Planck 2018 results Aghanim, N.; Akrami, Y.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
We present measurements of the cosmic microwave background (CMB) lensing potential using the final
Planck
2018 temperature and polarization data. Using polarization maps filtered to account for the ...noise anisotropy, we increase the significance of the detection of lensing in the polarization maps from 5
σ
to 9
σ
. Combined with temperature, lensing is detected at 40
σ
. We present an extensive set of tests of the robustness of the lensing-potential power spectrum, and construct a minimum-variance estimator likelihood over lensing multipoles 8 ≤
L
≤ 400 (extending the range to lower
L
compared to 2015), which we use to constrain cosmological parameters. We find good consistency between lensing constraints and the results from the
Planck
CMB power spectra within the ΛCDM model. Combined with baryon density and other weak priors, the lensing analysis alone constrains
σ
8
Ω
m
0.25
= 0.589 ± 0.020 (1
σ
errors). Also combining with baryon acoustic oscillation data, we find tight individual parameter constraints,
σ
8
= 0.811 ± 0.019,
H
0
= 67.9
−1.3
+1.2
km s
−1
Mpc
−1
, and Ω
m
= 0.303
−0.018
+0.016
. Combining with
Planck
CMB power spectrum data, we measure
σ
8
to better than 1% precision, finding
σ
8
= 0.811 ± 0.006. CMB lensing reconstruction data are complementary to galaxy lensing data at lower redshift, having a different degeneracy direction in
σ
8
− Ω
m
space; we find consistency with the lensing results from the Dark Energy Survey, and give combined lensing-only parameter constraints that are tighter than joint results using galaxy clustering. Using the
Planck
cosmic infrared background (CIB) maps as an additional tracer of high-redshift matter, we make a combined
Planck
-only estimate of the lensing potential over 60% of the sky with considerably more small-scale signal. We additionally demonstrate delensing of the
Planck
power spectra using the joint and individual lensing potential estimates, detecting a maximum removal of 40% of the lensing-induced power in all spectra. The improvement in the sharpening of the acoustic peaks by including both CIB and the quadratic lensing reconstruction is detected at high significance.
Planck 2018 results Aghanim, N.; Akrami, Y.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
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 data-analysis 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 low-multipole
EE
cross-spectra from the 100 GHz and 143 GHz data give a constraint on the ΛCDM reionization optical-depth parameter
τ
to better than 15% (in combination with the
TT
low-
ℓ
data and the high-
ℓ
temperature and polarization data), tightening constraints on all parameters with posterior distributions correlated with
τ
. We also update the weaker constraint on
τ
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 temperature-to-polarization 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 ΛCDM constraints on the parameters
θ
MC
,
ω
c
,
ω
b
, and
H
0
by more than 30%, and n
s
by more than 20% compared to TT-only 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 high-multipole likelihood implementations, we estimate the consistency of the results to be better than the 0.5
σ
level on the ΛCDM parameters, as well as classical single-parameter extensions for the joint likelihood (to be compared to the 0.3
σ
levels we achieved in 2015 for the temperature data alone on ΛCDM only). Minor curiosities already present in the previous releases remain, such as the differences between the best-fit ΛCDM parameters for the
ℓ
< 800 and
ℓ
> 800 ranges of the power spectrum, or the preference for more smoothing of the power-spectrum peaks than predicted in ΛCDM 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.
Planck 2018 results Akrami, Y.; Aumont, J.; Baccigalupi, C. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
We analyse the
Planck
full-mission cosmic microwave background (CMB) temperature and
E
-mode polarization maps to obtain constraints on primordial non-Gaussianity (NG). We compare estimates obtained ...from separable template-fitting, 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:
f
NL
local
= −0.9 ± 5.1;
f
NL
equil
= −26 ± 47; and
f
NL
ortho
= −38 ± 24 (68% CL, statistical). These results include low-multipole (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). Polarization-only bispectra display a significant improvement in robustness; they can now be used independently to set primordial NG constraints with a sensitivity comparable to WMAP temperature-based 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 scale-dependent feature and resonance bispectra, isocurvature primordial NG, and parity-breaking models, where we also place tight constraints but do not detect any signal. The non-primordial lensing bispectrum is, however, detected with an improved significance compared to 2015, excluding the null hypothesis at 3.5
σ
. Beyond estimates of individual shape amplitudes, we also present model-independent 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) × 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 early-Universe scenarios that generate primordial NG, including general single-field models of inflation, multi-field models (e.g. curvaton models), models of inflation with axion fields producing parity-violation bispectra in the tensor sector, and inflationary models involving vector-like fields with directionally-dependent bispectra. Our results provide a high-precision test for structure-formation scenarios, showing complete agreement with the basic picture of the ΛCDM cosmology regarding the statistics of the initial conditions, with cosmic structures arising from adiabatic, passive, Gaussian, and primordial seed perturbations.
