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Author Barenboim, G.; Park, W.I.
Title A full picture of large lepton number asymmetries of the Universe Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 048 - 10pp
Keywords (down) cosmological neutrinos; cosmology of theories beyond the SM; leptogenesis; physics of the early universe
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.
Address [Barenboim, Gabriela] Univ Valencia, CSIC, Dept Fis Teor, C Dr Moliner 50, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@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:000401806200048 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3148
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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 (down) cosmological neutrinos; cosmological parameters from CMBR; particle physics – cosmology connection; physics of the early universe
Abstract 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 Reig, M.; Valle, J.W.F.; Yamada, M.
Title Light majoron cold dark matter from topological defects and the formation of boson stars Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 09 Issue 9 Pages 029 - 25pp
Keywords (down) Cosmic strings; domain walls; monopoles; particle physics – cosmology connection; cosmology of theories beyond the SM; cosmological neutrinos
Abstract We show that for a relatively light majoron (<< 100 eV) non-thermal production from topological defects is an efficient production mechanism. Taking the type I seesaw as benchmark scheme, we estimate the primordial majoron abundance and determine the required parameter choices where it can account for the observed cosmological dark matter. The latter is consistent with the scale of unification. Possible direct detection of light majorons with future experiments such as PTOLEMY and the formation of boson stars from the majoron dark matter are also discussed.
Address [Reig, Mario; Valle, Jose W. F.] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Parc Cient Paterna,Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: mario.reig@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:000487690100005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4154
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Author Auclair, P.; Blanco-Pillado, J.J.; Figueroa, D.G.; Jenkins, A.C.; Lewicki, M.; Sakellariadou, M.; Sanidas, S.; Sousa, L.; Steer, D.A.; Wachter, J.M.; Kuroyanagi, S.
Title Probing the gravitational wave background from cosmic strings with LISA Type Journal Article
Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 034 - 50pp
Keywords (down) Cosmic strings; domain walls; monopoles; gravitational waves / sources; physics of the early universe; primordial gravitational waves (theory)
Abstract Cosmic string networks offer one of the best prospects for detection of cosmological gravitational waves (GWs). The combined incoherent GW emission of a large number of string loops leads to a stochastic GW background (SGWB), which encodes the properties of the string network. In this paper we analyze the ability of the Laser Interferometer Space Antenna (LISA) to measure this background, considering leading models of the string networks. We find that LISA will be able to probe cosmic strings with tensions G μgreater than or similar to O(10(-17)), improving by about 6 orders of magnitude current pulsar timing arrays (PTA) constraints, and potentially 3 orders of magnitude with respect to expected constraints from next generation PTA observatories. We include in our analysis possible modifications of the SGWB spectrum due to different hypotheses regarding cosmic history and the underlying physics of the string network. These include possible modifications in the SGWB spectrum due to changes in the number of relativistic degrees of freedom in the early Universe, the presence of a non-standard equation of state before the onset of radiation domination, or changes to the network dynamics due to a string inter-commutation probability less than unity. In the event of a detection, LISA's frequency band is well-positioned to probe such cosmic events. Our results constitute a thorough exploration of the cosmic string science that will be accessible to LISA.
Address [Auclair, Pierre; Steer, Daniele A.] Univ Paris, Lab Astroparticule & Cosmol, 10 Rue Alice Domon & Leonie Duquet, Paris 75013, France, Email: daniel.figueroa@cern.ch
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:000531476300035 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4393
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Author Maji, R.; Park, W.I.
Title Supersymmetric U(1)B-L flat direction and NANOGrav 15 year data Type Journal Article
Year 2024 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 01 Issue 1 Pages 015 - 19pp
Keywords (down) Cosmic strings; domain walls; monopoles; cosmological phase transitions; cosmology of theories beyond the SM; gravitational waves / sources
Abstract We show that, when connected with monopoles, the flat D-flat direction breaking the local U(1)B-L symmetry as an extension of the minimal supersymmetric standard model can be responsible for the signal of a stochastic gravitational wave background recently reported by NANOGrav collaborations, while naturally satisfying constraints at high frequency band. Thanks to the flatness of the direction, a phase of thermal inflation arises naturally. The reheating temperature is quite low, and suppresses signals at frequencies higher than the characteristic frequency set by the reheating temperature. Notably, forthcoming spaced based experiments such as LISA can probe the cutoff frequency, providing an indirect clue of the scale of soft SUSY-breaking mass parameter.
Address [Maji, Rinku] Jeonbuk Natl Univ, Dept Phys, Lab Symmetry & Struct Universe, Jeonju 54896, South Korea, Email: rinkumaji9792@gmail.com;
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:001147733000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5967
Permanent link to this record