Records |
Author |
Lopez-Honorez, L.; Mena, O.; Rigolin, S. |
Title |
Biases on cosmological parameters by general relativity effects |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
85 |
Issue |
2 |
Pages |
023511 - 12pp |
Keywords |
|
Abstract |
General relativistic corrections to the galaxy power spectrum appearing at the horizon scale, if neglected, may induce biases on the measured values of the cosmological parameters. In this paper, we study the impact of general relativistic effects on non standard cosmologies such as scenarios with a time dependent dark energy equation of state, with a coupling between the dark energy and the dark matter fluids or with non-Gaussianities. We then explore whether general relativistic corrections affect future constraints on cosmological parameters in the case of a constant dark energy equation of state and of non-Gaussianities. We find that relativistic corrections on the power spectrum are not expected to affect the foreseen errors on the cosmological parameters nor to induce large biases on them. |
Address |
[Lopez-Honorez, L.] Univ Libre Bruxelles, Serv Phys Theor, Brussels, Belgium |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
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 |
1550-7998 |
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:000298990300004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
867 |
Permanent link to this record |
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Author |
Salvatelli, V.; Marchini, A.; Lopez-Honorez, L.; Mena, O. |
Title |
New constraints on coupled dark energy from the Planck satellite experiment |
Type |
Journal Article |
Year |
2013 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
88 |
Issue |
2 |
Pages |
023531 - 9pp |
Keywords |
|
Abstract |
We present new constraints on coupled dark energy from the recent measurements of the cosmic microwave background anisotropies from the Planck satellite mission. We found that a coupled dark energy model is fully compatible with the Planck measurements, deriving a weak bound on the dark matter-dark energy coupling parameter xi = -0.49(-0.31)(+0.19) at 68% C.L. Moreover if Planck data are fitted to a coupled dark energy scenario, the constraint on the Hubble constant is relaxed to H-0 = 72.1(-2.3)(+3.2) km/s/Mpc, solving the tension with the Hubble Space Telescope (HST) value. We show that a combined PLANCK + HST analysis provides significant evidence for coupled dark energy finding a nonzero value for the coupling parameter xi, with -0.90 < xi < -0.22 at 95% C.L. We also consider the combined constraints from the Planck data plus the baryon acoustic oscillation measurements of the 6dF Galaxy Survey, the Sloan Digital Sky Survey and the Baron Oscillation Spectroscopic Survey. |
Address |
[Salvatelli, Valentina; Marchini, Andrea] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
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 |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000322216900003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1524 |
Permanent link to this record |
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Author |
Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. |
Title |
Constraints on dark matter annihilation from CMB observations before Planck |
Type |
Journal Article |
Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
07 |
Issue |
7 |
Pages |
046 - 26pp |
Keywords |
dark matter theory; CMBR theory |
Abstract |
We compute the bounds on the dark matter (DM) annihilation cross section using the most recent Cosmic Microwave Background measurements from WMAP9, SPT'11 and ACT'10. We consider DM with mass in the MeV-TeV range annihilating 100% into either an e(+)e(-) or a mu(+)mu(-) pair. We consider a realistic energy deposition model, which includes the dependence on the redshift, DM mass and annihilation channel. We exclude the canonical thermal relic abundance cross section (<sigma nu > = 3 x 10(-26) cm(3)s(-1)) for DM masses below 30 GeV and 15 GeV for the e(+)e(-) and mu(+)mu(-) channels, respectively. A priori, DM annihilating in halos could also modify the reionization history of the Universe at late times. We implement a realistic halo model taken from results of state-of-the-art N-body simulations and consider a mixed reionization mechanism, consisting on reionization from DM as well as from first stars. We find that the constraints on DM annihilation remain unchanged, even when large uncertainties on the halo model parameters are considered. |
Address |
[Lopez-Honorez, Laura] Vrije Univ Brussel, B-1050 Brussels, Belgium, Email: llopezho@vub.ac.be; |
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:000322582000047 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1533 |
Permanent link to this record |
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Author |
Diamanti, R.; Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. |
Title |
Constraining dark matter late-time energy injection: decays and p-wave annihilations |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
02 |
Issue |
2 |
Pages |
017 - 24pp |
Keywords |
dark matter theory; CMBR theory |
Abstract |
We use the latest cosmic microwave background (CMB) observations to provide updated constraints on the dark matter lifetime as well as on p-wave suppressed annihilation cross sections in the 1 MeV to 1 TeV mass range. In contrast to scenarios with an s-wave dominated annihilation cross section, which mainly affect the CMB close to the last scattering surface, signatures associated with these scenarios essentially appear at low redshifts (z less than or similar to 50) when structure began to form, and thus manifest at lower multipoles in the CMB power spectrum. We use data from Planck, WMAP9, SPT and ACT, as well as Lyman-alpha measurements of the matter temperature at z similar to 4 to set a 95% confidence level lower bound on the dark matter lifetime of similar to 4 x 10(25) s for m(chi) = 100 MeV. This bound becomes lower by an order of magnitude at m(chi) = 1 TeV due to inefficient energy deposition into the inter-galactic medium. We also show that structure formation can enhance the effect of p-wave suppressed annihilation cross sections by many orders of magnitude with respect to the background cosmological rate, although even with this enhancement, CMB constraints are not yet strong enough to reach the thermal relic value of the cross section. |
Address |
[Diamanti, Roberta; Mena, Olga; Palomares-Ruiz, Sergio; Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: R.Diamanti@uva.nl; |
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 |
|
Area |
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Expedition |
|
Conference |
|
Notes |
WOS:000332711400017 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1732 |
Permanent link to this record |
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Author |
Archidiacono, M.; Lopez-Honorez, L.; Mena, O. |
Title |
Current constraints on early and stressed dark energy models and future 21 cm perspectives |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
90 |
Issue |
12 |
Pages |
123016 - 10pp |
Keywords |
|
Abstract |
Despite the great progress of current cosmological measurements, the nature of the dominant component of the Universe, coined dark energy, is still an open question. Early dark energy is a possible candidate which may also alleviate some fine-tuning issues of the standard paradigm. Using the latest available cosmological data, we find that the 95% C.L. upper bound on the early dark energy density parameter is Tau(eDE) < 0.009. On the other hand, the dark energy component may be a stressed and inhomogeneous fluid. If this is the case, the effective sound speed and the viscosity parameters are unconstrained by current data. Future omniscopelike 21 cm surveys, combined with present cosmic microwave background data, could be able to distinguish between standard quintessence scenarios from other possible models with 2 sigma significance, assuming a non-negligible early dark energy contribution. The precision achieved on the Omega(eDE) parameter from these 21 cm probes could be below O(10%). |
Address |
[Archidiacono, Maria] Aarhus Univ, Dept Phys & Astron, DK-8000 Aarhus C, Denmark |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
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 |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000347194400007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2066 |
Permanent link to this record |