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Author Giusarma, E.; Di Valentino, E.; Lattanzi, M.; Melchiorri, A.; Mena, O.
Title Relic neutrinos, thermal axions, and cosmology in early 2014 Type Journal Article
Year 2014 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 90 Issue 4 Pages (down) 043507 - 17pp
Keywords
Abstract We present up-to-date cosmological bounds on the sum of active neutrino masses as well as on extended cosmological scenarios with additional thermal relics, as thermal axions or sterile neutrino species. Our analyses consider all the current available cosmological data in the beginning of year 2014, including the very recent and most precise baryon acoustic oscillation measurements from the Baryon Oscillation Spectroscopic Survey. In the minimal three-active-neutrino scenario, we find Sigma m(nu) < 0.22 eV at 95% C.L. from the combination of cosmic microwave background (CMB), baryon acoustic oscillation, and Hubble Space Telescope measurements of the Hubble constant. A nonzero value for the sum of the three active neutrino masses of similar to 0.3 eV is significantly favored at more than three standard deviations when adding the constraints on s 8 and Om from the Planck cluster catalog on galaxy number counts. This preference for nonzero thermal relic masses disappears almost completely in both the thermal axion and massive sterile neutrino schemes. Extra light species contribute to the effective number of relativistic degrees of freedom, parametrized via N-eff. We found that when the recent detection of B mode polarization from the BICEP2 experiment is considered, an analysis of the combined CMB data in the framework of LCDM + r models gives N-eff = 3.90 +/- 0.42, suggesting the presence of an extra relativistic relic at more than 95% C.L. from CMB-only data.
Address [Giusarma, Elena; Di Valentino, Eleonora; Melchiorri, Alessandro] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000347985100004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2075
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Author Di Valentino, E.; Melchiorri, A.; Mena, O.
Title Can interacting dark energy solve the H-0 tension? Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 96 Issue 4 Pages (down) 043503 - 11pp
Keywords
Abstract The answer is yes. We indeed find that interacting dark energy can alleviate the current tension on the value of the Hubble constant H-0 between the cosmic microwave background anisotropies constraints obtained from the Planck satellite and the recent direct measurements reported by Riess et al. 2016. The combination of these two data sets points toward a nonzero dark matter-dark energy coupling. at more than two standard deviations, with xi = -0.26(-0.12)(+0.16) at 95% C.L., i.e. with a moderate evidence for interacting dark energy with an odds ratio of 6:1 respect to a non interacting cosmological constant. However the H-0 tension is better solved when the equation of state of the interacting dark energy component is allowed to freely vary, with a phantomlike equation of state w = -1.185 +/- 0.064 (at 68% C.L.), ruling out the pure cosmological constant case, w = -1, again at more than two standard deviations. When Planck data are combined with external datasets, as BAO, JLA Supernovae Ia luminosity distances, cosmic shear or lensing data, we find perfect consistency with the cosmological constant scenario and no compelling evidence for a dark matter-dark energy coupling.
Address [Di Valentino, Eleonora] CNRS, Inst Astrophys Paris, UMR7095, F-75014 Paris, France, Email: eleonora.di_valentino@iap.fr;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000427529900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3517
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Author Martinelli, M.; Melchiorri, A.; Mena, O.; Salvatelli, V.; Girones, Z.
Title Future constraints on the Hu-Sawicki modified gravity scenario Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 2 Pages (down) 024006 - 7pp
Keywords
Abstract We present current and future constraints on the Hu and Sawicki modified gravity scenario. This model can reproduce a late time accelerated universe and evade Solar System constraints. While current cosmological data still allows for distinctive deviations from the cosmological constant picture, future measurements of the growth of structure combined with supernova Ia luminosity distance data will greatly improve present constraints.
Address [Martinelli, Matteo; Melchiorri, Alessandro; Salvatelli, Valentina] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000298990200005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 870
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Author Castorina, E.; Franca, U.; Lattanzi, M.; Lesgourgues, J.; Mangano, G.; Melchiorri, A.; Pastor, S.
Title Cosmological lepton asymmetry with a nonzero mixing angle theta(13) Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 86 Issue 2 Pages (down) 023517 - 11pp
Keywords
Abstract While the baryon asymmetry of the Universe is nowadays well measured by cosmological observations, the bounds on the lepton asymmetry in the form of neutrinos are still significantly weaker. We place limits on the relic neutrino asymmetries using some of the latest cosmological data, taking into account the effect of flavor oscillations. We present our results for two different values of the neutrino mixing angle theta(13), and show that for large theta(13) the limits on the total neutrino asymmetry become more stringent, diluting even large initial flavor asymmetries. In particular, we find that the present bounds are still dominated by the limits coming from big bang nucleosynthesis, while the limits on the total neutrino mass from cosmological data are essentially independent of theta(13). Finally, we perform a forecast for Cosmic Origins Explorer, taken as an example of a future cosmic microwave background experiment, and find that it could improve the limits on the total lepton asymmetry approximately by up to a factor 6.6.
Address [Castorina, Emanuele] SISSA, I-34136 Trieste, Italy
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000306320000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1093
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Author De Bernardis, F.; Martinelli, M.; Melchiorri, A.; Mena, O.; Cooray, A.
Title Future weak lensing constraints in a dark coupled universe Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 2 Pages (down) 023504 - 10pp
Keywords
Abstract Probing the dark matter clustering and its evolution with weak lensing surveys constitutes a unique tool to constrain interacting dark energy models. We focus here on weak lensing forecasts from future Euclid and LSST-like surveys combined with the expected results from the ongoing Planck cosmic microwave background satellite experiment. We find that these future data could constrain the dimensionless coupling between dark matter and dark energy to be smaller than a few x 10(-2), improving the CMB-only constraint by at least 2 orders of magnitude. We also show that coupled cosmologies can substantially alter the constraints on cosmological parameters obtained from CMB experiments under the assumption of noninteracting cosmologies unless weak lensing data is considered.
Address [De Bernardis, F; Cooray, A] Univ Calif Irvine, Dept Phys & Astron, Irvine, CA 92697 USA
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000292515000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 681
Permanent link to this record