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Author |
Archidiacono, M.; Giusarma, E.; Hannestad, S.; Mena, O. |
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Title |
Cosmic Dark Radiation and Neutrinos |
Type |
Journal Article |
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Year |
2013 |
Publication |
Advances in High Energy Physics |
Abbreviated Journal |
Adv. High. Energy Phys. |
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Volume |
2013 |
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Pages |
191047 - 14pp |
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Abstract |
New measurements of the cosmic microwave background (CMB) by the Planck mission have greatly increased our knowledge about the universe. Dark radiation, a weakly interacting component of radiation, is one of the important ingredients in our cosmological model which is testable by Planck and other observational probes. At the moment, the possible existence of dark radiation is an unsolved question. For instance, the discrepancy between the value of the Hubble constant, H-0, inferred from the Planck data and local measurements of H-0 can to some extent be alleviated by enlarging the minimal ACDM model to include additional relativistic degrees of freedom. From a fundamental physics point of view, dark radiation is no less interesting. Indeed, it could well be one of the most accessible windows to physics beyond the standard model, for example, sterile neutrinos. Here, we review the most recent cosmological results including a complete investigation of the dark radiation sector in order to provide an overview of models that are still compatible with new cosmological observations. Furthermore, we update the cosmological constraints on neutrino physics and dark radiation properties focusing on tensions between data sets and degeneracies among parameters that can degrade our information or mimic the existence of extra species. |
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Address |
[Archidiacono, Maria; Hannestad, Steen] Univ Aarhus, Dept Phys & Astron, DK-8000 Aarhus C, Denmark, Email: archi@phys.au.dk |
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Publisher |
Hindawi Publishing Corporation |
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Language |
English |
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Edition |
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ISSN |
1687-7357 |
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Notes |
WOS:000327959400001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1660 |
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Author |
Diamanti, R.; Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C. |
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Title |
Constraining dark matter late-time energy injection: decays and p-wave annihilations |
Type |
Journal Article |
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Year |
2014 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
02 |
Issue |
2 |
Pages |
017 - 24pp |
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Keywords |
dark matter theory; CMBR theory |
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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. |
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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; |
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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:000332711400017 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1732 |
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Author |
Anderson, L. et al; Mena, O. |
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Title |
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: measuring D-A and H at z=0.57 from the baryon acoustic peak in the Data Release 9 spectroscopic Galaxy sample |
Type |
Journal Article |
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Year |
2014 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
439 |
Issue |
1 |
Pages |
83-101 |
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Keywords |
cosmological parameters; cosmology: observations; dark energy; distance scale; large scale structure of Universe |
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Abstract |
We present measurements of the angular diameter distance to and Hubble parameter at z = 0.57 from the measurement of the baryon acoustic peak in the correlation of galaxies from the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey. Our analysis is based on a sample from Data Release 9 of 264 283 galaxies over 3275 square degrees in the redshift range 0.43 < z < 0.70. We use two different methods to provide robust measurement of the acoustic peak position across and along the line of sight in order to measure the cosmological distance scale. We find D-A(0.57) = 1408 +/- 45 Mpc and H(0.57) = 92.9 +/- 7.8 km s(-1) Mpc(-1) for our fiducial value of the sound horizon. These results from the anisotropic fitting are fully consistent with the analysis of the spherically averaged acoustic peak position presented in Anderson et al. Our distance measurements are a close match to the predictions of the standard cosmological model featuring a cosmological constant and zero spatial curvature. |
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Address |
[Anderson, Lauren] Univ Washington, Dept Astron, Seattle, WA 98195 USA, Email: djschlegel@lbl.gov |
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Publisher |
Oxford Univ Press |
Place of Publication |
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Language |
English |
Summary Language |
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Series Volume |
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ISSN |
0035-8711 |
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Expedition |
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Conference |
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Notes |
WOS:000333297700026 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1738 |
