11. 
 Aghanim, N., et al.
(författare)

Planck 2018 results I. Overview and the cosmological legacy of Planck
 2020

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 641

Tidskriftsartikel (refereegranskat)abstract
 The European Space Agency's Planck satellite, which was 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, producing deep, highresolution, allsky maps in nine frequency bands from 30 to 857 GHz. This paper presents the cosmological legacy of Planck, which currently provides our strongest constraints on the parameters of the standard cosmological model and some of the tightest limits available on deviations from that model. The 6parameter Lambda CDM model continues to provide an excellent fit to the cosmic microwave background data at high and low redshift, describing the cosmological information in over a billion map pixels with just six parameters. With 18 peaks in the temperature and polarization angular power spectra constrained well, Planck measures five of the six parameters to better than 1% (simultaneously), with the bestdetermined parameter (theta (*)) now known to 0.03%. We describe the multicomponent sky as seen by Planck, the success of the Lambda CDM model, and the connection to lowerredshift probes of structure formation. We also give a comprehensive summary of the major changes introduced in this 2018 release. The Planck data, alone and in combination with other probes, provide stringent constraints on our models of the early Universe and the largescale structure within which all astrophysical objects form and evolve. We discuss some lessons learned from the Planck mission, and highlight areas ripe for further experimental advances.


12. 
 Adam, R., et al.
(författare)

Planck 2015 results IX. Diffuse component separation : CMB maps
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 594

Tidskriftsartikel (refereegranskat)abstract
 We present foregroundreduced cosmic microwave background (CMB) maps derived from the full Planck data set in both temperature and polarization. Compared to the corresponding Planck 2013 temperature sky maps, the total data volume is larger by a factor of 3.2 for frequencies between 30 and 70 GHz, and by 1.9 for frequencies between 100 and 857 GHz. In addition, systematic errors in the forms of temperaturetopolarization leakage, analoguetodigital conversion uncertainties, and very long time constant errors have been dramatically reduced, to the extent that the cosmological polarization signal may now be robustly recovered on angular scales l greater than or similar to 40. On the very largest scales, instrumental systematic residuals are still nonnegligible compared to the expected cosmological signal, and modes with l < 20 are accordingly suppressed in the current polarization maps by highpass filtering. As in 2013, four different CMB component separation algorithms are applied to these observations, providing a measure of stability with respect to algorithmic and modelling choices. The resulting polarization maps have rms instrumental noise ranging between 0.21 and 0.27 mu K averaged over 55' pixels, and between 4.5 and 6.1 mu K averaged over 3.'4 pixels. The cosmological parameters derived from the analysis of temperature power spectra are in agreement at the 1 sigma level with the Planck 2015 likelihood. Unresolved mismatches between the noise properties of the data and simulations prevent a satisfactory description of the higherorder statistical properties of the polarization maps. Thus, the primary applications of these polarization maps are those that do not require massive simulations for accurate estimation of uncertainties, for instance estimation of crossspectra and crosscorrelations, or stacking analyses. However, the amplitude of primordial nonGaussianity is consistent with zero within 2 sigma for all local, equilateral, and orthogonal configurations of the bispectrum, including for polarization Emodes. Moreover, excellent agreement is found regarding the lensing Bmode power spectrum, both internally among the various component separation codes and with the bestfit Planck 2015 Lambda cold dark matter model.


13. 
 Ade, P. A. R., et al.
(författare)

Planck 2015 results XVIII. Background geometry and topology of the Universe
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 594

