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S. Nakayama

Bio: S. Nakayama is an academic researcher from University of Tokyo. The author has contributed to research in topics: Neutrino & Neutrino oscillation. The author has an hindex of 37, co-authored 64 publications receiving 14144 citations. Previous affiliations of S. Nakayama include National Research Nuclear University MEPhI & Rutherford Appleton Laboratory.


Papers
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Journal ArticleDOI
Y. Fukuda1, T. Hayakawa1, E. Ichihara1, Kunio Inoue1, K. Ishihara1, H. Ishino1, Yoshitaka Itow1, Takaaki Kajita1, J. Kameda1, S. Kasuga1, Ken-ichiro Kobayashi1, Yohei Kobayashi1, Yusuke Koshio1, M. Miura1, Masayuki Nakahata1, S. Nakayama1, A. Okada1, Ko Okumura1, N. Sakurai1, Masato Shiozawa1, Yoshihiro Suzuki1, Y. Takeuchi1, Y. Totsuka1, Shinya Yamada1, M. Earl2, Alec Habig2, E. Kearns2, M. D. Messier2, Kate Scholberg2, J. L. Stone2, Lawrence Sulak2, C. W. Walter2, M. Goldhaber3, T. Barszczxak4, D. Casper4, W. Gajewski4, P. G. Halverson4, J. Hsu4, W. R. Kropp4, L. R. Price4, Frederick Reines4, Michael B. Smy4, Henry W. Sobel4, Mark R. Vagins4, K. S. Ganezer5, W. E. Keig5, R. W. Ellsworth6, S. Tasaka7, J. W. Flanagan8, A. Kibayashi8, John G. Learned8, S. Matsuno8, V. J. Stenger8, D. Takemori8, T. Ishii, Junichi Kanzaki, T. Kobayashi, S. Mine, K. Nakamura, K. Nishikawa, Yuichi Oyama, A. Sakai, Makoto Sakuda, Osamu Sasaki, S. Echigo9, M. Kohama9, A. T. Suzuki9, Todd Haines4, Todd Haines10, E. Blaufuss11, B. K. Kim11, R. Sanford11, R. Svoboda11, M. L. Chen12, Z. Conner12, Z. Conner13, J. A. Goodman12, G. W. Sullivan12, J. Hill14, C. K. Jung14, K. Martens14, C. Mauger14, C. McGrew14, E. Sharkey14, B. Viren14, C. Yanagisawa14, W. Doki15, Kazumasa Miyano15, H. Okazawa15, C. Saji15, M. Takahata15, Y. Nagashima16, M. Takita16, Takashi Yamaguchi16, Minoru Yoshida16, Soo-Bong Kim17, M. Etoh18, K. Fujita18, Akira Hasegawa18, Takehisa Hasegawa18, S. Hatakeyama18, T. Iwamoto18, M. Koga18, Tomoyuki Maruyama18, Hiroshi Ogawa18, J. Shirai18, A. Suzuki18, F. Tsushima18, Masatoshi Koshiba1, M. Nemoto19, Kyoshi Nishijima19, T. Futagami20, Y. Hayato20, Y. Kanaya20, K. Kaneyuki20, Y. Watanabe20, D. Kielczewska4, D. Kielczewska21, R. A. Doyle22, J. S. George22, A. L. Stachyra22, L. Wai22, L. Wai23, R. J. Wilkes22, K. K. Young22 
Abstract: We present an analysis of atmospheric neutrino data from a 33.0 kton yr (535-day) exposure of the Super-Kamiokande detector. The data exhibit a zenith angle dependent deficit of muon neutrinos which is inconsistent with expectations based on calculations of the atmospheric neutrino flux. Experimental biases and uncertainties in the prediction of neutrino fluxes and cross sections are unable to explain our observation. The data are consistent, however, with two-flavor ${\ensuremath{ u}}_{\ensuremath{\mu}}\ensuremath{\leftrightarrow}{\ensuremath{ u}}_{\ensuremath{\tau}}$ oscillations with ${sin}^{2}2\ensuremath{\theta}g0.82$ and $5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}l\ensuremath{\Delta}{m}^{2}l6\ifmmode\times\else\texttimes\fi{}1{0}^{\ensuremath{-}3}\mathrm{eV}{}^{2}$ at 90% confidence level.

