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Author Vagnozzi, S.; Di Valentino, E.; Gariazzo, S.; Melchiorri, A.; Mena, O.; Silk, J.
Title The galaxy power spectrum take on spatial curvature and cosmic concordance Type Journal Article
Year 2021 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 33 Issue Pages (up) 100851 - 17pp
Keywords Cosmological parameters; Spatial curvature; Cosmological tensions
Abstract The concordance of the ACDM cosmological model in light of current observations has been the subject of an intense debate in recent months. The 2018 Planck Cosmic Microwave Background (CMB) temperature anisotropy power spectrum measurements appear at face value to favour a spatially closed Universe with curvature parameter Omega(K) < 0. This preference disappears if Baryon Acoustic Oscillation (BAO) measurements are combined with Planck data to break the geometrical degeneracy, although the reliability of this combination has been questioned due to the strong tension present between the two datasets when assuming a curved Universe. Here, we approach this issue from yet another point of view, using measurements of the full-shape (FS) galaxy power spectrum, P(k), from the Baryon Oscillation Spectroscopic Survey DR12 CMASS sample. By combining Planck data with FS measurements, we break the geometrical degeneracy and find Omega(K) = 0.0023 +/- 0.0028. This constrains the Universe to be spatially flat to sub-percent precision, in excellent agreement with results obtained using BAO measurements. However, as with BAO, the overall increase in the best-fit chi(2) suggests a similar level of tension between Planck and P(k) under the assumption of a curved Universe. While the debate on spatial curvature and the concordance between cosmological datasets remains open, our results provide new perspectives on the issue, highlighting the crucial role of FS measurements in the era of precision cosmology.
Address [Vagnozzi, Sunny] Univ Cambridge, Kavli Inst Cosmol, Cambridge CB3 0HA, England, Email: sunny.vagnozzi@ast.cam.ac.uk;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000704383100022 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4984
Permanent link to this record
 
 
Author Gariazzo, S.; Mena, O.; Schwetz, T.
Title Quantifying the tension between cosmological and terrestrial constraints on neutrino masses Type Journal Article
Year 2023 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 40 Issue Pages (up) 101226 - 8pp
Keywords Neutrino masses; Neutrino mass ordering; Neutrino oscillations; Cosmological measurements of neutrino; masses
Abstract The sensitivity of cosmology to the total neutrino mass scale E m & nu; is approaching the minimal values required by oscillation data. We study quantitatively possible tensions between current and forecasted cosmological and terrestrial neutrino mass limits by applying suitable statistical tests such as Bayesian suspiciousness, parameter goodness-of-fit tests, or a parameter difference test. In particular, the tension will depend on whether the normal or the inverted neutrino mass ordering is assumed. We argue, that it makes sense to reject inverted ordering from the cosmology/oscillation comparison only if data are consistent with normal ordering. Our results indicate that, in order to reject inverted ordering with this argument, an accuracy on the sum of neutrino masses & sigma;(m & nu;) of better than 0.02 eV would be required from future cosmological observations.
Address [Gariazzo, Stefano] Ist Nazl Fis Nucl INFN, Sez Torino, Via P Giuria 1, I-10125 Turin, Italy, Email: gariazzo@to.infn.it
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001042929800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5623
Permanent link to this record
 
 
Author Gerbino, M. et al; Martinez-Mirave, P.; Mena, O.; Tortola, M.; Valle, J.W. .
Title Synergy between cosmological and laboratory searches in neutrino physics Type Journal Article
Year 2023 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 42 Issue Pages (up) 101333 - 36pp
Keywords Neutrinos; Cosmology; Neutrino phenomenology
Abstract The intersection of the cosmic and neutrino frontiers is a rich field where much discovery space still remains. Neutrinos play a pivotal role in the hot big bang cosmology, influencing the dynamics of the universe over numerous decades in cosmological history. Recent studies have made tremendous progress in understanding some properties of cosmological neutrinos, primarily their energy density. Upcoming cosmological probes will measure the energy density of relativistic particles with higher precision, but could also start probing other properties of the neutrino spectra. When convolved with results from terrestrial experiments, cosmology can become even more acute at probing new physics related to neutrinos or even Beyond the Standard Model (BSM). Any discordance between laboratory and cosmological data sets may reveal new BSM physics and/or suggest alternative models of cosmology. We give examples of the intersection between terrestrial and cosmological probes in the neutrino sector, and briefly discuss the possibilities of what different laboratory experiments may see in conjunction with cosmological observatories.
Address [Gerbino, Martina; Lattanzi, Massimiliano; Brinckmann, Thejs] INFN, Sez Ferrara, I-44122 Ferrara, Italy, Email: gerbinom@fe.infn.it;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001112368600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5854
Permanent link to this record
 