Tidskriftsartikel (refereegranskat)abstract
 Maps of cosmic microwave background (CMB) temperature and polarization from the 2015 release of Planck data provide the highest quality fullsky view of the surface of last scattering available to date. This enables us to detect possible departures from a globally isotropic cosmology. We present the first searches using CMB polarization for correlations induced by a possible nontrivial topology with a fundamental domain that intersects, or nearly intersects, the lastscattering surface (at comoving distance chi(rec)), both via a direct scan for matched circular patterns at the intersections and by an optimal likelihood calculation for specific topologies. We specialize to flat spaces with cubic toroidal (T3) and slab (T1) topologies, finding that explicit searches for the latter are sensitive to other topologies with antipodal symmetry. These searches yield no detection of a compact topology with a scale below the diameter of the lastscattering surface. The limits on the radius Ri of the largest sphere inscribed in the fundamental domain (at loglikelihood ratio Delta ln L > 5 relative to a simplyconnected flat Planck bestfit model) are: Ri > 0.97 chi(rec) for the T3 cubic torus; and Ri > 0.56 chi(rec) for the T1 slab. The limit for the T3 cubic torus from the matchedcircles search is numerically equivalent, Ri > 0.97 chi(rec) at 99% confidence level from polarization data alone. We also perform a Bayesian search for an anisotropic global Bianchi VIIh geometry. In the nonphysical setting, where the Bianchi cosmology is decoupled from the standard cosmology, Planck temperature data favour the inclusion of a Bianchi component with a Bayes factor of at least 2.3 units of logevidence. However, the cosmological parameters that generate this pattern are in strong disagreement with those found from CMB anisotropy data alone. Fitting the induced polarization pattern for this model to the Planck data requires an amplitude of 0.10 +/ 0.04 compared to the value of + 1 if the model were to be correct. In the physically motivated setting, where the Bianchi parameters are coupled and fitted simultaneously with the standard cosmological parameters, we find no evidence for a Bianchi VIIh cosmology and constrain the vorticity of such models to (omega/H)(0) < 7.6 x 10(10) (95% CL).


14. 
 Aghanim, N., et al.
(författare)

Planck 2015 results XI. CMB power spectra, likelihoods, and robustness of parameters
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 594

Tidskriftsartikel (refereegranskat)abstract
 This paper presents the Planck 2015 likelihoods, statistical descriptions of the 2point 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 pixelbased likelihood at low multipoles (l < 30) and a Gaussian approximation to the distribution of crosspower 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 smallscale 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 endtoend simulations of the instrumental response to the sky, which were fed into the actual data processing pipeline; this does not reveal biases from residual lowlevel instrumental systematics. Even with the increase in precision and robustness, the Lambda CDM 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 5 sigma 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 Lambda CDM cosmology this requires tau = 0.078 +/ 0.019 for the reionization optical depth, which is significantly lower than estimates without the use of highfrequency data for explicit monitoring of dust emission. At high multipoles we detect residual systematic errors in E polarization, typically at the mu K2 level; we therefore choose to retain temperature information alone for high multipoles as the recommended baseline, in particular for testing nonminimal models. Nevertheless, the highmultipole polarization spectra from Planck are already good enough to enable a separate highprecision determination of the parameters of the Lambda CDM model, showing consistency with those established independently from temperature information alone.


