This paper presents cosmological results based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation. Our results are in very good agreement with the 2013 analysis of the Planck nominal-mission temperature data, but with increased precision. The temperature and polarization power spectra are consistent with the standard spatially-flat 6-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations (denoted "base ΛCDM" in this paper). From the Planck temperature data combined with Planck lensing, for this cosmology we find a Hubble constant, H 0 = (67.8 ± 0.9) km s −1 Mpc −1 , a matter density parameter Ω m = 0.308 ± 0.012, and a tilted scalar spectral index with n s = 0.968 ± 0.006, consistent with the 2013 analysis. Note that in this abstract we quote 68% confidence limits on measured parameters and 95% upper limits on other parameters. We present the first results of polarization measurements with the Low Frequency Instrument at large angular scales. Combined with the Planck temperature and lensing data, these measurements give a reionization optical depth of τ = 0.066 ± 0.016, corresponding to a reionization redshift of z re = 8.8+1.7 −1.4 . These results are consistent with those from WMAP polarization measurements cleaned for dust emission using 353-GHz polarization maps from the High Frequency Instrument. We find no evidence for any departure from base ΛCDM in the neutrino sector of the theory; for example, combining Planck observations with other astrophysical data we find N eff = 3.15 ± 0.23 for the effective number of relativistic degrees of freedom, consistent with the value N eff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to m ν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero, with |Ω K | < 0.005. Adding a tensor component as a single-parameter extension to base ΛCDM we find an upper limit on the tensor-to-scalar ratio of r 0.002 < 0.11, consistent with the Planck 2013 results and consistent with the B-mode polarization constraints from a joint analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP B-mode data to our analysis leads to a tighter constraint of r 0.002 < 0.09 and disfavours inflationary models with a V(φ) ∝ φ 2 potential. The addition of Planck polarization data leads to strong constraints on deviations from a purely adiabatic spectrum of fluctuations. We find no evidence for any contribution from isocurvature perturbations or from cosmic defects. Combining Planck data with other astrophysical data, including Type Ia supernovae, the equation of state of dark energy is constrained to w = −1.006 ± 0.045, consistent with the expected Corresponding author: G. Efstathiou, e-mail: gpe@ast.cam.ac.ukArticle published by EDP Sciences A13, page 1 of 63 A&A 594, A13 (2016) value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundanc...
The European Space Agency's Planck satellite, dedicated to studying the early Universe and its subsequent evolution, was launched 14 May 2009 and has been scanning the microwave and submillimetre sky continuously since 12 August 2009. In March 2013, ESA and the Planck Collaboration released the initial cosmology products based on the first 15.5 months of Planck data, along with a set of scientific and technical papers and a web-based explanatory supplement. This paper gives an overview of the mission and its performance, the processing, analysis, and characteristics of the data, the scientific results, and the science data products and papers in the release. The science products include maps of the cosmic microwave background (CMB) and diffuse extragalactic foregrounds, a catalogue of compact Galactic and extragalactic sources, and a list of sources detected through the Sunyaev-Zeldovich effect. The likelihood code used to assess cosmological models against the Planck data and a lensing likelihood are described. Scientific results include robust support for the standard six-parameter ΛCDM model of cosmology and improved measurements of its parameters, including a highly significant deviation from scale invariance of the primordial power spectrum. The Planck values for these parameters and others derived from them are significantly different from those previously determined. Several large-scale anomalies in the temperature distribution of the CMB, first detected by WMAP, are confirmed with higher confidence. Planck sets new limits on the number and mass of neutrinos, and has measured gravitational lensing of CMB anisotropies at greater than 25σ. Planck finds no evidence for non-Gaussianity in the CMB. Planck's results agree well with results from the measurements of baryon acoustic oscillations. Planck finds a lower Hubble constant than found in some more local measures. Some tension is also present between the amplitude of matter fluctuations (σ 8 ) derived from CMB data and that derived from Sunyaev-Zeldovich data. The Planck and WMAP power spectra are offset from each other by an average level of about 2% around the first acoustic peak. Analysis of Planck polarization data is not yet mature, therefore polarization results are not released, although the robust detection of E-mode polarization around CMB hot and cold spots is shown graphically.