Planck 2018 results Akrami, Y.; Ashdown, M.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
Analysis of the
Planck
2018 data set indicates that the statistical properties of the cosmic microwave background (CMB) temperature anisotropies are in excellent agreement with previous studies using ...the 2013 and 2015 data releases. In particular, they are consistent with the Gaussian predictions of the ΛCDM cosmological model, yet also confirm the presence of several so-called “anomalies” on large angular scales. The novelty of the current study, however, lies in being a first attempt at a comprehensive analysis of the statistics of the polarization signal over all angular scales, using either maps of the Stokes parameters,
Q
and
U
, or the
E
-mode signal derived from these using a new methodology (which we describe in an appendix). Although remarkable progress has been made in reducing the systematic effects that contaminated the 2015 polarization maps on large angular scales, it is still the case that residual systematics (and our ability to simulate them) can limit some tests of non-Gaussianity and isotropy. However, a detailed set of null tests applied to the maps indicates that these issues do not dominate the analysis on intermediate and large angular scales (i.e.,
ℓ
≲ 400). In this regime, no unambiguous detections of cosmological non-Gaussianity, or of anomalies corresponding to those seen in temperature, are claimed. Notably, the stacking of CMB polarization signals centred on the positions of temperature hot and cold spots exhibits excellent agreement with the ΛCDM cosmological model, and also gives a clear indication of how
Planck
provides state-of-the-art measurements of CMB temperature and polarization on degree scales.
Planck 2018 results Akrami, Y.; Ashdown, M.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
We present full-sky maps of the cosmic microwave background (CMB) and polarized synchrotron and thermal dust emission, derived from the third set of
Planck
frequency maps. These products have ...significantly lower contamination from instrumental systematic effects than previous versions. The methodologies used to derive these maps follow closely those described in earlier papers, adopting four methods (
Commander
,
NILC
,
SEVEM
, and
SMICA
) to extract the CMB component, as well as three methods (
Commander
,
GNILC
, and
SMICA
) to extract astrophysical components. Our revised CMB temperature maps agree with corresponding products in the
Planck
2015 delivery, whereas the polarization maps exhibit significantly lower large-scale power, reflecting the improved data processing described in companion papers; however, the noise properties of the resulting data products are complicated, and the best available end-to-end simulations exhibit relative biases with respect to the data at the few percent level. Using these maps, we are for the first time able to fit the spectral index of thermal dust independently over 3° regions. We derive a conservative estimate of the mean spectral index of polarized thermal dust emission of
β
d
= 1.55 ± 0.05, where the uncertainty marginalizes both over all known systematic uncertainties and different estimation techniques. For polarized synchrotron emission, we find a mean spectral index of
β
s
= −3.1 ± 0.1, consistent with previously reported measurements. We note that the current data processing does not allow for construction of unbiased single-bolometer maps, and this limits our ability to extract CO emission and correlated components. The foreground results for intensity derived in this paper therefore do not supersede corresponding
Planck
2015 products. For polarization the new results supersede the corresponding 2015 products in all respects.
Planck intermediate results Aghanim, N; Ashdown, M; Aumont, J ...
Astronomy and astrophysics (Berlin),
12/2016, Letnik:
596
Journal Article
Recenzirano
Odprti dostop
This paper describes the identification, modelling, and removal of previously unexplained systematic effects in the polarization data of the Planck High Frequency Instrument (HFI) on large angular ...scales, including new mapmaking and calibration procedures, new and more complete end-to-end simulations, and a set of robust internal consistency checks on the resulting maps. These maps, at 100, 143, 217, and 353GHz, are early versions of those that will be released in final form later in 2016. The improvements allow us to determine the cosmic reionization optical depth tau using, for the first time, the low-multipole EE data from HFI, reducing significantly the central value and uncertainty, and hence the upper limit. Two different likelihood procedures are used to constrain tau from two estimators of the CMB E- and B-mode angular power spectra at 100 and 143GHz, after debiasing the spectra from a small remaining systematic contamination. These all give fully consistent results. A further consistency test is performed using cross-correlations derived from the Low Frequency Instrument maps of the Planck 2015 data release and the new HFI data. For this purpose, end-to-end analyses of systematic effects from the two instruments are used to demonstrate the near independence of their dominant systematic error residuals. The tightest result comes from the HFI-based tau posterior distribution using the maximum likelihood power spectrum estimator from EE data only, giving a value 0.055 + or - 0.009. In a companion paper these results are discussed in the context of the best-fit PlanckLambdaCDM cosmological model and recent models of reionization.
Planck intermediate results Akrami, Y.; Andersen, K. J.; Baccigalupi, C. ...
