1. 
 Ade, P. A. R., et al.
(författare)

Planck 2015 results XX. Constraints on inflation
 2016

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

Tidskriftsartikel (refereegranskat)abstract
 We present the implications for cosmic inflation of the Planck measurements of the cosmic microwave background (CMB) anisotropies in both temperature and polarization based on the full Planck survey, which includes more than twice the integration time of the nominal survey used for the 2013 release papers. The Planck full mission temperature data and a first release of polarization data on large angular scales measure the spectral index of curvature perturbations to be n(s) = 0.968 +/ 0.006 and tightly constrain its scale dependence to dn(s)/dln k = 0.003 +/ 0.007 when combined with the Planck lensing likelihood. When the Planck highl polarization data are included, the results are consistent and uncertainties are further reduced. The upper bound on the tensortoscalar ratio is r(0).(002) < 0.11 (95% CL). This upper limit is consistent with the Bmode polarization constraint r < 0.12 (95% CL) obtained from a joint analysis of the BICEP2/Keck Array and Planck data. These results imply that V(phi) proportional to phi(2) and natural inflation are now disfavoured compared to models predicting a smaller tensortoscalar ratio, such as R2 inflation. We search for several physically motivated deviations from a simple powerlaw spectrum of curvature perturbations, including those motivated by a reconstruction of the inflaton potential not relying on the slowroll approximation. We find that such models are not preferred, either according to a Bayesian model comparison or according to a frequentist simulationbased analysis. Three independent methods reconstructing the primordial power spectrum consistently recover a featureless and smooth PR (k) over the range of scales 0.008 Mpc(1) less than or similar to k less than or similar to 0.1 Mpc(1). At large scales, each method finds deviations from a power law, connected to a deficit at multipoles l approximate to 2040 in the temperature power spectrum, but at an uncompelling statistical significance owing to the large cosmic variance present at these multipoles. By combining power spectrum and nonGaussianity bounds, we constrain models with generalized Lagrangians, including Galileon models and axion monodromy models. The Planck data are consistent with adiabatic primordial perturbations, and the estimated values for the parameters of the base Lambda cold dark matter (Lambda CDM) model are not significantly altered when more general initial conditions are admitted. In correlated mixed adiabatic and isocurvature models, the 95% CL upper bound for the nonadiabatic contribution to the observed CMB temperature variance is vertical bar alpha(nonadi)vertical bar < 1.9%, 4.0%, and 2.9% for CDM, neutrino density, and neutrino velocity isocurvature modes, respectively. We have tested inflationary models producing an anisotropic modulation of the primordial curvature power spectrum finding that the dipolar modulation in the CMB temperature field induced by a CDM isocurvature perturbation is not preferred at a statistically significant level. We also establish tight constraints on a possible quadrupolar modulation of the curvature perturbation. These results are consistent with the Planck 2013 analysis based on the nominal mission data and further constrain slowroll singlefield inflationary models, as expected from the increased precision of Planck data using the full set of observations.