3,784 citations

Journal ArticleDOI
K. Abe1, N. Abgrall2, Yasuo Ajima, Hiroaki Aihara1  +413 moreInstitutions (53)
TL;DR: The T2K experiment observes indications of ν (μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target, and under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance.
Abstract: The T2K experiment observes indications of nu(mu) -> nu(mu) e appearance in data accumulated with 1.43 x 10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Delta m(23)(2)| = 2.4 x 10(-3) eV(2), sin(2)2 theta(23) = 1 and sin(2)2 theta(13) = 0, the expected number of such events is 1.5 +/- 0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7 x 10(-3), equivalent to 2.5 sigma significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2 theta(13) < 0.28(0.34) for delta(CP) = 0 and a normal (inverted) hierarchy.

1,361 citations

Journal ArticleDOI
Y. Fukuda1, M. Ishitsuka1, Yoshitaka Itow1, Takaaki Kajita1, J. Kameda1, K. Kaneyuki1, K. Kobayashi1, Yusuke Koshio1, M. Miura1, S. Moriyama1, Masayuki Nakahata1, S. Nakayama1, A. Okada1, N. Sakurai1, Masato Shiozawa1, Yoshihiro Suzuki1, H. Takeuchi1, Y. Takeuchi1, T. Toshito1, Y. Totsuka1, Shoichi Yamada1, Shantanu Desai2, M. Earl2, E. Kearns2, M. D. Messier2, Kate Scholberg2, Kate Scholberg3, J. L. Stone2, L. R. Sulak2, C. W. Walter2, M. Goldhaber4, T. Barszczak5, David William Casper5, W. Gajewski5, W. R. Kropp5, S. Mine5, D. W. Liu5, L. R. Price5, M. B. Smy5, Henry W. Sobel5, M. R. Vagins5, Todd Haines5, D. Kielczewska5, K. S. Ganezer6, W. E. Keig6, R. W. Ellsworth7, S. Tasaka8, A. Kibayashi, John G. Learned, S. Matsuno, D. Takemori, Y. Hayato, T. Ishii, Takashi Kobayashi, Koji Nakamura, Y. Obayashi, Y. Oyama, A. Sakai, Makoto Sakuda, M. Kohama9, Atsumu Suzuki9, T. Inagaki10, Tsuyoshi Nakaya10, K. Nishikawa10, E. Blaufuss11, S. Dazeley11, R. Svoboda11, J. A. Goodman12, G. Guillian12, G. W. Sullivan12, D. Turcan12, Alec Habig13, J. Hill14, C. K. Jung14, K. Martens15, K. Martens14, Magdalena Malek14, C. Mauger14, C. McGrew14, E. Sharkey14, B. Viren14, C. Yanagisawa14, C. Mitsuda16, K. Miyano16, C. Saji16, T. Shibata16, Y. Kajiyama17, Y. Nagashima17, K. Nitta17, M. Takita17, Minoru Yoshida17, Heekyong Kim18, Soo-Bong Kim18, J. Yoo18, H. Okazawa, T. Ishizuka19, M. Etoh20, Y. Gando20, Takehisa Hasegawa20, Kunio Inoue20, K. Ishihara20, Tomoyuki Maruyama20, J. Shirai20, A. Suzuki20, Masatoshi Koshiba1, Y. Hatakeyama21, Y. Ichikawa21, M. Koike21, Kyoshi Nishijima21, H. Fujiyasu22, Hirokazu Ishino22, M. Morii22, Y. Watanabe22, U. Golebiewska23, S. C. Boyd24, A. L. Stachyra24, R. J. Wilkes24, B. Lee 
TL;DR: Solar neutrino measurements from 1258 days of data from the Super-Kamiokande detector are presented and the recoil electron energy spectrum is consistent with no spectral distortion.
Abstract: Solar neutrino measurements from 1258days of data from the Super-Kamiokande detector are presented. The measurements are based on recoil electrons in the energy range 5.0{endash}20.0MeV. The measured solar neutrino flux is 2.32{+-}0.03(stat){sup +0.08}{sub {minus}0.07}(syst){times}10{sup 6} cm{sup {minus}2}s{sup {minus}1} , which is 45.1{+-}0.5(stat ){sup +1.6}{sub {minus}1.4}(syst) % of that predicted by the BP2000 SSM. The day vs night flux asymmetry ({Phi}{sub n}{minus}{Phi}{sub d})/ {Phi}{sub average} is 0.033{+-}0.022(stat){sup +0.013}{sub {minus}0.012}(syst) . The recoil electron energy spectrum is consistent with no spectral distortion. For the hep neutrino flux, we set a 90% C.L.upper limit of 40{times}10{sup 3} cm{sup {minus}2}s{sup {minus}1} , which is 4.3times the BP2000 SSM prediction.