15. 
 Aghanim, N., et al.
(författare)

Planck 2018 results VI. Cosmological parameters
 2020

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 641

Tidskriftsartikel (refereegranskat)abstract
 We present cosmological parameter results from the final fullmission 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 largescale 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 smallscale polarization leads to more robust constraints on many parameters, with residual modelling uncertainties estimated to affect them only at the 0.5 sigma level. We find good consistency with the standard spatiallyflat 6parameter Lambda CDM cosmology having a powerlaw 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 +/ 0.001, baryon density Omega (b)h(2)=0.0224 +/ 0.0001, scalar spectral index n(s)=0.965 +/ 0.004, and optical depth tau =0.054 +/ 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 +/ 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 baseLambda CDM cosmology, the inferred (modeldependent) lateUniverse parameters are: Hubble constant H0=(67.4 +/ 0.5) km s(1) Mpc(1); matter density parameter Omega (m)=0.315 +/ 0.007; and matter fluctuation amplitude sigma (8)=0.811 +/ 0.006. We find no compelling evidence for extensions to the baseLambda CDM model. Combining with baryon acoustic oscillation (BAO) measurements (and considering singleparameter extensions) we constrain the effective extra relativistic degrees of freedom to be Neff=2.99 +/ 0.17, in agreement with the Standard Model prediction Neff=3.046, and find that the neutrino mass is tightly constrained to Sigma m(nu)< 0.12 eV. The CMB spectra continue to prefer higher lensing amplitudes than predicted in base CDM at over 2 sigma, which pulls some parameters that affect the lensing amplitude away from the Lambda CDM model; however, this is not supported by the lensing reconstruction or (in models that also change the background geometry) BAO data. The joint constraint with BAO measurements on spatial curvature is consistent with a flat universe, Omega (K)=0.001 +/ 0.002. Also combining with Type Ia supernovae (SNe), the darkenergy equation of state parameter is measured to be w(0)=1.03 +/ 0.03, consistent with a cosmological constant. We find no evidence for deviations from a purely powerlaw primordial spectrum, and combining with data from BAO, BICEP2, and Keck Array data, we place a limit on the tensortoscalar ratio r(0.002)< 0.06. Standard bigbang nucleosynthesis predictions for the helium and deuterium abundances for the baseCDM cosmology are in excellent agreement with observations. The Planck baseLambda CDM results are in good agreement with BAO, SNe, and some galaxy lensing observations, but in slight tension with the Dark Energy Survey's combinedprobe results including galaxy clustering (which prefers lower fluctuation amplitudes or matter density parameters), and in significant, 3.6 sigma, 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.


16. 
 Ade, P. A. R., et al.
(författare)

Planck intermediate results XL. The SunyaevZeldovich signal from the Virgo cluster
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 596

Tidskriftsartikel (refereegranskat)abstract
 The Virgo cluster is the largest SunyaevZeldovich (SZ) source in the sky, both in terms of angular size and total integrated flux. Planck's wide angular scale and frequency coverage, together with its high sensitivity, enable a detailed study of this big object through the SZ effect. Virgo is well resolved by Planck, showing an elongated structure that correlates well with the morphology observed from Xrays, but extends beyond the observed Xray signal. We find good agreement between the SZ signal (or Compton parameter, y(c)) observed by Planck and the expected signal inferred from Xray observations and simple analytical models. Owing to its proximity to us, the gas beyond the virial radius in Virgo can be studied with unprecedented sensitivity by integrating the SZ signal over tens of square degrees. We study the signal in the outskirts of Virgo and compare it with analytical models and a constrained simulation of the environment of Virgo. Planck data suggest that significant amounts of lowdensity plasma surround Virgo, out to twice the virial radius. We find the SZ signal in the outskirts of Virgo to be consistent with a simple model that extrapolates the inferred pressure at lower radii, while assuming that the temperature stays in the keV range beyond the virial radius. The observed signal is also consistent with simulations and points to a shallow pressure profile in the outskirts of the cluster. This reservoir of gas at large radii can be linked with the hottest phase of the elusive warm/hot intergalactic medium. Taking the lack of symmetry of Virgo into account, we find that a prolate model is favoured by the combination of SZ and Xray data, in agreement with predictions. Finally, based on the combination of the same SZ and Xray data, we constrain the total amount of gas in Virgo. Under the hypothesis that the abundance of baryons in Virgo is representative of the cosmic average, we also infer a distance for Virgo of approximately 18 Mpc, in good agreement with previous estimates.


17. 
 Adam, R., et al.
(författare)

Planck intermediate results XLII. Largescale Galactic magnetic fields
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 596

Tidskriftsartikel (refereegranskat)abstract
 Recent models for the largescale Galactic magnetic fields in the literature have been largely constrained by synchrotron emission and Faraday rotation measures. We use three different but representative models to compare their predicted polarized synchrotron and dust emission with that measured by the Planck satellite. We first update these models to match the Planck synchrotron products using a common model for the cosmicray leptons. We discuss the impact on this analysis of the ongoing problems of component separation in the Planck microwave bands and of the uncertain cosmicray spectrum. In particular, the inferred degree of ordering in the magnetic fields is sensitive to these systematic uncertainties, and we further show the importance of considering the expected variations in the observables in addition to their mean morphology. We then compare the resulting simulated emission to the observed dust polarization and find that the dust predictions do not match the morphology in the Planck data but underpredict the dust polarization away from the plane. We modify one of the models to roughly match both observables at high latitudes by increasing the field ordering in the thin disc near the observer. Though this specific analysis is dependent on the component separation issues, we present the improved model as a proof of concept for how these studies can be advanced in future using complementary information from ongoing and planned observational projects.


