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Andreas Papageorgiou

Bio: Andreas Papageorgiou is an academic researcher from Cardiff University. The author has contributed to research in topics: Galaxy & Redshift. The author has an hindex of 60, co-authored 158 publications receiving 15708 citations. Previous affiliations of Andreas Papageorgiou include Arizona State University & Imperial College London.


Papers
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Journal ArticleDOI
Matthew Joseph Griffin, Alain Abergel1, A. Abreu, Peter A. R. Ade2  +186 moreInstitutions (27)
TL;DR: The Spectral and Photometric Imaging REceiver (SPIRE) is the Herschel Space Observatory's sub-millimetre camera and spectrometer as discussed by the authors, which is used for image and spectroscopic data acquisition.
Abstract: The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer It contains a three-band imaging photometer operating at 250, 350 and 500 mu m, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 mu m (447-1550 GHz) The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 03 K The photometer has a field of view of 4' x 8', observed simultaneously in the three spectral bands Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired The spectrometer has an approximately circular field of view with a diameter of 26' The spectral resolution can be adjusted between 12 and 25 GHz by changing the stroke length of the FTS scan mirror Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 15-2

2,425 citations

Journal ArticleDOI
Seb Oliver1, James J. Bock2, James J. Bock3, Bruno Altieri4, Alexandre Amblard5, V. Arumugam6, Herve Aussel7, Tom Babbedge8, Alexandre Beelen9, Matthieu Béthermin7, Matthieu Béthermin9, Andrew Blain2, Alessandro Boselli10, C. Bridge2, Drew Brisbin11, V. Buat10, Denis Burgarella10, N. Castro-Rodríguez12, N. Castro-Rodríguez13, Antonio Cava14, P. Chanial7, Michele Cirasuolo15, David L. Clements8, A. Conley16, L. Conversi4, Asantha Cooray2, Asantha Cooray17, C. D. Dowell2, C. D. Dowell3, Elizabeth Dubois1, Eli Dwek18, Simon Dye19, Stephen Anthony Eales20, David Elbaz7, Duncan Farrah1, A. Feltre21, P. Ferrero13, P. Ferrero12, N. Fiolet22, N. Fiolet9, M. Fox8, Alberto Franceschini21, Walter Kieran Gear20, E. Giovannoli10, Jason Glenn16, Yan Gong17, E. A. González Solares23, Matthew Joseph Griffin20, Mark Halpern24, Martin Harwit, Evanthia Hatziminaoglou, Sebastien Heinis10, Peter Hurley1, Ho Seong Hwang7, A. Hyde8, Edo Ibar15, O. Ilbert10, K. G. Isaak25, Rob Ivison6, Rob Ivison15, Guilaine Lagache9, E. Le Floc'h7, L. R. Levenson3, L. R. Levenson2, B. Lo Faro21, Nanyao Y. Lu2, S. C. Madden7, Bruno Maffei26, Georgios E. Magdis7, G. Mainetti21, Lucia Marchetti21, G. Marsden24, J. Marshall3, J. Marshall2, A. M. J. Mortier8, Hien Nguyen2, Hien Nguyen3, B. O'Halloran8, Alain Omont22, Mat Page27, P. Panuzzo7, Andreas Papageorgiou20, H. Patel8, Chris Pearson28, Chris Pearson29, Ismael Perez-Fournon13, Ismael Perez-Fournon12, Michael Pohlen20, Jonathan Rawlings27, Gwenifer Raymond20, Dimitra Rigopoulou29, Dimitra Rigopoulou30, L. Riguccini7, D. Rizzo8, Giulia Rodighiero21, Isaac Roseboom6, Isaac Roseboom1, Michael Rowan-Robinson8, M. Sanchez Portal4, Benjamin L. Schulz2, Douglas Scott24, Nick Seymour31, Nick Seymour27, D. L. Shupe2, A. J. Smith1, Jamie Stevens32, M. Symeonidis27, Markos Trichas33, K. E. Tugwell27, Mattia Vaccari21, Ivan Valtchanov4, Joaquin Vieira2, Marco P. Viero2, L. Vigroux22, Lifan Wang1, Robyn L. Ward1, Julie Wardlow17, G. Wright15, C. K. Xu2, Michael Zemcov3, Michael Zemcov2 
TL;DR: The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy program designed to map a set of nested fields totalling ∼380deg^2 as mentioned in this paper.
Abstract: The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy programme designed to map a set of nested fields totalling ∼380 deg^2. Fields range in size from 0.01 to ∼20 deg^2, using the Herschel-Spectral and Photometric Imaging Receiver (SPIRE) (at 250, 350 and 500 μm) and the Herschel-Photodetector Array Camera and Spectrometer (PACS) (at 100 and 160 μm), with an additional wider component of 270 deg^2 with SPIRE alone. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the reprocessed optical and ultraviolet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multiwavelength understanding of galaxy formation and evolution. The survey will detect of the order of 100 000 galaxies at 5σ in some of the best-studied fields in the sky. Additionally, HerMES is closely coordinated with the PACS Evolutionary Probe survey. Making maximum use of the full spectrum of ancillary data, from radio to X-ray wavelengths, it is designed to facilitate redshift determination, rapidly identify unusual objects and understand the relationships between thermal emission from dust and other processes. Scientific questions HerMES will be used to answer include the total infrared emission of galaxies, the evolution of the luminosity function, the clustering properties of dusty galaxies and the properties of populations of galaxies which lie below the confusion limit through lensing and statistical techniques. This paper defines the survey observations and data products, outlines the primary scientific goals of the HerMES team, and reviews some of the early results.