878 citations

Journal ArticleDOI
K. Abe1, N. Abgrall2, Hiroaki Aihara1, Yasuo Ajima  +533 moreInstitutions (53)
TL;DR: The T2K experiment as discussed by the authors is a long-baseline neutrino oscillation experiment whose main goal is to measure the last unknown lepton sector mixing angle by observing its appearance in a particle beam generated by the J-PARC accelerator.
Abstract: The T2K experiment is a long-baseline neutrino oscillation experiment Its main goal is to measure the last unknown lepton sector mixing angle {\theta}_{13} by observing { u}_e appearance in a { u}_{\mu} beam It also aims to make a precision measurement of the known oscillation parameters, {\Delta}m^{2}_{23} and sin^{2} 2{\theta}_{23}, via { u}_{\mu} disappearance studies Other goals of the experiment include various neutrino cross section measurements and sterile neutrino searches The experiment uses an intense proton beam generated by the J-PARC accelerator in Tokai, Japan, and is composed of a neutrino beamline, a near detector complex (ND280), and a far detector (Super-Kamiokande) located 295 km away from J-PARC This paper provides a comprehensive review of the instrumentation aspect of the T2K experiment and a summary of the vital information for each subsystem

714 citations

Journal ArticleDOI
S. Fukuda1, Y. Fukuda1, T. Hayakawa1, E. Ichihara1  +183 moreInstitutions (28)
TL;DR: Super-Kamiokande is the world's largest water Cherenkov detector, with net mass 50,000 tons as discussed by the authors, which collected 1678 live-days of data, observing neutrinos from the Sun, Earth's atmosphere, and the K2K long-baseline neutrino beam with high efficiency.
Abstract: Super-Kamiokande is the world's largest water Cherenkov detector, with net mass 50,000 tons. During the period April, 1996 to July, 2001, Super-Kamiokande I collected 1678 live-days of data, observing neutrinos from the Sun, Earth's atmosphere, and the K2K long-baseline neutrino beam with high efficiency. These data provided crucial information for our current understanding of neutrino oscillations, as well as setting stringent limits on nucleon decay. In this paper, we describe the detector in detail, including its site, configuration, data acquisition equipment, online and offline software, and calibration systems which were used during Super-Kamiokande I.

