We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and a recent reanalysis of Type Ia supernova (SN) data. In particular, we take advantage of high-precision BAO measurements from galaxy clustering and the Lyman-alpha forest (LyaF) in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Treating the BAO scale as an uncalibrated standard ruler, BAO data alone yield a high confidence detection of dark energy; in combination with the CMB angular acoustic scale they further imply a nearly flat universe. Adding the CMB-calibrated physical scale of the sound horizon, the combination of BAO and SN data into an "inverse distance ladder" yields a measurement of H-0 = 67.3 +/- 1.1 km s(-1) Mpc(-1), with 1.7% precision. This measurement assumes standard prerecombination physics but is insensitive to assumptions about dark energy or space curvature, so agreement with CMB-based estimates that assume a flat Lambda CDM cosmology is an important corroboration of this minimal cosmological model. For constant dark energy (Lambda), our BAO + SN + CMB combination yields matter density Omega(m) = 0.301 +/- 0.008 and curvature Omega(k) = -0.003 +/- 0.003. When we allow more general forms of evolving dark energy, the BAO + SN + CMB parameter constraints are always consistent with flat Lambda CDM values at approximate to 1 sigma. While the overall chi(2) of model fits is satisfactory, the LyaF BAO measurements are in moderate (2-2.5 sigma) tension with model predictions. Models with early dark energy that tracks the dominant energy component at high redshift remain consistent with our expansion history constraints, and they yield a higher H-0 and lower matter clustering amplitude, improving agreement with some low redshift observations. Expansion history alone yields an upper limit on the summed mass of neutrino species, Sigma m(nu) < 0.56 eV (95% confidence), improving to Sigma m(nu) < 0.25 eV if we include the lensing signal in the Planck CMB power spectrum. In a flat Lambda CDM model that allows extra relativistic species, our data combination yields N-eff = 3.43 +/- 0.26; while the LyaF BAO data prefer higher N-eff when excluding galaxy BAO, the galaxy BAO alone favor N-eff approximate to 3. When structure growth is extrapolated forward from the CMB to low redshift, standard dark energy models constrained by our data predict a level of matter clustering that is high compared to most, but not all, observational estimates.
Cosmological implications of baryon acoustic oscillation measurements / Aubourg, É.; Bailey, S.; Bautista, J. E.; Beutler, F.; Bhardwaj, V.; Bizyaev, D.; Blanton, M.; Blomqvist, M.; Bolton, A. S.; Bovy, J.; Brewington, H.; Brinkmann, J.; Brownstein, J. R.; Burden, A.; Busca, N. G.; Carithers, W.; Chuang, C. H.; Comparat, J.; Croft, R. A. C.; Cuesta, A. J.; Dawson, K. S.; Delubac, T.; Eisenstein, D. J.; Font Ribera, A.; Ge, J.; Le Goff, J. M.; Gontcho, S. G. A.; Gott, J. R.; Iii, Gunn; Guo, H.; Guy, J.; Hamilton, J. C.; Ho, S.; Honscheid, K.; Howlett, C.; Kirkby, D.; Kitaura, Francisco Shu; Kneib, J. P.; Lee, K. G.; Long, D.; Lupton, R. H.; Magaña, M. V.; Malanushenko, V.; Malanushenko, E.; Manera, M.; Maraston, C.; Margala, D.; Mcbride, C. K.; Miralda Escudé, J.; Myers, A. D.; Nichol, R. C.; Noterdaeme, P.; Nuza, S. E.; Olmstead, M. D.; Oravetz, D.; Pâris, I.; Padmanabhan, N.; Palanque Delabrouille, N.; Pan, K.; Pellejero Ibanez, M.; Percival, W. J.; Petitjean, P.; Pieri, M. M.; Prada, F.; Reid, B.; Rich, J.; Roe, N. A.; Ross, A. J.; Ross, N. P.; Rossi, G.; Rubiño Martín, J. A.; Sánchez, A. G.; Samushia, L.; Santos, R. T. G.; Scóccola, C. G.; Schlegel, D. J.; Schneider, D. P.; Seo, H. J.; Sheldon, E.; Simmons, A.; Skibba, R. A.; Slosar, A.; Strauss, M. A.; Thomas, D.; Tinker, J. L.; Tojeiro, R.; Vazquez, J. A.; Viel, Matteo; Wake, D. A.; Weaver, B. A.; Weinberg, D. H.; Wood Vasey, W. M.; Yèche, C.; Zehavi, I.; Zhao, G. B.. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - 92:12(2015), pp. 1-38. [10.1103/PhysRevD.92.123516]
Cosmological implications of baryon acoustic oscillation measurements
Kitaura, Francisco Shu;Viel, Matteo;
2015-01-01
Abstract
We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and a recent reanalysis of Type Ia supernova (SN) data. In particular, we take advantage of high-precision BAO measurements from galaxy clustering and the Lyman-alpha forest (LyaF) in the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). Treating the BAO scale as an uncalibrated standard ruler, BAO data alone yield a high confidence detection of dark energy; in combination with the CMB angular acoustic scale they further imply a nearly flat universe. Adding the CMB-calibrated physical scale of the sound horizon, the combination of BAO and SN data into an "inverse distance ladder" yields a measurement of H-0 = 67.3 +/- 1.1 km s(-1) Mpc(-1), with 1.7% precision. This measurement assumes standard prerecombination physics but is insensitive to assumptions about dark energy or space curvature, so agreement with CMB-based estimates that assume a flat Lambda CDM cosmology is an important corroboration of this minimal cosmological model. For constant dark energy (Lambda), our BAO + SN + CMB combination yields matter density Omega(m) = 0.301 +/- 0.008 and curvature Omega(k) = -0.003 +/- 0.003. When we allow more general forms of evolving dark energy, the BAO + SN + CMB parameter constraints are always consistent with flat Lambda CDM values at approximate to 1 sigma. While the overall chi(2) of model fits is satisfactory, the LyaF BAO measurements are in moderate (2-2.5 sigma) tension with model predictions. Models with early dark energy that tracks the dominant energy component at high redshift remain consistent with our expansion history constraints, and they yield a higher H-0 and lower matter clustering amplitude, improving agreement with some low redshift observations. Expansion history alone yields an upper limit on the summed mass of neutrino species, Sigma m(nu) < 0.56 eV (95% confidence), improving to Sigma m(nu) < 0.25 eV if we include the lensing signal in the Planck CMB power spectrum. In a flat Lambda CDM model that allows extra relativistic species, our data combination yields N-eff = 3.43 +/- 0.26; while the LyaF BAO data prefer higher N-eff when excluding galaxy BAO, the galaxy BAO alone favor N-eff approximate to 3. When structure growth is extrapolated forward from the CMB to low redshift, standard dark energy models constrained by our data predict a level of matter clustering that is high compared to most, but not all, observational estimates.File | Dimensione | Formato | |
---|---|---|---|
PhysRevD.92.123516.pdf
non disponibili
Tipologia:
Versione Editoriale (PDF)
Licenza:
Non specificato
Dimensione
2.77 MB
Formato
Adobe PDF
|
2.77 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.