Astronomy and astrophysics (Berlin),
11/2020, Letnik:
643
Journal Article
Recenzirano
Odprti dostop
We present the
NPIPE
processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the
Planck
Low Frequency Instrument (LFI) and High Frequency ...Instrument (HFI) using high-performance computers.
NPIPE
represents a natural evolution of previous
Planck
analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 processing procedure,
NPIPE
uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly,
NPIPE
employs the HFI 2018 time-domain processing methodology to correct for bandpass mismatch at all frequencies. In addition,
NPIPE
introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0′.9 pixels (
N
side
= 4096), ensuring that the full angular information in the data is represented in the maps even at the highest
Planck
resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the
NPIPE
maps, we present the first estimate of the Solar dipole determined through component separation across all nine
Planck
frequencies. The amplitude is (3366.6 ± 2.7)
μ
K, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of
τ
= 0.051 ± 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a
Planck
first, these simulations include full time-domain processing of the beam-convolved CMB anisotropies. The release of
NPIPE
maps and simulations is accompanied with a complete suite of raw and processed time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations.
Planck 2018 results Akrami, Y.; Ashdown, M.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
The study of polarized dust emission has become entwined with the analysis of the cosmic microwave background (CMB) polarization in the quest for the curl-like
B
-mode polarization from primordial ...gravitational waves and the low-multipole
E
-mode polarization associated with the reionization of the Universe. We used the new
Planck
PR3 maps to characterize Galactic dust emission at high latitudes as a foreground to the CMB polarization and use end-to-end simulations to compute uncertainties and assess the statistical significance of our measurements. We present
Planck
EE
,
BB
, and
TE
power spectra of dust polarization at 353 GHz for a set of six nested high-Galactic-latitude sky regions covering from 24 to 71% of the sky. We present power-law fits to the angular power spectra, yielding evidence for statistically significant variations of the exponents over sky regions and a difference between the values for the
EE
and
BB
spectra, which for the largest sky region are
α
E
E
= −2.42 ± 0.02 and
α
B
B
= −2.54 ± 0.02, respectively. The spectra show that the
TE
correlation and
E/B
power asymmetry discovered by
Planck
extend to low multipoles that were not included in earlier
Planck
polarization papers due to residual data systematics. We also report evidence for a positive
TB
dust signal. Combining data from
Planck
and WMAP, we have determined the amplitudes and spectral energy distributions (SEDs) of polarized foregrounds, including the correlation between dust and synchrotron polarized emission, for the six sky regions as a function of multipole. This quantifies the challenge of the component-separation procedure that is required for measuring the low-
ℓ
reionization CMB
E
-mode signal and detecting the reionization and recombination peaks of primordial CMB
B
modes. The SED of polarized dust emission is fit well by a single-temperature modified black-body emission law from 353 GHz to below 70 GHz. For a dust temperature of 19.6 K, the mean dust spectral index for dust polarization is
β
d
P
= 1.53±0.02. The difference between indices for polarization and total intensity is
β
d
P
−
β
d
I
= 0.05±0.03. By fitting multi-frequency cross-spectra between
Planck
data at 100, 143, 217, and 353 GHz, we examine the correlation of the dust polarization maps across frequency. We find no evidence for a loss of correlation and provide lower limits to the correlation ratio that are tighter than values we derive from the correlation of the 217- and 353 GHz maps alone. If the
Planck
limit on decorrelation for the largest sky region applies to the smaller sky regions observed by sub-orbital experiments, then frequency decorrelation of dust polarization might not be a problem for CMB experiments aiming at a primordial
B
-mode detection limit on the tensor-to-scalar ratio
r
≃ 0.01 at the recombination peak. However, the
Planck
sensitivity precludes identifying how difficult the component-separation problem will be for more ambitious experiments targeting lower limits on
r
.
Planck 2018 results Aghanim, N.; Akrami, Y.; Ashdown, M. ...