 
Author Ghedini, P.; Hajjar, R.; Mena, O.
Title Redshift-space distortions corner interacting dark energy Type Journal Article
Year 2024 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 46 Issue Pages (up) 101671 - 10pp
Keywords Dark energy; Dark matter; Dark sector interactions; Dark energy properties
Abstract Despite the fact that the Lambda CDM model has been highly successful over the last few decades in providing an accurate fit to a broad range of cosmological and astrophysical observations, different intriguing tensions and anomalies emerged at various statistical levels. Given the fact that the dark energy and the dark matter sectors remain unexplored, the answer to some of the tensions may rely on modifications of these two dark sectors. This manuscript explores the important role of the growth of structure in constraining non-standard cosmologies. In particular, we focus on the interacting dark energy (IDE) scenario, where dark matter and dark energy interact non-gravitationally. We aim to place constraints on the phenomenological parameters of these alternative models, by considering different datasets related to a number of cosmological measurements, to achieve a complementary analysis. A special emphasis is devoted to redshift-space distortion measurements (RSD), whose role in constraining beyond the standard paradigm models has not been recently highlighted. These observations indeed have a strong constraining power, rendering all parameters to their Lambda CDM canonical values, and therefore leaving little room for the IDE models explored here.
Address [Ghedini, Pietro] Univ Bologna, Dipartimento Fis & Astron, Via Irnerio 46, I-40126 Bologna, Italy, Email: pietro.ghedini3@studio.unibo.it;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001333958300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6298
Permanent link to this record
 
 
Author Di Valentino, E. et al; Mena, O.
Title Cosmology intertwined III: f sigma(8) and S-8 Type Journal Article
Year 2021 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 131 Issue Pages (up) 102604 - 6pp
Keywords cosmological tensions; cosmological parameters
Abstract The standard A Cold Dark Matter cosmological model provides a wonderful fit to current cosmological data, but a few statistically significant tensions and anomalies were found in the latest data analyses. While these anomalies could be due to the presence of systematic errors in the experiments, they could also indicate the need for new physics beyond the standard model. In this Letter of Interest we focus on the tension between Planck data and weak lensing measurements and redshift surveys, in the value of the matter energy density Omega(m), and the amplitude sigma(8) (or the growth rate f sigma(8)) of cosmic structure. We list a few promising models for solving this tension, and discuss the importance of trying to fit multiple cosmological datasets with complete physical models, rather than fitting individual datasets with a few handpicked theoretical parameters.
Address [Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000657813100006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4854
Permanent link to this record
 
 
Author Di Valentino, E. et al; Mena, O.
Title Snowmass2021-Letter of interest cosmology intertwined II: The hubble constant tension Type Journal Article
Year 2021 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 131 Issue Pages (up) 102605 - 8pp
Keywords
Abstract The current cosmological probes have provided a fantastic confirmation of the standard A Cold Dark Matter cosmological model, which has been constrained with unprecedented accuracy. However, with the increase of the experimental sensitivity, a few statistically significant tensions between different independent cosmological datasets emerged. While these tensions can be in part the result of systematic errors, the persistence after several years of accurate analysis strongly hints at cracks in the standard cosmological scenario and the need for new physics. In this Letter of Interest we will focus on the 4.4 sigma – tension between the Planck estimate of the Hubble constant H-0 and the SH0ES collaboration measurements. After showing the H-0 evaluations made from different teams using different methods and geometric calibrations, we will list a few interesting models of new physics that could solve this tension and discuss how the next decade's experiments will be crucial.
Address [Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000657813100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4853
Permanent link to this record
 
 
Author Di Valentino, E. et al; Mena, O.
Title Snowmass2021-Letter of interest cosmology intertwined I: Perspectives for the next decade Type Journal Article
Year 2021 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 131 Issue Pages (up) 102606 - 4pp
Keywords
Abstract The standard Lambda Cold Dark Matter cosmological model provides an amazing description of a wide range of astrophysical and astronomical data. However, there are a few big open questions, that make the standard model look like a first-order approximation to a more realistic scenario that still needs to be fully understood. In this Letter of Interest we will list a few important goals that need to be addressed in the next decade, also taking into account the current discordances present between the different cosmological probes, as the Hubble constant H-0 value, the sigma S-8(8) tension, and the anomalies present in the Planck results. Finally, we will give an overview of upgraded experiments and next-generation space-missions and facilities on Earth that will be of crucial importance to address all these questions.
Address [Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000657813100003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4856
Permanent link to this record
 