2. 
 Ade, P. A. R., et al.
(författare)

Planck 2015 results XVII. Constraints on primordial nonGaussianity
 2016

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

Tidskriftsartikel (refereegranskat)abstract
 The Planck full mission cosmic microwave background (CMB) temperature and Emode polarization maps are analysed to obtain constraints on primordial nonGaussianity (NG). Using three classes of optimal bispectrum estimators  separable templatefitting (KSW), binned, and modal we obtain consistent values for the primordial local, equilateral, and orthogonal bispectrum amplitudes, quoting as our final result from temperature alone f(NL)(local) = 2.5 +/ 5.7, f(NL)(equil) = 16 +/ 70, and f(NL)(ortho) = 34 +/ 33 (68% CL, statistical). Combining temperature and polarization data we obtain f(NL)(local) = 0.8 +/ 5.0, f(NL)(equil) = 4 +/ 43, and f(NL)(ortho) = 26 +/ 21 (68% CL, statistical). The results are based on comprehensive crossvalidation of these estimators on Gaussian and nonGaussian simulations, are stable across component separation techniques, pass an extensive suite of tests, and are consistent with estimators based on measuring the Minkowski functionals of the CMB. The effect of timedomain deglitching systematics on the bispectrum is negligible. In spite of these test outcomes we conservatively label the results including polarization data as preliminary, owing to a known mismatch of the noise model in simulations and the data. Beyond estimates of individual shape amplitudes, we present modelindependent, threedimensional reconstructions of the Planck CMB bispectrum and derive constraints on early universe scenarios that generate primordial NG, including general singlefield models of inflation, axion inflation, initial state modifications, models producing parityviolating tensor bispectra, and directionally dependent vector models. We present a wide survey of scaledependent feature and resonance models, accounting for the look elsewhere effect in estimating the statistical significance of features. We also look for isocurvature NG, and find no signal, but we obtain constraints that improve significantly with the inclusion of polarization. The primordial trispectrum amplitude in the local model is constrained to be g(NL)(local) = (9.0 +/ 7.7) x 10(4) (68% CL statistical), and we perform an analysis of trispectrum shapes beyond the local case. The global picture that emerges is one of consistency with the premises of the Lambda CDM cosmology, namely that the structure we observe today was sourced by adiabatic, passive, Gaussian, and primordial seed perturbations.


3. 
 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.


4. 
 Akrami, Y., et al.
(författare)

Planck 2018 results X. Constraints on inflation
 2020

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

Tidskriftsartikel (refereegranskat)abstract
 We report on the implications for cosmic inflation of the 2018 release of the Planck cosmic microwave background (CMB) anisotropy measurements. The results are fully consistent with those reported using the data from the two previous Planck cosmological releases, but have smaller uncertainties thanks to improvements in the characterization of polarization at low and high multipoles. Planck temperature, polarization, and lensing data determine the spectral index of scalar perturbations to be n(s)=0.9649 +/ 0.0042 at 68% CL. We find no evidence for a scale dependence of n(s), either as a running or as a running of the running. The Universe is found to be consistent with spatial flatness with a precision of 0.4% at 95% CL by combining Planck with a compilation of baryon acoustic oscillation data. The Planck 95% CL upper limit on the tensortoscalar ratio, r(0.002)< 0.10, is further tightened by combining with the BICEP2/Keck Array BK15 data to obtain r(0.002)< 0.056. In the framework of standard singlefield inflationary models with Einstein gravity, these results imply that: (a) the predictions of slowroll models with a concave potential, V(phi) < 0, are increasingly favoured by the data; and (b) based on two different methods for reconstructing the inflaton potential, we find no evidence for dynamics beyond slow roll. Three different methods for the nonparametric reconstruction of the primordial power spectrum consistently confirm a pure power law in the range of comoving scales 0.005 Mpc(1)k less than or similar to 0.2 Mpc(1). A complementary analysis also finds no evidence for theoretically motivated parameterized features in the Planck power spectra. For the case of oscillatory features that are logarithmic or linear in k, this result is further strengthened by a new combined analysis including the Planck bispectrum data. The new Planck polarization data provide a stringent test of the adiabaticity of the initial conditions for the cosmological fluctuations. In correlated, mixed adiabatic and isocurvature models, the nonadiabatic contribution to the observed CMB temperature variance is constrained to 1.3%, 1.7%, and 1.7% at 95% CL for cold dark matter, neutrino density, and neutrino velocity, respectively. Planck power spectra plus lensing set constraints on the amplitude of compensated cold dark matterbaryon isocurvature perturbations that are consistent with current complementary measurements. The polarization data also provide improved constraints on inflationary models that predict a small statistically anisotropic quadupolar modulation of the primordial fluctuations. However, the polarization data do not support physical models for a scaledependent dipolar modulation. All these findings support the key predictions of the standard singlefield inflationary models, which will be further tested by future cosmological observations.