708 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: In this article, the Wilkinson Microwave Anisotropy Probe (WMAP) 5-year data were used to constrain the physics of cosmic inflation via Gaussianity, adiabaticity, the power spectrum of primordial fluctuations, gravitational waves, and spatial curvature.
Abstract: The Wilkinson Microwave Anisotropy Probe (WMAP) 5-year data provide stringent limits on deviations from the minimal, six-parameter Λ cold dark matter model. We report these limits and use them to constrain the physics of cosmic inflation via Gaussianity, adiabaticity, the power spectrum of primordial fluctuations, gravitational waves, and spatial curvature. We also constrain models of dark energy via its equation of state, parity-violating interaction, and neutrino properties, such as mass and the number of species. We detect no convincing deviations from the minimal model. The six parameters and the corresponding 68% uncertainties, derived from the WMAP data combined with the distance measurements from the Type Ia supernovae (SN) and the Baryon Acoustic Oscillations (BAO) in the distribution of galaxies, are: Ω b h 2 = 0.02267+0.00058 –0.00059, Ω c h 2 = 0.1131 ± 0.0034, ΩΛ = 0.726 ± 0.015, ns = 0.960 ± 0.013, τ = 0.084 ± 0.016, and at k = 0.002 Mpc-1. From these, we derive σ8 = 0.812 ± 0.026, H 0 = 70.5 ± 1.3 km s-1 Mpc–1, Ω b = 0.0456 ± 0.0015, Ω c = 0.228 ± 0.013, Ω m h 2 = 0.1358+0.0037 –0.0036, z reion = 10.9 ± 1.4, and t 0 = 13.72 ± 0.12 Gyr. With the WMAP data combined with BAO and SN, we find the limit on the tensor-to-scalar ratio of r 1 is disfavored even when gravitational waves are included, which constrains the models of inflation that can produce significant gravitational waves, such as chaotic or power-law inflation models, or a blue spectrum, such as hybrid inflation models. We obtain tight, simultaneous limits on the (constant) equation of state of dark energy and the spatial curvature of the universe: –0.14 < 1 + w < 0.12(95%CL) and –0.0179 < Ω k < 0.0081(95%CL). We provide a set of WMAP distance priors, to test a variety of dark energy models with spatial curvature. We test a time-dependent w with a present value constrained as –0.33 < 1 + w 0 < 0.21 (95% CL). Temperature and dark matter fluctuations are found to obey the adiabatic relation to within 8.9% and 2.1% for the axion-type and curvaton-type dark matter, respectively. The power spectra of TB and EB correlations constrain a parity-violating interaction, which rotates the polarization angle and converts E to B. The polarization angle could not be rotated more than –59 < Δα < 24 (95% CL) between the decoupling and the present epoch. We find the limit on the total mass of massive neutrinos of ∑m ν < 0.67 eV(95%CL), which is free from the uncertainty in the normalization of the large-scale structure data. The number of relativistic degrees of freedom (dof), expressed in units of the effective number of neutrino species, is constrained as N eff = 4.4 ± 1.5 (68%), consistent with the standard value of 3.04. Finally, quantitative limits on physically-motivated primordial non-Gaussianity parameters are –9 < f local NL < 111 (95% CL) and –151 < f equil NL < 253 (95% CL) for the local and equilateral models, respectively.

5,904 citations

Journal ArticleDOI
Nabila Aghanim1, Yashar Akrami2, Yashar Akrami3, Yashar Akrami4  +229 moreInstitutions (70)
TL;DR: In this article, the authors present cosmological parameter results from the full-mission Planck measurements of the cosmic microwave background (CMB) anisotropies, combining information from the temperature and polarization maps and the lensing reconstruction.
Abstract: We present cosmological parameter results from the final full-mission Planck measurements of the cosmic microwave background (CMB) anisotropies, combining information from the temperature and polarization maps and the lensing reconstruction Compared to the 2015 results, improved measurements of large-scale polarization allow the reionization optical depth to be measured with higher precision, leading to significant gains in the precision of other correlated parameters Improved modelling of the small-scale polarization leads to more robust constraints on manyparameters,withresidualmodellinguncertaintiesestimatedtoaffectthemonlyatthe05σlevelWefindgoodconsistencywiththestandard spatially-flat6-parameter ΛCDMcosmologyhavingapower-lawspectrumofadiabaticscalarperturbations(denoted“base ΛCDM”inthispaper), from polarization, temperature, and lensing, separately and in combination A combined analysis gives dark matter density Ωch2 = 0120±0001, baryon density Ωbh2 = 00224±00001, scalar spectral index ns = 0965±0004, and optical depth τ = 0054±0007 (in this abstract we quote 68% confidence regions on measured parameters and 95% on upper limits) The angular acoustic scale is measured to 003% precision, with 100θ∗ = 10411±00003Theseresultsareonlyweaklydependentonthecosmologicalmodelandremainstable,withsomewhatincreasederrors, in many commonly considered extensions Assuming the base-ΛCDM cosmology, the inferred (model-dependent) late-Universe parameters are: HubbleconstantH0 = (674±05)kms−1Mpc−1;matterdensityparameterΩm = 0315±0007;andmatterfluctuationamplitudeσ8 = 0811±0006 We find no compelling evidence for extensions to the base-ΛCDM model Combining with baryon acoustic oscillation (BAO) measurements (and consideringsingle-parameterextensions)weconstraintheeffectiveextrarelativisticdegreesoffreedomtobe Neff = 299±017,inagreementwith the Standard Model prediction Neff = 3046, and find that the neutrino mass is tightly constrained toPmν < 012 eV The CMB spectra continue to prefer higher lensing amplitudesthan predicted in base ΛCDM at over 2σ, which pulls some parameters that affect thelensing amplitude away from the ΛCDM model; however, this is not supported by the lensing reconstruction or (in models that also change the background geometry) BAOdataThejointconstraintwithBAOmeasurementsonspatialcurvatureisconsistentwithaflatuniverse, ΩK = 0001±0002Alsocombining with Type Ia supernovae (SNe), the dark-energy equation of state parameter is measured to be w0 = −103±003, consistent with a cosmological constant We find no evidence for deviations from a purely power-law primordial spectrum, and combining with data from BAO, BICEP2, and Keck Array data, we place a limit on the tensor-to-scalar ratio r0002 < 006 Standard big-bang nucleosynthesis predictions for the helium and deuterium abundances for the base-ΛCDM cosmology are in excellent agreement with observations The Planck base-ΛCDM results are in good agreement with BAO, SNe, and some galaxy lensing observations, but in slight tension with the Dark Energy Survey’s combined-probe results including galaxy clustering (which prefers lower fluctuation amplitudes or matter density parameters), and in significant, 36σ, tension with local measurements of the Hubble constant (which prefer a higher value) Simple model extensions that can partially resolve these tensions are not favoured by the Planck data

