Author Aoki, M.; Toma, T.; Vicente, A.
Title Non-thermal production of minimal dark matter via right-handed neutrino decay Type Journal Article
Year (down) 2015 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 09 Issue 9 Pages 063 - 19pp
Keywords dark matter theory; gamma ray theory; particle physics – cosmology connection; physics of the early universe
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.
Address [Aoki, Mayumi] Kanazawa Univ, Inst Theoret Phys, Kanazawa, Ishikawa 9201192, Japan, Email: mayumi@hep.s.kanazawa-u.ac.jp;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000365690000063 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2479
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Author Easther, R.; Price, L.C.; Rasero, J.
Title Inflating an inhomogeneous universe Type Journal Article
Year (down) 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 08 Issue 8 Pages 041 - 16pp
Keywords inflation; initial conditions and eternal universe; physics of the early universe
Abstract While cosmological inflation can erase primordial inhomogeneities, it is possible that inflation may not begin in a significantly inhomogeneous universe. This issue is particularly pressing in multifield scenarios, where even the homogeneous dynamics may depend sensitively on the initial configuration. This paper presents an initial survey of the onset of inflation in multifield models, via qualitative lattice-based simulations that do not include local gravitational backreaction. Using hybrid inflation as a test model, our results suggest that small subhorizon inhomogeneities do play a key role in determining whether inflation begins in multifield scenarios. Interestingly, some configurations which do not inflate in the homogeneous limit “succeed” after inhomogeneity is included, while other initial configurations which inflate in the homogeneous limit “fail” when inhomogeneity is added.
Address [Easther, Richard; Price, Layne C.] Univ Auckland, Dept Phys, Auckland, New Zealand, Email: r.easther@auckland.ac.nz;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000341848800041 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1943
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Author Mangano, G.; Miele, G.; Pastor, S.; Pisanti, O.; Sarikas, S.
Title Updated BBN bounds on the cosmological lepton asymmetry for non-zero theta(13) Type Journal Article
Year (down) 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 708 Issue 1-2 Pages 1-5
Keywords Neutrinos; Physics of the early Universe; Primordial asymmetries
Abstract We discuss the bounds on the cosmological lepton number from Big Bang Nucleosynthesis (BBN), in light of recent evidences for a large value of the neutrino mixing angle theta(13), sin(2) theta(13) greater than or similar to 0.01 at 2 sigma. The largest asymmetries for electron and mu, tau neutrinos compatible with He-4 and H-2 primordial yields are computed versus the neutrino mass hierarchy and mixing angles. The flavour oscillation dynamics is traced till the beginning of BBN and neutrino distributions after decoupling are numerically computed. The latter contains in general, non-thermal distortion due to the onset of flavour oscillations driven by solar squared mass difference in the temperature range where neutrino scatterings become inefficient to enforce thermodynamical equilibrium. Depending on the value of theta(13), this translates into a larger value for the effective number of neutrinos, N-eff. Upper bounds on this parameter are discussed for both neutrino mass hierarchies. Values for N-eff which are large enough to be detectable by the Planck experiment are found only for the (presently disfavoured) range sin(2) theta(13) <= 0.01.
Address [Pastor, Sergio] Univ Valencia, CSIC, Inst Fis Corpuscular, Ed Inst Invest, E-46071 Valencia, Spain, Email: pastor@ific.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:000301310000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 967
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Author Blennow, M.; Fernandez-Martinez, E.; Mena, O.; Redondo, J.; Serra, E.P.
Title Asymmetric Dark Matter and Dark Radiation Type Journal Article
Year (down) 2012 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 022 - 23pp
Keywords dark matter theory; particle physics – cosmology connection; physics of the early universe
Abstract Asymmetric Dark Matter (ADM) models invoke a particle-antiparticle asymmetry, similar to the one observed in the Baryon sector, to account for the Dark Matter (DM) abundance. Both asymmetries are usually generated by the same mechanism and generally related, thus predicting DM masses around 5 GeV in order to obtain the correct density. The main challenge for successful models is to ensure efficient annihilation of the thermally produced symmetric component of such a light DM candidate without violating constraints from collider or direct searches. A common way to overcome this involves a light mediator, into which DM can efficiently annihilate and which subsequently decays into Standard Model particles. Here we explore the scenario where the light mediator decays instead into lighter degrees of freedom in the dark sector that act as radiation in the early Universe. While this assumption makes indirect DM searches challenging, it leads to signals of extra radiation at BBN and CMB. Under certain conditions, precise measurements of the number of relativistic species, such as those expected from the Planck satellite, can provide information on the structure of the dark sector. We also discuss the constraints of the interactions between DM and Dark Radiation from their imprint in the matter power spectrum.
Address [Blennow, Mattias] Max Planck Inst Kernphys, D-69117 Heidelberg, Germany, Email: Mattias.Blennow@mpi-hd.mpg.de;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000307079600033 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1165
Permanent link to this record