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Author |
Di Valentino, E.; Gariazzo, S.; Mena, O.; Vagnozzi, S. |
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Title |
Soundness of dark energy properties |
Type |
Journal Article |
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Year |
2020 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages  |
045 - 45pp |
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Keywords |
supernova type Ia – standard candles; dark energy experiments; cosmological parameters from CMBR; cosmological parameters from LSS |
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Abstract |
Type Ia Supernovae (SNeIa) used as standardizable candles have been instrumental in the discovery of cosmic acceleration, usually attributed to some form of dark energy (DE). Recent studies have raised the issue of whether intrinsic SNeIa luminosities might evolve with redshift. While the evidence for cosmic acceleration is robust to this possible systematic, the question remains of how much the latter can affect the inferred properties of the DE component responsible for cosmic acceleration. This is the question we address in this work. We use SNeIa distance moduli measurements from the Pantheon and JLA samples. We consider models where the DE equation of state is a free parameter, either constant or time-varying, as well as models where DE and dark matter interact, and finally a model-agnostic parametrization of effects due to modified gravity (MG). When SNeIa data are combined with Cosmic Microwave Background (CMB) temperature and polarization anisotropy measurements, we find strong degeneracies between parameters governing the SNeIa systematics, the DE parameters, and the Hubble constant H-0. These degeneracies significantly broaden the DE parameter uncertainties, in some cases leading to O(sigma) shifts in the central values. However, including low-redshift Baryon Acoustic Oscillation and Cosmic Chronometer measurements, as well as CMB lensing measurements, considerably improves the previous constraints, and the only remaining effect of the examined systematic is a less than or similar to 40% broadening of the uncertainties on the DE parameters. The constraints we derive on the MG parameters are instead basically unaffected by the systematic in question. We therefore confirm the overall soundness of dark energy properties. |
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Address |
[Di Valentino, Eleonora] Univ Manchester, Sch Phys & Astron, Jodrell Bank Ctr Astrophys, Oxford Rd, Manchester M13 9PL, Lancs, England, Email: eleonora.divalentino@mancher.ac.uk; |
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Publisher |
Iop Publishing Ltd |
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English |
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ISSN |
1475-7516 |
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Notes |
WOS:000551883400049 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4475 |
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Author |
Zhai, Y.J.; Giare, W.; van de Bruck, C.; Di Valentino, E.; Mena, O.; Nunes, R.C. |
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Title |
A consistent view of interacting dark energy from multiple CMB probes |
Type |
Journal Article |
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Year |
2023 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages |
032 - 16pp |
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Keywords |
cosmological parameters from CMBR; dark energy theory |
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Abstract |
We analyze a cosmological model featuring an interaction between dark energy and dark matter in light of the measurements of the Cosmic Microwave Background released by three independent experiments: the most recent data by the Planck satellite and the Atacama Cosmology Telescope, and WMAP (9-year data). We show that different combinations of the datasets provide similar results, always favoring an interacting dark sector with a 95% C.L. significance in the majority of the cases. Remarkably, such a preference remains consistent when cross-checked through independent probes, while always yielding a value of the expansion rate H0 consistent with the local distance ladder measurements. We investigate the source of this preference by scrutinizing the angular power spectra of temperature and polarization anisotropies as measured by different experiments. |
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Address |
[Zhai, Yuejia; Giare, William; van de Bruck, Carsten; Di Valentino, Eleonora] Univ Sheffield, Sch Math & Stat, Hounsfield Rd, Sheffield S3 7RH, England, Email: yzhai13@sheffield.ac.uk; |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Language |
English |
Summary Language |
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Abbreviated Series Title |
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Series Volume |
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ISSN |
1475-7516 |
ISBN |
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Conference |
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Notes |
WOS:001066525900001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5673 |
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Author |
Di Valentino, E.; Melchiorri, A.; Mena, O.; Pan, S.; Yang, W.Q. |
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Title |
Interacting dark energy in a closed universe |
Type |
Journal Article |
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Year |
2021 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
502 |
Issue |
1 |
Pages |
L23-L28 |
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Keywords |
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Abstract |