4,688 citations

Journal ArticleDOI
Nabila Aghanim1, Yashar Akrami2, Yashar Akrami3, Yashar Akrami4  +229 moreInstitutions (70)
TL;DR: In this paper, the cosmological parameter results from the final full-mission Planck measurements of the CMB anisotropies were presented, with good consistency with the standard spatially-flat 6-parameter CDM cosmology having a power-law spectrum of adiabatic scalar perturbations from polarization, temperature, and lensing separately and in combination.
Abstract: We present cosmological parameter results from the final full-mission Planck measurements of the CMB anisotropies. We find good consistency with the standard spatially-flat 6-parameter $\Lambda$CDM cosmology having a power-law spectrum of adiabatic scalar perturbations (denoted "base $\Lambda$CDM" in this paper), from polarization, temperature, and lensing, separately and in combination. A combined analysis gives dark matter density $\Omega_c h^2 = 0.120\pm 0.001$, baryon density $\Omega_b h^2 = 0.0224\pm 0.0001$, scalar spectral index $n_s = 0.965\pm 0.004$, and optical depth $\tau = 0.054\pm 0.007$ (in this abstract we quote $68\,\%$ confidence regions on measured parameters and $95\,\%$ on upper limits). The angular acoustic scale is measured to $0.03\,\%$ precision, with $100\theta_*=1.0411\pm 0.0003$. These results are only weakly dependent on the cosmological model and remain stable, with somewhat increased errors, in many commonly considered extensions. Assuming the base-$\Lambda$CDM cosmology, the inferred late-Universe parameters are: Hubble constant $H_0 = (67.4\pm 0.5)$km/s/Mpc; matter density parameter $\Omega_m = 0.315\pm 0.007$; and matter fluctuation amplitude $\sigma_8 = 0.811\pm 0.006$. We find no compelling evidence for extensions to the base-$\Lambda$CDM model. Combining with BAO we constrain the effective extra relativistic degrees of freedom to be $N_{\rm eff} = 2.99\pm 0.17$, and the neutrino mass is tightly constrained to $\sum m_ u< 0.12$eV. The CMB spectra continue to prefer higher lensing amplitudes than predicted in base -$\Lambda$CDM at over $2\,\sigma$, which pulls some parameters that affect the lensing amplitude away from the base-$\Lambda$CDM model; however, this is not supported by the lensing reconstruction or (in models that also change the background geometry) BAO data. (Abridged)