 
Author Di Valentino, E. et al; Mena, O.
Title Snowmass2021-Letter of interest cosmology intertwined IV: The age of the universe and its curvature Type Journal Article
Year 2021 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 131 Issue Pages (up) 102607 - 5pp
Keywords
Abstract A precise measurement of the curvature of the Universe is of prime importance for cosmology since it could not only confirm the paradigm of primordial inflation but also help in discriminating between different early-Universe scenarios. Recent observations, while broadly consistent with a spatially flat standard A Cold Dark Matter (ACDM) model, show tensions that still allow (and, in some cases, even suggest) a few percent deviations from a flat universe. In particular, the Planck Cosmic Microwave Background power spectra, assuming the nominal likelihood, prefer a closed universe at more than 99% confidence level. While new physics could be at play, this anomaly may be the result of an unresolved systematic error or just a statistical fluctuation. However, since positive curvature allows a larger age of the Universe, an accurate determination of the age of the oldest objects provides a smoking gun in confirming or falsifying the current flat ACDM model.
Address [Di Valentino, Eleonora; Chluba, Jens; Harrison, Ian; Hart, Luke; Pace, Francesco] Univ Manchester, JBCA, Manchester, Lancs, England, Email: eleonora.di-valentino@durham.ac.uk
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000657813100007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4855
Permanent link to this record
 
 
Author Boubekeur, L.; Giusarma, E.; Mena, O.; Ramirez, H.
Title Do current data prefer a nonminimally coupled inflaton? Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 91 Issue 10 Pages (up) 103004 - 6pp
Keywords
Abstract We examine the impact of a nonminimal coupling of the inflaton to the Ricci scalar, 1/2 xi R phi(2), on the inflationary predictions. Such a nonminimal coupling is expected to be present in the inflaton Lagrangian on fairly general grounds. As a case study, we focus on the simplest inflationary model governed by the potential V proportional to phi(2), using the latest combined 2015 analysis of Planck and the BICEP2/Keck Array. We find that the presence of a coupling xi is favored at a significance of 99% C.L., assuming that nature has chosen the potential V proportional to phi(2) to generate the primordial perturbations and a number of e-foldings N = 60. Within the context of the same scenario, we find that the value of xi is different from zero at the 2 sigma level. When considering the cross-correlation polarization spectra from the BICEP2/Keck Array and Planck, a value of r = 0.038(-0.030)(+0.039) is predicted in this particular nonminimally coupled scenario. Future cosmological observations may therefore test these values of r and verify or falsify the nonminimally coupled model explored here.
Address [Boubekeur, Lotfi; Mena, Olga; Ramirez, Hector] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain
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:000354979300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2237
Permanent link to this record
 
 
Author Palomares-Ruiz, S.; Vincent, A.C.; Mena, O.
Title Spectral analysis of the high-energy IceCube neutrinos Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 91 Issue 10 Pages (up) 103008 - 28pp
Keywords
Abstract A full energy and flavor-dependent analysis of the three-year high-energy IceCube neutrino events is presented. By means of multidimensional fits, we derive the current preferred values of the high-energy neutrino flavor ratios, the normalization and spectral index of the astrophysical fluxes, and the expected atmospheric background events, including a prompt component. A crucial assumption resides on the choice of the energy interval used for the analyses, which significantly biases the results. When restricting ourselves to the similar to 30 TeV-3 PeV energy range, which contains all the observed IceCube events, we find that the inclusion of the spectral information improves the fit to the canonical flavor composition at Earth, (1: 1: 1)(circle plus), with respect to a single-energy bin analysis. Increasing both the minimum and the maximum deposited energies has dramatic effects on the reconstructed flavor ratios as well as on the spectral index. Imposing a higher threshold of 60 TeV yields a slightly harder spectrum by allowing a larger muon neutrino component, since above this energy most atmospheric tracklike events are effectively removed. Extending the high-energy cutoff to fully cover the Glashow resonance region leads to a softer spectrum and a preference for tau neutrino dominance, as none of the expected electron (anti) neutrino induced showers have been observed so far. The lack of showers at energies above 2 PeV may point to a broken power-law neutrino spectrum. Future data may confirm or falsify whether the recently discovered high-energy neutrino fluxes and the long-standing detected cosmic rays have a common origin.
Address [Palomares-Ruiz, Sergio; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain
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:000355173100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2242
Permanent link to this record