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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 (up) 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 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:000440591500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3681
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Author Archidiacono, M.; Gariazzo, S.; Giunti, C.; Hannestad, S.; Tram, T.
Title Sterile neutrino self-interactions: H-0 tension and short-baseline anomalies Type Journal Article
Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 12 Issue 12 Pages 029 - 20pp
Keywords cosmological neutrinos; cosmological parameters from CMBR; particle physics – cosmology connection; physics of the early universe
Abstract (up) Sterile neutrinos with a mass in the eV range have been invoked as a possible explanation of a variety of short baseline (SBL) neutrino oscillation anomalies. However, if one considers neutrino oscillations between active and sterile neutrinos, such neutrinos would have been fully thermalised in the early universe, and would be therefore in strong conflict with cosmological bounds. In this study we first update cosmological bounds on the mass and energy density of eV-scale sterile neutrinos. We then perform an updated study of a previously proposed model in which the sterile neutrino couples to a new light pseudoscalar degree of freedom. Consistently with previous analyses, we find that the model provides a good fit to all cosmological data and allows the high value of H-0 measured in the local universe to be consistent with measurements of the cosmic microwave background. However, new high l polarisation data constrain the sterile neutrino mass to be less than approximately 1 eV in this scenario. Finally, we combine the cosmological bounds on the pseudoscalar model with a Bayesian inference analysis of SBL data and conclude that only a sterile mass in narrow ranges around 1 eV remains consistent with both cosmology and SBL data.
Address [Archidiacono, Maria] Univ Milan, Via G Celoria 16, I-20133 Milan, Italy, Email: maria.archidiacono@unimi.it;
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:000609105900015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4688
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Author Pallis, C.
Title Induced-gravity in inflation no-scale supergravity and beyond Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 08 Issue 8 Pages 057 - 20pp
Keywords inflation; supersymmetry and cosmology
Abstract (up) Supersymmetric versions of induced-gravity inflation are formulated within Supergravity (SUGRA) employing two gauge singlet chiral super fields. The proposed super-potential is uniquely determined by applying a continuous R and a discrete Z(n) symmetry. We select two types of logarithmic Kahler potentials, one associated with a no-scale-type SU(2, 1)/SU(2) x U(1)(R) x Z(n) Kahler manifold and one more generic. In both cases, imposing a lower bound on the parameter c R involved in the coupling between the inflaton and the Ricci scalar curvature – e.g. c(R) greater than or similar to 76, 105, 310 for n – 2, 3 and 6 respectively -, inflation can be attained even for subplanckian values of the inflaton while the corresponding effective theory respects the perturbative unitarity. In the case of no-scale SUGRA we show that, for every n, the inflationary observables remain unchanged and in agreement with the current data while the inflaton mass is predicted to be 3 . 10(13) GeV. Beyond no-scale SUGRA the inflationary observables depend mildly on n and crucially on the coefficient involved in the fourth order term of the Kahler potential which mixes the inflaton with the accompanying non-inflaton field.
Address [Pallis, C.] Univ Valencia, CSIC, Dept Fis Teor, E-46100 Burjassot, Spain, Email: kpallis@gen.auth.gr
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:000341848800057 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1944
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Author Cline, J.M.; Vincent, A.C.
Title Cosmological origin of anomalous radio background Type Journal Article
Year 2013 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 02 Issue 2 Pages 011 - 23pp
Keywords cosmology of theories beyond the SM; dark matter theory; extragalactic magnetic fields
Abstract (up) The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate several potential mechanisms and show that injection of relativistic electrons through late decays of a metastable particle can give rise to the observed excess radio spectrum through synchrotron emission. However, constraints from the cosmic microwave background (CMB) anisotropy, on injection of charged particles and on the primordial magnetic field, present a challenge. The simplest scenario is with a greater than or similar to 9 GeV particle decaying into e(+)e(-) at a redshift of z similar to 5, in a magnetic field of similar to 5 μG, which exceeds the CMB B-field constraints, unless the field was generated after decoupling. Decays into exotic millicharged particles can alleviate this tension, if they emit synchroton radiation in conjunction with a sufficiently large background magnetic field of a dark U(1)' gauge field.
Address [Cline, James M.] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada, Email: jcline@physics.mcgill.ca;
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:000315576400011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1361
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Author Dawson, K.S. et al; de Putter, R.; Mena, O.
Title The Baryon Oscillation Spectroscopic Survey of SDSS-III Type Journal Article
Year 2013 Publication Astronomical Journal Abbreviated Journal Astron. J.
Volume 145 Issue 1 Pages 10 - 41pp
Keywords cosmology: observations; surveys
Abstract (up) The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg(2) to measure BAO to redshifts z < 0.7. Observations of neutral hydrogen in the Ly alpha forest in more than 150,000 quasar spectra (g < 22) will constrain BAO over the redshift range 2.15 < z < 3.5. Early results from BOSS include the first detection of the large-scale three-dimensional clustering of the Ly alpha forest and a strong detection from the Data Release 9 data set of the BAO in the clustering of massive galaxies at an effective redshift z = 0.57. We project that BOSS will yield measurements of the angular diameter distance d(A) to an accuracy of 1.0% at redshifts z = 0.3 and z = 0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Ly alpha forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate D-A(z) and H-1(z) parameters to an accuracy of 1.9% at z similar to 2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS.
Address [Dawson, Kyle S.; Ahn, Christopher P.; Bolton, Adam S.; Brown, Peter J.; Brownstein, Joel R.; Harris, David W.; Montero-Dorta, Antonio D.; Olmstead, Matthew D.; Shu, Yiping; Zheng, Zheng] Univ Utah, Dept Phys & Astron, Salt Lake City, UT 84112 USA, Email: kdawson@astro.utah.edu
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 0004-6256 ISBN Medium
Area Expedition Conference
Notes WOS:000312251100010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1266
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