This paper presents the Planck 2015 likelihoods, statistical descriptions of the 2-point correlation functions of the cosmic microwave background (CMB) temperature and polarization fluctuations that account for relevant uncertainties, both instrumental and astrophysical in nature. They are based on the same hybrid approach used for the previous release, i.e., a pixel-based likelihood at low multipoles ( < 30) and a Gaussian approximation to the distribution of cross-power spectra at higher multipoles. The main improvements are the use of more and better processed data and of Planck polarization information, along with more detailed models of foregrounds and instrumental uncertainties. The increased redundancy brought by more than doubling the amount of data analysed enables further consistency checks and enhanced immunity to systematic effects. It also improves the constraining power of Planck, in particular with regard to small-scale foreground properties. Progress in the modelling of foreground emission enables the retention of a larger fraction of the sky to determine the properties of the CMB, which also contributes to the enhanced precision of the spectra. Improvements in data processing and instrumental modelling further reduce uncertainties. Extensive tests establish the robustness and accuracy of the likelihood results, from temperature alone, from polarization alone, and from their combination. For temperature, we also perform a full likelihood analysis of realistic end-to-end simulations of the instrumental response to the sky, which were fed into the actual data processing pipeline; this does not reveal biases from residual low-level instrumental systematics. Even with the increase in precision and robustness, the ΛCDM cosmological model continues to offer a very good fit to the Planck data. The slope of the primordial scalar fluctuations, n s , is confirmed smaller than unity at more than 5σ from Planck alone. We further validate the robustness of the likelihood results against specific extensions to the baseline cosmology, which are particularly sensitive to data at high multipoles. For instance, the effective number of neutrino species remains compatible with the canonical value of 3.046. For this first detailed analysis of Planck polarization spectra, we concentrate at high multipoles on the E modes, leaving the analysis of the weaker B modes to future work. At low multipoles we use temperature maps at all Planck frequencies along with a subset of polarization data. These data take advantage of Planck's wide frequency coverage to improve the separation of CMB and foreground emission. Within the baseline ΛCDM cosmology this requires τ = 0.078 ± 0.019 for the reionization optical depth, which is significantly lower than estimates without the use of high-frequency data for explicit monitoring of dust emission. At high multipoles we detect residual systematic errors in E polarization, typically at the µK 2 level; we therefore choose to retain temperature information alone for high multipoles a...
BACKGROUNDIn a previous analysis of this phase 3 trial, first-line ribociclib plus letrozole resulted in significantly longer progression-free survival than letrozole alone among postmenopausal patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether overall survival would also be longer with ribociclib was not known. METHODSHere we report the results of the protocol-specified final analysis of overall survival, a key secondary end point. Patients were randomly assigned in a 1:1 ratio to receive either ribociclib or placebo in combination with letrozole. Overall survival was assessed with the use of a stratified log-rank test and summarized with the use of Kaplan-Meier methods after 400 deaths had occurred. A hierarchical testing strategy was used for the analysis of progression-free survival and overall survival to ensure the validity of the findings. RESULTSAfter a median follow-up of 6.6 years, 181 deaths had occurred among 334 patients (54.2%) in the ribociclib group and 219 among 334 (65.6%) in the placebo group. Ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole. Median overall survival was 63.9 months (95% confidence interval [CI], 52.4 to 71.0) with ribociclib plus letrozole and 51.4 months (95% CI, 47.2 to 59.7) with placebo plus letrozole (hazard ratio for death, 0.76; 95% CI, 0.63 to 0.93; two-sided P = 0.008). No new safety signals were observed. CONCLUSIONSFirst-line therapy with ribociclib plus letrozole showed a significant overall survival benefit as compared with placebo plus letrozole in patients with HR-positive, HER2-negative advanced breast cancer. Median overall survival was more than 12 months longer with ribociclib than with placebo. (Funded by Novartis; MONALEESA-2 ClinicalTrials.gov number, NCT01958021.
The European Space Agency's Planck satellite, which is dedicated to studying the early Universe and its subsequent evolution, was launched on 14 May 2009. It scanned the microwave and submillimetre sky continuously between 12 August 2009 and 23 October 2013. In February 2015, ESA and the Planck Collaboration released the second set of cosmology products based on data from the entire Planck mission, including both temperature and polarization, along with a set of scientific and technical papers and a web-based explanatory supplement. This paper gives an overview of the main characteristics of the data and the data products in the release, as well as the associated cosmological and astrophysical science results and papers. The data products include maps of the cosmic microwave background (CMB), the thermal Sunyaev-Zeldovich effect, diffuse foregrounds in temperature and polarization, catalogues of compact Galactic and extragalactic sources (including separate catalogues of Corresponding author: C. R. Lawrence, e-mail: charles.lawrence@jpl.nasa.govArticle published by EDP Sciences A1, page 1 of 38 A&A 594, A1 (2016) Sunyaev-Zeldovich clusters and Galactic cold clumps), and extensive simulations of signals and noise used in assessing uncertainties and the performance of the analysis methods. The likelihood code used to assess cosmological models against the Planck data is described, along with a CMB lensing likelihood. Scientific results include cosmological parameters derived from CMB power spectra, gravitational lensing, and cluster counts, as well as constraints on inflation, non-Gaussianity, primordial magnetic fields, dark energy, and modified gravity, and new results on low-frequency Galactic foregrounds.