852 citations

Journal ArticleDOI
TL;DR: The pre-print version of the Published Article can be accessed from the link below - Copyright @ 2010 Springer Verlag as discussed by the authors, which can be viewed as a preprint of the published article.
Abstract: This is the pre-print version of the Published Article, which can be accessed from the link below - Copyright @ 2010 Springer Verlag

717 citations

Journal ArticleDOI
Seb Oliver1, James J. Bock2, James J. Bock3, Bruno Altieri4, Alexandre Amblard5, V. Arumugam6, Herve Aussel7, Tom Babbedge8, Alexandre Beelen, Matthieu Béthermin7, Andrew Blain2, Alessandro Boselli9, C. Bridge2, Drew Brisbin10, V. Buat9, Denis Burgarella9, N. Castro-Rodríguez11, N. Castro-Rodríguez12, Antonio Cava13, P. Chanial7, Michele Cirasuolo14, David L. Clements8, A. Conley15, L. Conversi4, Asantha Cooray16, Asantha Cooray2, C. D. Dowell2, C. D. Dowell3, Elizabeth Dubois1, Eli Dwek17, Simon Dye18, Stephen Anthony Eales19, David Elbaz7, Duncan Farrah1, A. Feltre20, P. Ferrero12, P. Ferrero11, N. Fiolet21, M. Fox8, Alberto Franceschini20, Walter Kieran Gear19, E. Giovannoli9, Jason Glenn15, Yan Gong16, E. A. González Solares22, Matthew Joseph Griffin19, Mark Halpern23, Martin Harwit, Evanthia Hatziminaoglou, Sebastien Heinis9, Peter Hurley1, Ho Seong Hwang7, A. Hyde8, Edo Ibar14, O. Ilbert9, K. G. Isaak24, Rob Ivison6, Rob Ivison14, Guilaine Lagache, E. Le Floc'h7, L. R. Levenson2, L. R. Levenson3, B. Lo Faro20, Nanyao Y. Lu2, S. C. Madden7, Bruno Maffei25, Georgios E. Magdis7, G. Mainetti20, Lucia Marchetti20, G. Marsden23, J. Marshall2, J. Marshall3, A. M. J. Mortier8, Hien Nguyen2, Hien Nguyen3, B. O'Halloran8, Alain Omont21, Mat Page26, P. Panuzzo7, Andreas Papageorgiou19, H. Patel8, Chris Pearson27, Chris Pearson28, Ismael Perez-Fournon11, Ismael Perez-Fournon12, Michael Pohlen19, Jonathan Rawlings26, Gwenifer Raymond19, Dimitra Rigopoulou27, Dimitra Rigopoulou29, L. Riguccini7, D. Rizzo8, Giulia Rodighiero20, Isaac Roseboom1, Isaac Roseboom6, Michael Rowan-Robinson8, M. Sanchez Portal4, Benjamin L. Schulz2, Douglas Scott23, Nick Seymour30, Nick Seymour26, D. L. Shupe2, A. J. Smith1, Jamie Stevens31, M. Symeonidis26, Markos Trichas32, K. E. Tugwell26, Mattia Vaccari20, Ivan Valtchanov4, Joaquin Vieira2, Marco P. Viero2, L. Vigroux21, Lifan Wang1, Robyn L. Ward1, Julie Wardlow16, G. Wright14, C. K. Xu2, Michael Zemcov2, Michael Zemcov3 
TL;DR: The Herschel Multi-tiered Extragalactic Survey (HerMES) is a legacy program designed to map a set of nested fields totalling ~380 deg^2 as mentioned in this paper.
Abstract: The Herschel Multi-tiered Extragalactic Survey, HerMES, is a legacy program designed to map a set of nested fields totalling ~380 deg^2. Fields range in size from 0.01 to ~20 deg^2, using Herschel-SPIRE (at 250, 350 and 500 \mu m), and Herschel-PACS (at 100 and 160 \mu m), with an additional wider component of 270 deg^2 with SPIRE alone. These bands cover the peak of the redshifted thermal spectral energy distribution from interstellar dust and thus capture the re-processed optical and ultra-violet radiation from star formation that has been absorbed by dust, and are critical for forming a complete multi-wavelength understanding of galaxy formation and evolution. The survey will detect of order 100,000 galaxies at 5\sigma in some of the best studied fields in the sky. Additionally, HerMES is closely coordinated with the PACS Evolutionary Probe survey. Making maximum use of the full spectrum of ancillary data, from radio to X-ray wavelengths, it is designed to: facilitate redshift determination; rapidly identify unusual objects; and understand the relationships between thermal emission from dust and other processes. Scientific questions HerMES will be used to answer include: the total infrared emission of galaxies; the evolution of the luminosity function; the clustering properties of dusty galaxies; and the properties of populations of galaxies which lie below the confusion limit through lensing and statistical techniques. This paper defines the survey observations and data products, outlines the primary scientific goals of the HerMES team, and reviews some of the early results.