18. 
 Ade, P. A. R., et al.
(författare)

Planck intermediate results XXXIX. The Planck list of highredshift source candidates
 2016

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 596

Tidskriftsartikel (refereegranskat)abstract
 The Planck mission, thanks to its large frequency range and allsky coverage, has a unique potential for systematically detecting the brightest, and rarest, submillimetre sources on the sky, including distant objects in the highredshift Universe traced by their dust emission. A novel method, based on a componentseparation procedure using a combination of Planck and IRAS data, has been validated and characterized on numerous simulations, and applied to select the most luminous cold submillimetre sources with spectral energy distributions peaking between 353 and 857 GHz at 5' resolution. A total of 2151 Planck highz source candidates (the PHZ) have been detected in the cleanest 26% of the sky, with flux density at 545 GHz above 500 mJy. Embedded in the cosmic infrared background close to the confusion limit, these highz candidates exhibit colder colours than their surroundings, consistent with redshifts z > 2, assuming a dust temperature of Txgal = 35K and a spectral index of beta(xgal) = 1.5. Exhibiting extremely high luminosities, larger than 10(14) Lcircle dot, the PHZ objects may be made of multiple galaxies or clumps at high redshift, as suggested by a first statistical analysis based on a comparison with number count models. Furthermore, first followup observations obtained from optical to submillimetre wavelengths, which can be found in companion papers, have confirmed that this list consists of two distinct populations. A small fraction (around 3%) of the sources have been identified as strongly gravitationally lensed starforming galaxies at redshift 2 to 4, while the vast majority of the PHZ sources appear as overdensities of dusty starforming galaxies, having colours consistent with being at z > 2, and may be considered as protocluster candidates. The PHZ provides an original sample, which is complementary to the Planck SunyaevZeldovich Catalogue (PSZ2); by extending the population of virialized massive galaxy clusters detected below z < 1.5 through their SZ signal to a population of sources at z > 1.5, the PHZ may contain the progenitors of today's clusters. Hence the Planck list of highredshift source candidates opens a new window on the study of the early stages of structure formation, particularly understanding the intensively starforming phase at highz.


19. 
 Delabrouille, J., et al.
(författare)

Exploring cosmic origins with CORE : Survey requirements and mission design
 2018

Ingår i: Journal of Cosmology and Astroparticle Physics.  : IOP Publishing.  14757516. ; :4