Astronomy and astrophysics (Berlin),
09/2020, Letnik:
641
Journal Article
Recenzirano
Odprti dostop
Observations of the submillimetre emission from Galactic dust, in both total intensity
I
and polarization, have received tremendous interest thanks to the
Planck
full-sky maps. In this paper we make ...use of such full-sky maps of dust polarized emission produced from the third public release of
Planck
data. As the basis for expanding on astrophysical studies of the polarized thermal emission from Galactic dust, we present full-sky maps of the dust polarization fraction
p
, polarization angle
ψ
, and dispersion function of polarization angles . The joint distribution (one-point statistics) of
p
and
N
H
confirms that the mean and maximum polarization fractions decrease with increasing
N
H
. The uncertainty on the maximum observed polarization fraction,
p
max
= 22.0
−1.4
+3.5
% at 353 GHz and 80′ resolution, is dominated by the uncertainty on the Galactic emission zero level in total intensity, in particular towards diffuse lines of sight at high Galactic latitudes. Furthermore, the inverse behaviour between
p
and found earlier is seen to be present at high latitudes. This follows the ∝
p
−1
relationship expected from models of the polarized sky (including numerical simulations of magnetohydrodynamical turbulence) that include effects from only the topology of the turbulent magnetic field, but otherwise have uniform alignment and dust properties. Thus, the statistical properties of
p
,
ψ
, and for the most part reflect the structure of the Galactic magnetic field. Nevertheless, we search for potential signatures of varying grain alignment and dust properties. First, we analyse the product map ×
p
, looking for residual trends. While the polarization fraction
p
decreases by a factor of 3−4 between
N
H
= 10
20
cm
−2
and
N
H
= 2 × 10
22
cm
−2
, out of the Galactic plane, this product ×
p
only decreases by about 25%. Because is independent of the grain alignment efficiency, this demonstrates that the systematic decrease in
p
with
N
H
is determined mostly by the magnetic-field structure and not by a drop in grain alignment. This systematic trend is observed both in the diffuse interstellar medium (ISM) and in molecular clouds of the Gould Belt. Second, we look for a dependence of polarization properties on the dust temperature, as we would expect from the radiative alignment torque (RAT) theory. We find no systematic trend of ×
p
with the dust temperature
T
d
, whether in the diffuse ISM or in the molecular clouds of the Gould Belt. In the diffuse ISM, lines of sight with high polarization fraction
p
and low polarization angle dispersion tend, on the contrary, to have colder dust than lines of sight with low
p
and high . We also compare the
Planck
thermal dust polarization with starlight polarization data in the visible at high Galactic latitudes. The agreement in polarization angles is remarkable, and is consistent with what we expect from the noise and the observed dispersion of polarization angles in the visible on the scale of the
Planck
beam. The two polarization emission-to-extinction ratios,
R
P
/
p
and
R
S/V
, which primarily characterize dust optical properties, have only a weak dependence on the column density, and converge towards the values previously determined for translucent lines of sight. We also determine an upper limit for the polarization fraction in extinction,
p
V
/
E
(
B
−
V
), of 13% at high Galactic latitude, compatible with the polarization fraction
p
≈ 20% observed at 353 GHz. Taken together, these results provide strong constraints for models of Galactic dust in diffuse gas.
Planck intermediate results Aghanim, N.; Akrami, Y.; Aumont, J. ...
Astronomy and astrophysics (Berlin),
2017, Letnik:
607
Journal Article
Recenzirano
Odprti dostop
The six parameters of the standard ΛCDM model have best-fit values derived from the
Planck
temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These ...shifts are driven by features in the
Planck
temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium
τ
, the baryon density
ω
b
, the matter density
ω
m
, the angular size of the sound horizon
θ
∗
, the spectral index of the primordial power spectrum,
n
s
, and
A
s
e
− 2
τ
(where
A
s
is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment
ℓ
< 800 in the
Planck
temperature power spectrum) and an all angular-scale data set (
ℓ
< 2500
Planck
temperature power spectrum), each with a prior on
τ
of 0.07 ± 0.02. We find that the shifts, in units of the 1
σ
expected dispersion for each parameter, are { Δ
τ,
Δ
A
s
e
− 2
τ
,Δ
n
s
,Δ
ω
m
,Δ
ω
b
,Δ
θ
∗
} = { −1.7,−2.2,1.2,−2.0,1.1,0.9 }, with a
χ
2
value of 8.0. We find that this
χ
2
value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2
σ
in 9% of simulated data sets, meaning that the shifts are not unusually large. Comparing
ℓ
< 800 instead to
ℓ
> 800, or splitting at a different multipole, yields similar results. We examined the
ℓ
< 800 model residuals in the
ℓ
> 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in ΛCDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is
τ
, which, at fixed
A
s
e
− 2
τ
, affects the
ℓ
> 800 temperature power spectrum solely through the associated change in
A
s
and the impact of that on the lensing potential power spectrum. We also ask, “what is it about the power spectrum at
ℓ
< 800 that leads to somewhat different best-fit parameters than come from the full
ℓ
range?” We find that if we discard the data at
ℓ
< 30, where there is a roughly 2
σ
downward fluctuation in power relative to the model that best fits the full
ℓ
range, the
ℓ
< 800 best-fit parameters shift significantly towards the
ℓ
< 2500 best-fit parameters. In contrast, including
ℓ
< 30, this previously noted “low-
ℓ
deficit” drives
n
s
up and impacts parameters correlated with
n
s
, such as
ω
m
and
H
0
. As expected, the
ℓ
< 30 data have a much greater impact on the
ℓ
< 800 best fit than on the
ℓ
< 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-
ℓ
residuals and the deficit in low-
ℓ
power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between
Planck
TT
data and two other CMB data sets, namely the
Planck
lensing reconstruction and the
TT
power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the ΛCDM model.
PDF