3,077 citations

Journal ArticleDOI
Shadab Alam1, Metin Ata2, Stephen Bailey3, Florian Beutler3, Dmitry Bizyaev4, Dmitry Bizyaev5, Jonathan Blazek6, Adam S. Bolton7, Joel R. Brownstein7, Angela Burden8, Chia-Hsun Chuang9, Chia-Hsun Chuang2, Johan Comparat9, Antonio J. Cuesta10, Kyle S. Dawson7, Daniel J. Eisenstein11, Stephanie Escoffier12, Héctor Gil-Marín13, Héctor Gil-Marín14, Jan Niklas Grieb15, Nick Hand16, Shirley Ho1, Karen Kinemuchi4, D. Kirkby17, Francisco S. Kitaura16, Francisco S. Kitaura3, Francisco S. Kitaura2, Elena Malanushenko4, Viktor Malanushenko4, Claudia Maraston18, Cameron K. McBride11, Robert C. Nichol18, Matthew D. Olmstead19, Daniel Oravetz4, Nikhil Padmanabhan8, Nathalie Palanque-Delabrouille, Kaike Pan4, Marcos Pellejero-Ibanez20, Marcos Pellejero-Ibanez21, Will J. Percival18, Patrick Petitjean22, Francisco Prada20, Francisco Prada9, Adrian M. Price-Whelan23, Beth Reid3, Beth Reid16, Sergio Rodríguez-Torres20, Sergio Rodríguez-Torres9, Natalie A. Roe3, Ashley J. Ross6, Ashley J. Ross18, Nicholas P. Ross24, Graziano Rossi25, Jose Alberto Rubino-Martin21, Jose Alberto Rubino-Martin20, Shun Saito15, Salvador Salazar-Albornoz15, Lado Samushia26, Ariel G. Sánchez15, Siddharth Satpathy1, David J. Schlegel3, Donald P. Schneider27, Claudia G. Scóccola28, Claudia G. Scóccola29, Claudia G. Scóccola9, Hee-Jong Seo30, Erin Sheldon31, Audrey Simmons4, Anže Slosar31, Michael A. Strauss23, Molly E. C. Swanson11, Daniel Thomas18, Jeremy L. Tinker32, Rita Tojeiro33, Mariana Vargas Magaña34, Mariana Vargas Magaña1, Jose Alberto Vazquez31, Licia Verde, David A. Wake35, David A. Wake36, Yuting Wang18, Yuting Wang37, David H. Weinberg6, Martin White16, Martin White3, W. Michael Wood-Vasey38, Christophe Yèche, Idit Zehavi39, Zhongxu Zhai33, Gong-Bo Zhao37, Gong-Bo Zhao18 
TL;DR: In this article, the authors present cosmological results from the final galaxy clustering data set of the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III.
Abstract: We present cosmological results from the final galaxy clustering data set of the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III. Our combined galaxy sample comprises 1.2 million massive galaxies over an effective area of 9329 deg^2 and volume of 18.7 Gpc^3, divided into three partially overlapping redshift slices centred at effective redshifts 0.38, 0.51 and 0.61. We measure the angular diameter distance and Hubble parameter H from the baryon acoustic oscillation (BAO) method, in combination with a cosmic microwave background prior on the sound horizon scale, after applying reconstruction to reduce non-linear effects on the BAO feature. Using the anisotropic clustering of the pre-reconstruction density field, we measure the product D_MH from the Alcock–Paczynski (AP) effect and the growth of structure, quantified by fσ_8(z), from redshift-space distortions (RSD). We combine individual measurements presented in seven companion papers into a set of consensus values and likelihoods, obtaining constraints that are tighter and more robust than those from any one method; in particular, the AP measurement from sub-BAO scales sharpens constraints from post-reconstruction BAOs by breaking degeneracy between D_M and H. Combined with Planck 2016 cosmic microwave background measurements, our distance scale measurements simultaneously imply curvature Ω_K = 0.0003 ± 0.0026 and a dark energy equation-of-state parameter w = −1.01 ± 0.06, in strong affirmation of the spatially flat cold dark matter (CDM) model with a cosmological constant (ΛCDM). Our RSD measurements of fσ_8, at 6 per cent precision, are similarly consistent with this model. When combined with supernova Ia data, we find H_0 = 67.3 ± 1.0 km s^−1 Mpc^−1 even for our most general dark energy model, in tension with some direct measurements. Adding extra relativistic species as a degree of freedom loosens the constraint only slightly, to H_0 = 67.8 ± 1.2 km s^−1 Mpc^−1. Assuming flat ΛCDM, we find Ω_m = 0.310 ± 0.005 and H_0 = 67.6 ± 0.5 km s^−1 Mpc^−1, and we find a 95 per cent upper limit of 0.16 eV c^−2 on the neutrino mass sum.

2,413 citations