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Author |
Vincent, A.C.; Fernandez Martinez, E.; Hernandez, P.; Mena, O.; Lattanzi, M. |
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Title |
Revisiting cosmological bounds on sterile neutrinos |
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 |
04 |
Issue |
4 |
Pages  |
006 - 23pp |
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Keywords |
particle physics – cosmology connection; cosmological neutrinos; cosmology of theories beyond the SM |
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Abstract |
We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R-CMB and the sound horizon r(s) from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin(2) theta less than or similar to 0.026(m(s)/eV)(-2). |
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Address |
[Vincent, Aaron C.] Univ Durham, Dept Phys, IPPP, Durham DH1 3LE, England, Email: aaron.vincent@durham.ac.uk; |
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Publisher |
Iop Publishing Ltd |
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English |
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Series Volume |
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ISSN |
1475-7516 |
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Notes |
WOS:000355742500007 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
2261 |
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Author |
Boubekeur, L.; Choi, K.Y.; Ruiz de Austri, R.; Vives, O. |
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Title |
The degenerate gravitino scenario |
Type |
Journal Article |
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Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
04 |
Issue |
4 |
Pages |
005 - 26pp |
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Keywords |
dark matter theory; leptogenesis; supersymmetry and cosmology; cosmology of theories beyond the SM |
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Abstract |
In this work, we explore the “degenerate gravitino” scenario where the mass difference between the gravitino and the lightest MSSM particle is much smaller than the gravitino mass itself. In this case, the energy released in the decay of the next to lightest sypersymmetric particle (NLSP) is reduced. Consequently the cosmological and astrophysical constraints on the gravitino abundance, and hence on the reheating temperature, become softer than in the usual case. On the other hand, such small mass splittings generically imply a much longer lifetime for the NLSP. We find that, in the constrained MSSM (CMSSM), for neutralino LSP or NLSP, reheating temperatures compatible with thermal leptogenesis are reached for small splittings of order 10(-2) GeV. While for stau NLSP, temperatures of T-RH similar or equal to 4 x 10(9) GeV can be obtained even for splittings of order of tens of GeVs. This “degenerate gravitino” scenario offers a possible way out to the gravitino problem for thermal leptogenesis in supersymmetric theories. |
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Address |
[Boubekeur, Lotfi; Vives, Oscar] Univ Valencia, Dept Fis Teor, E-46100 Burjassot, Spain, Email: lotfi.boubekeur@uv.es |
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Publisher |
Iop Publishing Ltd |
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Language |
English |
Summary Language |
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Original Title |
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ISSN |
1475-7516 |
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Notes |
ISI:000277684600028 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ elepoucu @ |
Serial |
453 |
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Author |
LISA Cosmology Working Group (Auclair, P. et al); Figueroa, D.G. |
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Title |
Cosmology with the Laser Interferometer Space Antenna |
Type |
Journal Article |
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Year |
2023 |
Publication |
Living Reviews in Relativity |
Abbreviated Journal |
Living Rev. Relativ. |
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Volume |
26 |
Issue |
1 |
Pages |
5 - 254pp |
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Keywords |
Laser Interferometer Space Antenna (LISA); Cosmology |
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Abstract |
The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational-wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational-wave observations by LISA to probe the universe. |
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Address |
[Auclair, Pierre; Caprini, Chiara; Mangiagli, Alberto; Papanikolaou, Theodoros; Pol, Alberto Roper; Steer, Daniele A.; Vennin, Vincent; Petiteau, Antoine] Univ Paris, CNRS, Lab Astroparticule & Cosmol, F-75013 Paris, France, Email: chairscoswg@gmail.com |
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Publisher |
Springer Int Publ Ag |
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English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
2367-3613 |
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Notes |
WOS:001063967800001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5755 |
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Author |
Jackson, C.B.; Servant, G.; Shaughnessy, G.; Tait, T.M.P.; Taoso, M. |
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Title |
Higgs in space! |
Type |
Journal Article |
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Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
04 |
Issue |
4 |
Pages |
004 - 29pp |
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Keywords |
dark matter theory; dark matter experiments; gamma ray experiments; cosmology of theories beyond the SM |
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Abstract |
We consider the possibility that the Higgs can be produced in dark matter annihilations, appearing as a line in the spectrum of gamma rays at an energy determined by the masses of the WIMP and the Higgs itself. We argue that this phenomenon occurs generally in models in which the the dark sector has large couplings to the most massive states of the SM and provide a simple example inspired by the Randall-Sundrum vision of dark matter, whose 4d dual corresponds to electroweak symmetry-breaking by strong dynamics which respect global symmetries that guarantee a stable WIMP. The dark matter is a Dirac fermion that couples to a Z' acting as a portal to the Standard Model through its strong coupling to top quarks. Annihilation into light standard model degrees of freedom is suppressed and generates a feeble continuum spectrum of gamma rays. Loops of top quarks mediate annihilation into gamma Z, gamma h, and gamma Z', providing a forest of lines in the spectrum. Such models can be probed by the Fermi/GLAST satellite and ground-based Air Cherenkov telescopes. |
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Address |
[Jackson, C. B.; Shaughnessy, Gabe; Tait, Tim M. P.] Argonne Natl Lab, HEP Div, Argonne, IL 60439 USA, Email: jackson@hep.anl.gov |
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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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Area |
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Expedition |
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Conference |
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Notes |
ISI:000277684600029 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ elepoucu @ |
Serial |
454 |
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Author |
Reid, B.A.; Verde, L.; Jimenez, R.; Mena, O. |
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Title |
Robust neutrino constraints by combining low redshift observations with the CMB |
Type |
Journal Article |
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Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
01 |
Issue |
1 |
Pages |
003 - 21pp |
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Keywords |
cluster counts; cosmological parameters from LSS; neutrino masses from cosmology; cosmological parameters from CMBR |
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Abstract |
We illustrate how recently improved low-redshift cosmological measurements can tighten constraints on neutrino properties. In particular we examine the impact of the assumed cosmological model on the constraints. We first consider the new HST H-0 = 74.2 +/- 3.6 measurement by Riess et al. (2009) and the sigma(8)(Omega(m)/0.25)(0.41) = 0.832 +/- 0.033 constraint from Rozo et al. (2009) derived from the SDSS maxBCG Cluster Catalog. In a ACDM model and when combined with WMAP5 constraints, these low-redshift measurements constrain Sigma m(v) < 0.4 eV at the 95% confidence level. This bound does not relax when allowing for the running of the spectral index or for primordial tensor perturbations. When adding also Supernovae and BAO constraints, we obtain a 95% upper limit of Sigma m(v) < 0.3eV. We test the sensitivity of the neutrino mass constraint to the assumed expansion history by both allowing a dark energy equation of state parameter w not equal -1 and by studying a model with coupling between dark energy and dark matter, which allows for variation in w, Omega(k), and dark coupling strength xi. When combining CMB, H-0 and the SDSS LRG halo power spectrum from Reid et al. 2009, we find that in this very general model, Sigma m(v) < 0.51 eV with 95% confidence. If we allow the number of relativistic species N-rel to vary in a ACDM model with Sigma m(v) = 0, we find N-rel = 3.76(-0.68)(+0.63)(+1.38 -1.21) for the 68% and 95% confidence intervals. We also report prior-independent constraints, which are in excellent agreement with the Bayesian constraints. |
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Address |
[Reid, Beth A.] Univ Barcelona, Inst Sci Cosmos ICC, E-08028 Barcelona, Spain, Email: beth.ann.reid@gmail.com |
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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 |
ISI:000273314600008 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ elepoucu @ |
Serial |
511 |
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