Tidskriftsartikel (refereegranskat)abstract
 Future observations of cosmic microwave background (CMB) polarisation have the potential to answer some of the most fundamental questions of modern physics and cosmology, including: what physical process gave birth to the Universe we see today? What are the dark matter and dark energy that seem to constitute 95% of the energy density of the Universe? Do we need extensions to the standard model of particle physics and fundamental interactions? Is the ACDM cosmological scenario correct, or are we missing an essential piece of the puzzle? In this paper, we list the requirements for a future CMB polarisation survey addressing these scientific objectives, and discuss the design drivers of the CORE space mission proposed to ESA in answer to the M5 call for a mediumsized mission. The rationale and options, and the methodologies used to assess the mission's performance, are of interest to other future CMB mission design studies. CORE has 19 frequency channels, distributed over a broad frequency range, spanning the 60600 GHz interval, to control astrophysical foreground emission. The angular resolution ranges from 2' to 18', and the aggregate CMB sensitivity is about 2 mu K.arcmin. The observations are made with a single integrated focalplane instrument, consisting of an array of 2100 cryogenicallycooled, linearlypolarised detectors at the focus of a 1.2m aperture crossDragone telescope. The mission is designed to minimise all sources of systematic effects, which must be controlled so that no more than 10(4) of the intensity leaks into polarisation maps, and no more than about 1% of Etype polarisation leaks into Btype modes. CORE observes the sky from a large Lissajous orbit around the SunEarth L2 point on an orbit that offers stable observing conditions and avoids contamination from sidelobe pickup of stray radiation originating from the Sun, Earth, and Moon. The entire sky is observed repeatedly during four years of continuous scanning, with a combination of three rotations of the spacecraft over different timescales. With about 50% of the sky covered every few days, this scan strategy provides the mitigation of systematic effects and the internal redundancy that are needed to convincingly extract the primordial Bmode signal on large angular scales, and check with adequate sensitivity the consistency of the observations in several independent data subsets. CORE is designed as a nearultimate CMB polarisation mission which, for optimal complementarity with groundbased observations, will perform the observations that are known to be essential to CMB polarisation science and cannot be obtained by any other means than a dedicated space mission. It will provide wellcharacterised, highlyredundant multifrequency observations of polarisation at all the scales where foreground emission and cosmic variance dominate the final uncertainty for obtaining precision CMB science, as well as 2' angular resolution maps of highfrequency foreground emission in the 300600 GHz frequency range, essential for complementarity with future groundbased observations with large telescopes that can observe the CMB with the same beamsize.


20. 
 Aghanim, N., et al.
(författare)

Planck 2018 results V. CMB power spectra and likelihoods
 2020

Ingår i: Astronomy and Astrophysics.  : EDP Sciences.  00046361 . 14320746. ; 641

Tidskriftsartikel (refereegranskat)abstract
 We describe the legacy Planck cosmic microwave background (CMB) likelihoods derived from the 2018 data release. The overall approach is similar in spirit to the one retained for the 2013 and 2015 data release, with a hybrid method using different approximations at low (l< 30) and high (l >= 30) multipoles, implementing several methodological and dataanalysis refinements compared to previous releases. With more realistic simulations, and better correction and modelling of systematic effects, we can now make full use of the CMB polarization observed in the High Frequency Instrument (HFI) channels. The lowmultipole EE crossspectra from the 100 GHz and 143 GHz data give a constraint on the Lambda CDM reionization opticaldepth parameter tau to better than 15% (in combination with the TT lowl data and the highl temperature and polarization data), tightening constraints on all parameters with posterior distributions correlated with tau. We also update the weaker constraint on tau from the joint TEB likelihood using the Low Frequency Instrument (LFI) channels, which was used in 2015 as part of our baseline analysis. At higher multipoles, the CMB temperature spectrum and likelihood are very similar to previous releases. A better model of the temperaturetopolarization leakage and corrections for the effective calibrations of the polarization channels (i.e., the polarization efficiencies) allow us to make full use of polarization spectra, improving the Lambda CDM constraints on the parameters theta(MC), omega(c), omega(b), and H0 by more than 30%, and n(s) by more than 20% compared to TTonly constraints. Extensive tests on the robustness of the modelling of the polarization data demonstrate good consistency, with some residual modelling uncertainties. At high multipoles, we are now limited mainly by the accuracy of the polarization efficiency modelling. Using our various tests, simulations, and comparison between different highmultipole likelihood implementations, we estimate the consistency of the results to be better than the 0.5 sigma level on the Lambda CDM parameters, as well as classical singleparameter extensions for the joint likelihood (to be compared to the 0.3 sigma levels we achieved in 2015 for the temperature data alone on Lambda CDM only). Minor curiosities already present in the previous releases remain, such as the differences between the bestfit Lambda CDM parameters for the l< 800 and l> 800 ranges of the power spectrum, or the preference for more smoothing of the powerspectrum peaks than predicted in Lambda CDM fits. These are shown to be driven by the temperature power spectrum and are not significantly modified by the inclusion of the polarization data. Overall, the legacy Planck CMB likelihoods provide a robust tool for constraining the cosmological model and represent a reference for future CMB observations.