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Author |
Adey, D. et al; Cervera-Villanueva, A.; Donini, A.; Ghosh, T.; Gomez-Cadenas, J.J.; Hernandez, P.; Izmaylov, A.; Laing, A.; Mena, O.; Sorel, M.; Stamoulis, P. |
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Title |
Light sterile neutrino sensitivity at the nuSTORM facility |
Type |
Journal Article |
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Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
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Volume |
89 |
Issue |
7 |
Pages |
071301 - 7pp |
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Abstract |
A facility that can deliver beams of electron and muon neutrinos from the decay of a stored muon beam has the potential to unambiguously resolve the issue of the evidence for light sterile neutrinos that arises in short-baseline neutrino oscillation experiments and from estimates of the effective number of neutrino flavors from fits to cosmological data. In this paper, we show that the nuSTORM facility, with stored muons of 3.8 GeV/c +/- 10%, will be able to carry out a conclusive muon neutrino appearance search for sterile neutrinos and test the LSND and MiniBooNE experimental signals with 10 sigma sensitivity, even assuming conservative estimates for the systematic uncertainties. This experiment would add greatly to our knowledge of the contribution of light sterile neutrinos to the number of effective neutrino flavors from the abundance of primordial helium production and from constraints on neutrino energy density from the cosmic microwave background. The appearance search is complemented by a simultaneous muon neutrino disappearance analysis that will facilitate tests of various sterile neutrino models. |
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Address |
[Adey, D.; Brice, S. J.; Bross, A. D.; Cease, H.; Geelhoed, M.; Kobilarcik, T.; Liu, A.; Mokhov, N.; Morfin, J.; Neuffer, D.; Palmer, M. A.; Parke, S.; Plunkett, R.; Popovic, M.; Rubinov, P.; Sen, T.; Snopok, P.; Striganov, S.] Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA, Email: Ryan.Bayes@glasgow.ac.uk |
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Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
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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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
1550-7998 |
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Conference |
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Notes |
WOS:000334317200002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1753 |
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Permanent link to this record |
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Author |
Anderson, L. et al; Mena, O. |
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Title |
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: baryon acoustic oscillations in the Data Releases 10 and 11 Galaxy samples |
Type |
Journal Article |
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Year |
2014 |
Publication |
Monthly Notices of the Royal Astronomical Society |
Abbreviated Journal |
Mon. Not. Roy. Astron. Soc. |
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Volume |
441 |
Issue |
1 |
Pages |
24-62 |
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Keywords |
cosmological parameters; cosmology: observations; dark energy; distance scale; large-scale structure of Universe |
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Abstract |
We present a one per cent measurement of the cosmic distance scale from the detections of the baryon acoustic oscillations (BAO) in the clustering of galaxies from the Baryon Oscillation Spectroscopic Survey, which is part of the Sloan Digital Sky Survey III. Our results come from the Data Release 11 (DR11) sample, containing nearly one million galaxies and covering approximately 8500 square degrees and the redshift range 0.2 < z < 0.7. We also compare these results with those from the publicly released DR9 and DR10 samples. Assuming a concordance A cold dark matter (ACDM) cosmological model, the DR11 sample covers a volume of 13 Gpc(3) and is the largest region of the Universe ever surveyed at this density. We measure the correlation function and power spectrum, including density- field reconstruction of the BAO feature. The acoustic features are detected at a significance of over 7s in both the correlation function and power spectrum. Fitting for the position of the acoustic features measures the distance relative to the sound horizon at the drag epoch, r(d), which has a value of r(d,fid) = 149.28 Mpc in our fiducial cosmology. We find D-V = (1264 +/- 25 Mpc)(r(d)/r(d,fid)) at z = 0.32 and D-V = (2056 +/- 20 Mpc)(r(d)/r(d,fid)) at z = 0.57. At 1.0 per cent, this latter measure is the most precise distance constraint ever obtained from a galaxy survey. Separating the clustering along and transverse to the line of sight yields measurements at z = 0.57 of D-A = (1421 +/- 20 Mpc)(r(d)/r(d,fid)) and H = (96.8 +/- 3.4 kms(-1) Mpc(-1))(r(d),(fid)/r(d)). Our measurements of the distance scale are in good agreement with previous BAO measurements and with the predictions from cosmic microwave background data for a spatially flat CDM model with a cosmological constant. |
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Address |
[Anderson, Lauren; Bhardwaj, Vaishali] Univ Washington, Dept Astron, Seattle, WA 98195 USA, Email: djschlegel@lbl.gov; |
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Corporate Author |
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Thesis |
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Publisher |
Oxford Univ Press |
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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ISSN |
0035-8711 |
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Notes |
WOS:000336249300002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1791 |
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Permanent link to this record |