5. 
 Akrami, Y., et al.
(författare)

Planck 2018 results IX. Constraints on primordial nonGaussianity
 2020

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

Tidskriftsartikel (refereegranskat)abstract
 We analyse the Planck fullmission cosmic microwave background (CMB) temperature and Emode polarization maps to obtain constraints on primordial nonGaussianity (NG). We compare estimates obtained from separable templatefitting, binned, and optimal modal bispectrum estimators, finding consistent values for the local, equilateral, and orthogonal bispectrum amplitudes. Our combined temperature and polarization analysis produces the following final results: (local)(NL) = 0.9 +/ 5.1 f NL local =  0.9 +/ 5.1 ; f(NL)(equil) = 26 +/ 47 f NL equil =  26 +/ 47 ; and f(NL)(ortho) = 38 +/ 24 f NL ortho =  38 +/ 24 (68% CL, statistical). These results include lowmultipole (4 <= l< 40) polarization data that are not included in our previous analysis. The results also pass an extensive battery of tests (with additional tests regarding foreground residuals compared to 2015), and they are stable with respect to our 2015 measurements (with small fluctuations, at the level of a fraction of a standard deviation, which is consistent with changes in data processing). Polarizationonly bispectra display a significant improvement in robustness; they can now be used independently to set primordial NG constraints with a sensitivity comparable to WMAP temperaturebased results and they give excellent agreement. In addition to the analysis of the standard local, equilateral, and orthogonal bispectrum shapes, we consider a large number of additional cases, such as scaledependent feature and resonance bispectra, isocurvature primordial NG, and paritybreaking models, where we also place tight constraints but do not detect any signal. The nonprimordial lensing bispectrum is, however, detected with an improved significance compared to 2015, excluding the null hypothesis at 3.5. Beyond estimates of individual shape amplitudes, we also present modelindependent reconstructions and analyses of the Planck CMB bispectrum. Our final constraint on the local primordial trispectrum shape is g(NL)(local) = (5.8 +/ 6.5) x 10(4) g NL local = (  5.8 +/ 6.5 ) x 10 4 (68% CL, statistical), while constraints for other trispectrum shapes are also determined. Exploiting the tight limits on various bispectrum and trispectrum shapes, we constrain the parameter space of different earlyUniverse scenarios that generate primordial NG, including general singlefield models of inflation, multifield models (e.g. curvaton models), models of inflation with axion fields producing parityviolation bispectra in the tensor sector, and inflationary models involving vectorlike fields with directionallydependent bispectra. Our results provide a highprecision test for structureformation scenarios, showing complete agreement with the basic picture of the Lambda CDM cosmology regarding the statistics of the initial conditions, with cosmic structures arising from adiabatic, passive, Gaussian, and primordial seed perturbations.


6. 
 Ade, Peter, et al.
(författare)

The Simons Observatory : science goals and forecasts
 2019

Ingår i: Journal of Cosmology and Astroparticle Physics.  : IOP Publishing.  14757516. ; :2

Tidskriftsartikel (refereegranskat)abstract
 The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations in the early 2020s. We describe the scientific goals of the experiment, motivate the design, and forecast its performance. SO will measure the temperature and polarization anisotropy of the cosmic microwave background in six frequency bands centered at: 27, 39, 93, 145, 225 and 280 GHz. The initial con figuration of SO will have three smallaperture 0.5m telescopes and one largeaperture 6m telescope, with a total of 60,000 cryogenic bolometers. Our key science goals are to characterize the primordial perturbations, measure the number of relativistic species and the mass of neutrinos, test for deviations from a cosmological constant, improve our understanding of galaxy evolution, and constrain the duration of reionization. The small aperture telescopes will target the largest angular scales observable from Chile, mapping approximate to 10% of the sky to a white noise level of 2 mu Karcmin in combined 93 and 145 GHz bands, to measure the primordial tensortoscalar ratio, r, at a target level of sigma(r) = 0.003. The large aperture telescope will map approximate to 40% of the sky at arcminute angular resolution to an expected white noise level of 6 mu Karcmin in combined 93 and 145 GHz bands, overlapping with the majority of the Large Synoptic Survey Telescope sky region and partially with the Dark Energy Spectroscopic Instrument. With up to an order of magnitude lower polarization noise than maps from the Planck satellite, the highresolution sky maps will constrain cosmological parameters derived from the damping tail, gravitational lensing of the microwave background, the primordial bispectrum, and the thermal and kinematic SunyaevZel'dovich effects, and will aid in delensing the largeangle polarization signal to measure the tensortoscalar ratio. The survey will also provide a legacy catalog of 16,000 galaxy clusters and more than 20,000 extragalactic sources.