Recent measurements of the Cosmic Microwave Anisotropies power spectra measured by the Planck satellite show a preference for a closed universe at more than 99 per cent confidence level (CL). Such a scenario is however in disagreement with several low redshift observables, including luminosity distances of Type Ia supernovae. Here we show that interacting dark energy (IDE) models can ease the discrepancies between Planck and supernovae Ia data in a closed Universe, leading to a preference for both a coupling and a curvature different from zero above the 99 per cent CL. Therefore IDE cosmologies remain as very appealing scenarios, as they can provide the solution to a number of observational tensions in different fiducial cosmologies. The results presented here strongly favour broader analyses of cosmological data, and suggest that relaxing the usual flatness and vacuum energy assumptions can lead to a much better agreement among theory and observations. |
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Series Volume |
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ISSN |
0035-8711 |
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Conference |
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Notes |
WOS:000662142100005 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4879 |
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Author |
Di Valentino, E.; Mena, O. |
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Title |
A fake interacting dark energy detection? |
Type |
Journal Article |
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Year |
2021 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
500 |
Issue |
1 |
Pages |
L22-L26 |
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Keywords |
cosmic background radiation; cosmological parameters; dark energy |
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Abstract |
Models involving an interaction between the dark matter and the dark energy sectors have been proposed to alleviate the long-standing Hubble constant tension. In this paper, we analyse whether the constraints and potential hints obtained for these interacting models remain unchanged when using simulated Planck data. Interestingly, our simulations indicate that a dangerous fake detection for a non-zero interaction among the dark matter and the dark energy fluids could arise when dealing with current cosmic microwave background (CMB) Planck measurements alone. The very same hypothesis is tested against future CMB observations, finding that only cosmic variance limited polarization experiments, such as PICO or PRISM, could be able to break the existing parameter degeneracies and provide reliable cosmological constraints. This paper underlines the extreme importance of confronting the results arising from data analyses with those obtained with simulations when extracting cosmological limits within exotic cosmological scenarios. |
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Address |
[Di Valentino, Eleonora] Univ Manchester, Jodrell Bank Ctr Astrophys, Sch Phys & Astron, Oxford Rd, Manchester M13 9PL, Lancs, England, Email: eleonora.divalentino@manchester.ac.uk |
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Publisher |
Oxford Univ Press |
Place of Publication |
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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 |
0035-8711 |
ISBN |
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Conference |
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Notes |
WOS:000599143200006 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4665 |
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Author |
D'Eramo, F.; Di Valentino, E.; Giare, W.; Hajkarim, F.; Melchiorri, A.; Mena, O.; Renzi, F.; Yun, S. |
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Title |
Cosmological bound on the QCD axion mass, redux |
Type |
Journal Article |
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Year |
2022 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
09 |
Issue |
9 |
Pages |
022 - 35pp |
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Keywords |
axions; cosmology of theories beyond the SM; cosmological neutrinos; neutrino masses from cosmology |
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Abstract |
We revisit the joint constraints in the mixed hot dark matter scenario in which both thermally produced QCD axions and relic neutrinos are present. Upon recomputing the cosmological axion abundance via recent advances in the literature, we improve the state-of-the-art analyses and provide updated bounds on axion and neutrino masses. By avoiding approximate methods, such as the instantaneous decoupling approximation, and limitations due to the limited validity of the perturbative approach in QCD that forced to artificially divide the constraints from the axion-pion and the axion-gluon production channels, we find robust and self-consistent limits. We investigate the two most popular axion frameworks: KSVZ and DFSZ. From Big Bang Nucleosynthesis (BBN) light element abundances data we find for the KSVZ axion Delta N-eff < 0.31 and an axion mass bound m(a) < 0.53 eV (i.e., a bound on the axion decay constant f(a) > 1.07 x 10(7) GeV) both at 95% CL. These BBN bounds are improved to Delta N-eff < 0.14 and m(a) < 0.16 eV (f(a) > 3.56 x 10(7) GeV) if a prior on the baryon energy density from Cosmic Microwave Background (CMB) data is assumed. When instead considering cosmological observations from the CMB temperature, polarization and lensing from the Planck satellite combined with large scale structure data we find Delta N-eff < 0.23, m(a) < 0.28 eV (f(a) > 2.02 x 10(7) GeV) and Sigma m(nu) < 0.16 eV at 95% CL. This corresponds approximately to a factor of 5 improvement in the axion mass bound with respect to the existing limits. Very similar results are obtained for the DFSZ axion. We also forecast upcoming observations from future CMB and galaxy surveys, showing that they could reach percent level errors for m(a) similar to 1 eV. |
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Address |
[D'Eramo, Francesco; Hajkarim, Fazlollah; Yun, Seokhoon] Univ Padua, Dipartimento Fis & Astron, Via Marzolo 8, I-35131 Padua, Italy, Email: francesco.deramo@pd.infn.it; |
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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 |
WOS:000863296000010 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5383 |
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| Permanent link to this record |