707 citations

Journal ArticleDOI
Stephen Anthony Eales1, Loretta Dunne2, David L. Clements3, Asantha Cooray4, G. de Zotti5, G. de Zotti6, Simon Dye1, Rob Ivison7, Matt J. Jarvis8, Guilaine Lagache9, Guilaine Lagache10, Steve Maddox2, Mattia Negrello11, Steve Serjeant11, Mark Thompson8, E. van Kampen12, Alexandre Amblard4, Paola Andreani12, Maarten Baes13, Alexandre Beelen10, Alexandre Beelen9, George J. Bendo3, Dominic J. Benford12, Dominic J. Benford14, Frank Bertoldi15, Frank Bertoldi13, James J. Bock16, D. G. Bonfield8, Alessandro Boselli17, C. Bridge9, V. Buat17, Denis Burgarella17, Raymond G. Carlberg18, Antonio Cava, Pierre Chanial3, S. Charlot19, N. Christopher20, Peter Coles1, Luca Cortese1, Aliakbar Dariush1, E. da Cunha21, Gavin Dalton20, Gavin Dalton22, Luigi Danese23, Helmut Dannerbauer23, Simon P. Driver, James Dunlop7, Lulu Fan18, Duncan Farrah18, David T. Frayer16, Carlos S. Frenk24, James E. Geach24, Jonathan P. Gardner14, Haley Louise Gomez1, J. González-Nuevo18, Eduardo Gonzalez-Solares25, Matthew Joseph Griffin1, Martin J. Hardcastle8, Evanthia Hatziminaoglou12, D. Herranz26, David H. Hughes, Edo Ibar7, Woong-Seob Jeong27, Cedric G. Lacey24, Andrea Lapi28, Andy Lawrence7, Myung Gyoon Lee29, Lerothodi Leonard Leeuw28, Jochen Liske12, M. López-Caniego23, Th. Müller23, Kirpal Nandra3, P. Panuzzo30, Andreas Papageorgiou1, G. Patanchon30, John A. Peacock7, C. P. Pearson22, Steven Phillipps, Michael Pohlen1, Cristina Popescu31, Steve Rawlings20, E. E. Rigby2, M. Rigopoulou20, Aaron S. G. Robotham32, Giulia Rodighiero6, Anne E. Sansom31, Benjamin L. Schulz, Douglas Scott33, D. J. B. Smith2, B. Sibthorpe7, Ian Smail24, Jamie Stevens8, William J. Sutherland34, Tsutomu T. Takeuchi35, Jonathan Tedds36, P. Temi37, Richard J. Tuffs23, Markos Trichas3, Mattia Vaccari6, Ivan Valtchanov38, P. van der Werf39, Aprajita Verma20, J. Vieria39, Catherine Vlahakis39, Glenn J. White11, Glenn J. White22 
TL;DR: The Herschel ATLAS project as discussed by the authors is the largest open-time key project that will be carried out on the Herschel Space Observatory, and it will survey 570 deg2 of the extragalactic sky, 4 times larger than all the other Herschel extragala surveys combined, in five far-infrared and submillimeter bands.
Abstract: The Herschel ATLAS is the largest open-time key project that will be carried out on the Herschel Space Observatory. It will survey 570 deg2 of the extragalactic sky, 4 times larger than all the other Herschel extragalactic surveys combined, in five far-infrared and submillimeter bands. We describe the survey, the complementary multiwavelength data sets that will be combined with the Herschel data, and the six major science programs we are undertaking. Using new models based on a previous submillimeter survey of galaxies, we present predictions of the properties of the ATLAS sources in other wave bands.