The extragalactic background light at far-infrared wavelengths 1-3 originates from opticallyfaint, dusty, star-forming galaxies in the universe with star-formation rates at the level of a few hundred solar masses per year 4 . Due to the relatively poor spatial resolution of farinfrared telescopes 5, 6 , the faint sub-millimetre galaxies are challenging to study individually. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations 7-10 . A previous attempt 11 at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model 12 . Here we report a clear detection of the excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350, and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter halos with a minimum mass of log[M min /M ⊙ ] = 11.5 +0.7 −0.2 at 350 µm. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the universe 13 , and is lower than that predicted by semi-analytical models for galaxy formation 14 .Despite recent successes in attributing most of the extragalactic background light at submillimetre wavelengths to known galaxy populations through stacking analyses 15-17 , we have not individually detected the faint galaxies that are responsible for more than 85% of the total extragalactic intensity at these wavelengths 18 . The faint star-forming galaxies are expected to trace the large-scale structure of the Universe, especially in models where galaxy formation and evolution is closely connected to dark matter halos. While not individually detected in low resolution observations, the clustering of galaxies is expected to leave a distinct signature in the total intensity variations at sub-millimetre wavelengths. The amplitude of the power spectrum of intensity vari-2 ations as a function of the angular scale provides details on the redshift distribution and the dark matter halo mass scale of dusty, star-forming galaxies in the universe 7 .For this analysis, we used data from the Herschel Multi-tiered Extra-galactic survey (HerMES 18 ), taken with the Spectral and Photometric Imaging Receiver (SPIRE 19 ) onboard the Herschel Space Observatory 20 , during the Science Demonstration Phase (SDP) of Herschel. The data are composed of a wide 218 ′ by 218 ′ area in the Lockman Hole complemented by a narrow, but very deep (30 repeated scans), map of the Great Observatories Origins Deep Survey (GOODS) North field covering 30 ′ by 30 ′ . These fields have been very well studied at other wavelengths and they are known to have a low Galactic dust density, making it easier to distinguish the extragalactic component we wish to study. The observing time to complete each of the two fields was about 13.5 hours, observing simultaneously at 250, 350, and 500 µm.To limit the influence of a few ...
We quantify the fraction of the cosmic infrared background (CIB) that originates from galaxies identified in the UV/optical/near-infrared by stacking 81,250 (∼ 35.7 arcmin −2 ) K -selected sources (K AB < 24.0) split according to their rest-frame U − V vs. V − J colors into 72,216 star-forming and 9,034 quiescent galaxies, on maps from Spitzer /MIPS (24 µm), Herschel /PACS (100, 160 µm), Herschel /SPIRE (250, 350, 500 µm), and AzTEC (1100 µm). The fraction of the CIB resolved by our catalog is (69 ± 15)% at 24 µm, (78 ± 17)% at 70 µm, (58 ± 13)% at 100 µm, (78 ± 18)% at 160 µm, (80 ± 17)% at 250 µm, (69 ± 14)% at 350 µm, (65 ± 12)% at 500 µm, and (45 ± 8)% at 1100 µm. Of that total, about 95% originates from star-forming galaxies, while the remaining 5% is from apparently quiescent galaxies. The CIB at λ < ∼ 200 µm appears to be sourced predominantly from galaxies at z < ∼ 1, while at λ > ∼ 200 µm the bulk originates from 1 < ∼ z < ∼ 2. Galaxies with stellar masses log(M/M ⊙ ) = 9.5-11 are responsible for the majority of the CIB, with those in the log(M/M ⊙ ) = 9.5-10 bin contributing mostly at λ < 250 µm, and those in the log(M/M ⊙ ) = 10-11 bin dominating at λ > 350 µm. The contribution from galaxies in the log(M/M ⊙ ) = 9.0-9.5 (lowest) and log(M/M ⊙ ) = 11.0-12.0 (highest) stellar-mass bins contribute the least-both of order 5%-although the highest stellar-mass bin is a significant contributor to the luminosity density at z > ∼ 2. The luminosities of the galaxies responsible for the CIB shifts from combinations of "normal" and luminous infrared galaxies (LIRGs) at λ < ∼ 160 µm, to LIRGs at 160 < ∼ λ < ∼ 500 µm, to finally LIRGs and ultra-luminous infrared galaxies (ULIRGs) at λ > ∼ 500 µm. Stacking analyses were performed using simstack, a novel algorithm designed to account for possible biases in the stacked flux density due to clustering. It is made available to the public at
We investigate the cosmological effects of a neutrino interaction with cold dark-matter. We postulate a neutrino that interacts with a ''neutrino-interacting dark-matter'' (NIDM) particle with an elasticscattering cross section that either decreases with temperature as T 2 or remains constant with temperature. The neutrino-dark-matter interaction results in a neutrino-dark-matter fluid with pressure, and this pressure results in diffusion-damped oscillations in the matter power spectrum, analogous to the acoustic oscillations in the baryon-photon fluid. We discuss the bounds from the Sloan Digital Sky Survey on the NIDM opacity (ratio of cross section to NIDM-particle mass) and compare with the constraint from observation of neutrinos from supernova 1987A. If only a fraction of the dark matter interacts with neutrinos, then NIDM oscillations may affect current cosmological constraints from measurements of galaxy clustering. We discuss how detection of NIDM oscillations would suggest a particle-antiparticle asymmetry in the dark-matter sector.
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