610 citations


Cited by
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Journal ArticleDOI
Peter A. R. Ade1, Nabila Aghanim2, Monique Arnaud3, M. Ashdown4  +334 moreInstitutions (82)
TL;DR: In this article, the authors present a cosmological analysis based on full-mission Planck observations of temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation.
Abstract: 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, H0 = (67.8 ± 0.9) km s-1Mpc-1, a matter density parameter Ωm = 0.308 ± 0.012, and a tilted scalar spectral index with ns = 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 . 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 Neff = 3.15 ± 0.23 for the effective number of relativistic degrees of freedom, consistent with the value Neff = 3.046 of the Standard Model of particle physics. The sum of neutrino masses is constrained to ∑ mν < 0.23 eV. The spatial curvature of our Universe is found to be very close to zero, with | ΩK | < 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 r0.002< 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 r0.002 < 0.09 and disfavours inflationarymodels with a V(φ) ∝ φ2 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 value for a cosmological constant. The standard big bang nucleosynthesis predictions for the helium and deuterium abundances for the best-fit Planck base ΛCDM cosmology are in excellent agreement with observations. We also constraints on annihilating dark matter and on possible deviations from the standard recombination history. In neither case do we find no evidence for new physics. The Planck results for base ΛCDM are in good agreement with baryon acoustic oscillation data and with the JLA sample of Type Ia supernovae. However, as in the 2013 analysis, the amplitude of the fluctuation spectrum is found to be higher than inferred from some analyses of rich cluster counts and weak gravitational lensing. We show that these tensions cannot easily be resolved with simple modifications of the base ΛCDM cosmology. Apart from these tensions, the base ΛCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.

10,728 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB, which are consistent with the six-parameter inflationary LCDM cosmology.
Abstract: We present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB. These data are consistent with the six-parameter inflationary LCDM cosmology. From the Planck temperature and lensing data, for this cosmology we find a Hubble constant, H0= (67.8 +/- 0.9) km/s/Mpc, a matter density parameter Omega_m = 0.308 +/- 0.012 and a scalar spectral index with n_s = 0.968 +/- 0.006. (We quote 68% errors on measured parameters and 95% limits on other parameters.) Combined with Planck temperature and lensing data, Planck LFI polarization measurements lead to a reionization optical depth of tau = 0.066 +/- 0.016. Combining Planck with other astrophysical data we find N_ eff = 3.15 +/- 0.23 for the effective number of relativistic degrees of freedom and the sum of neutrino masses is constrained to < 0.23 eV. Spatial curvature is found to be |Omega_K| < 0.005. For LCDM we find a limit on the tensor-to-scalar ratio of r <0.11 consistent with the B-mode constraints from an analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP data leads to a tighter constraint of r < 0.09. We find no evidence for isocurvature perturbations or cosmic defects. The equation of state of dark energy is constrained to w = -1.006 +/- 0.045. Standard big bang nucleosynthesis predictions for the Planck LCDM cosmology are in excellent agreement with observations. We investigate annihilating dark matter and deviations from standard recombination, finding no evidence for new physics. The Planck results for base LCDM are in agreement with BAO data and with the JLA SNe sample. However the amplitude of the fluctuations is found to be higher than inferred from rich cluster counts and weak gravitational lensing. Apart from these tensions, the base LCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets.

9,745 citations

Journal ArticleDOI
Peter A. R. Ade1, Nabila Aghanim2, C. Armitage-Caplan3, Monique Arnaud4  +324 moreInstitutions (70)
TL;DR: In this paper, the authors present the first cosmological results based on Planck measurements of the cosmic microwave background (CMB) temperature and lensing-potential power spectra, which are extremely well described by the standard spatially-flat six-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations.
Abstract: This paper presents the first cosmological results based on Planck measurements of the cosmic microwave background (CMB) temperature and lensing-potential power spectra. We find that the Planck spectra at high multipoles (l ≳ 40) are extremely well described by the standard spatially-flat six-parameter ΛCDM cosmology with a power-law spectrum of adiabatic scalar perturbations. Within the context of this cosmology, the Planck data determine the cosmological parameters to high precision: the angular size of the sound horizon at recombination, the physical densities of baryons and cold dark matter, and the scalar spectral index are estimated to be θ∗ = (1.04147 ± 0.00062) × 10-2, Ωbh2 = 0.02205 ± 0.00028, Ωch2 = 0.1199 ± 0.0027, and ns = 0.9603 ± 0.0073, respectively(note that in this abstract we quote 68% errors on measured parameters and 95% upper limits on other parameters). For this cosmology, we find a low value of the Hubble constant, H0 = (67.3 ± 1.2) km s-1 Mpc-1, and a high value of the matter density parameter, Ωm = 0.315 ± 0.017. These values are in tension with recent direct measurements of H0 and the magnitude-redshift relation for Type Ia supernovae, but are in excellent agreement with geometrical constraints from baryon acoustic oscillation (BAO) surveys. Including curvature, we find that the Universe is consistent with spatial flatness to percent level precision using Planck CMB data alone. We use high-resolution CMB data together with Planck to provide greater control on extragalactic foreground components in an investigation of extensions to the six-parameter ΛCDM model. We present selected results from a large grid of cosmological models, using a range of additional astrophysical data sets in addition to Planck and high-resolution CMB data. None of these models are favoured over the standard six-parameter ΛCDM cosmology. The deviation of the scalar spectral index from unity isinsensitive to the addition of tensor modes and to changes in the matter content of the Universe. We find an upper limit of r0.002< 0.11 on the tensor-to-scalar ratio. There is no evidence for additional neutrino-like relativistic particles beyond the three families of neutrinos in the standard model. Using BAO and CMB data, we find Neff = 3.30 ± 0.27 for the effective number of relativistic degrees of freedom, and an upper limit of 0.23 eV for the sum of neutrino masses. Our results are in excellent agreement with big bang nucleosynthesis and the standard value of Neff = 3.046. We find no evidence for dynamical dark energy; using BAO and CMB data, the dark energy equation of state parameter is constrained to be w = -1.13-0.10+0.13. We also use the Planck data to set limits on a possible variation of the fine-structure constant, dark matter annihilation and primordial magnetic fields. Despite the success of the six-parameter ΛCDM model in describing the Planck data at high multipoles, we note that this cosmology does not provide a good fit to the temperature power spectrum at low multipoles. The unusual shape of the spectrum in the multipole range 20 ≲ l ≲ 40 was seen previously in the WMAP data and is a real feature of the primordial CMB anisotropies. The poor fit to the spectrum at low multipoles is not of decisive significance, but is an “anomaly” in an otherwise self-consistent analysis of the Planck temperature data.

7,060 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present the first results based on Planck measurements of the CMB temperature and lensing-potential power spectra, which are extremely well described by the standard spatially-flat six-parameter LCDM cosmology.
Abstract: We present the first results based on Planck measurements of the CMB temperature and lensing-potential power spectra. The Planck spectra at high multipoles are extremely well described by the standard spatially-flat six-parameter LCDM cosmology. In this model Planck data determine the cosmological parameters to high precision. We find a low value of the Hubble constant, H0=67.3+/-1.2 km/s/Mpc and a high value of the matter density parameter, Omega_m=0.315+/-0.017 (+/-1 sigma errors) in excellent agreement with constraints from baryon acoustic oscillation (BAO) surveys. Including curvature, we find that the Universe is consistent with spatial flatness to percent-level precision using Planck CMB data alone. We present results from an analysis of extensions to the standard cosmology, using astrophysical data sets in addition to Planck and high-resolution CMB data. None of these models are favoured significantly over standard LCDM. The deviation of the scalar spectral index from unity is insensitive to the addition of tensor modes and to changes in the matter content of the Universe. We find a 95% upper limit of r<0.11 on the tensor-to-scalar ratio. There is no evidence for additional neutrino-like relativistic particles. Using BAO and CMB data, we find N_eff=3.30+/-0.27 for the effective number of relativistic degrees of freedom, and an upper limit of 0.23 eV for the summed neutrino mass. Our results are in excellent agreement with big bang nucleosynthesis and the standard value of N_eff=3.046. We find no evidence for dynamical dark energy. Despite the success of the standard LCDM model, this cosmology does not provide a good fit to the CMB power spectrum at low multipoles, as noted previously by the WMAP team. While not of decisive significance, this is an anomaly in an otherwise self-consistent analysis of the Planck temperature data.

6,201 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