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1

Cai, Rong-Gen, Zong-Kuan Guo, and Bo Tang. "Updated reduced CMB data and constraints on cosmological parameters." International Journal of Modern Physics D 24, no. 10 (August 12, 2015): 1550071. http://dx.doi.org/10.1142/s0218271815500716.

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Анотація:
We obtain the reduced CMB data {lA, R, z∗} from WMAP9, WMAP9+BKP, Planck+WP and Planck+WP+BKP for the ΛCDM and wCDM models with or without spatial curvature. We then use these reduced CMB data in combination with low-redshift observations to put constraints on cosmological parameters. We find that including BKP results in a higher value of the Hubble constant especially when the equation of state (EOS) of dark energy and curvature are allowed to vary. For the ΛCDM model with curvature, the estimate of the Hubble constant with Planck+WP+Lensing is inconsistent with the one derived from Planck+WP+BKP at about 1.2σ confidence level (CL).
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2

Mangilli, Anna. "From data to science: Planck data and the CMB non-Gaussianity." Proceedings of the International Astronomical Union 10, S306 (May 2014): 131–34. http://dx.doi.org/10.1017/s1743921314013465.

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AbstractStudying the non-Gaussianity (NG) of the Cosmic Microwave Background (CMB) is an extremely powerful tool to investigate the properties of the very early Universe. The Planck nominal mission CMB maps yielded unprecedented constraints on primordial non-Gaussianity providing with the highest precision test of the standard model of inflation. Planck's high sensitivity also allowed to find evidence for the first time of the late-time non-Gaussianity arising from the Lensing-Integrated Sachs Wolfe (ISW) cross correlation. In this talk I will give details on the Planck data analysis and I will discuss the theoretical implications of the results.
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3

Partridge, Bruce. "Planck on Extragalactic Radio Sources: Data and Findings." Proceedings of the International Astronomical Union 11, A29B (August 2015): 51–53. http://dx.doi.org/10.1017/s174392131600449x.

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AbstractPlanck scanned the entire sky every six months at nine frequencies bands from 28 to 857 GHz with enough sensitivity to detect over a thousand radio sources. It thus provided measurements of the mm and sub-mm spectra of these sources in a regular cadence, even at wavelengths hard to observe from the ground. Polarization measurements (or upper limits) are provided for brighter sources at 28-353 GHz. Finally, Planck is calibrated to <1% accuracy in most of its frequency bands. I briefly introduce the valuable data set Planck provides on extragalactic sources, then describe some of the scientific conclusions drawn from the Planck measurements.
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4

Streblyanska, A., R. Barrena, J. A. Rubiño-Martín, R. F. J. van der Burg, N. Aghanim, A. Aguado-Barahona, A. Ferragamo, and H. Lietzen. "Characterization of a subsample of the Planck SZ source cluster catalogues using optical SDSS DR12 data." Astronomy & Astrophysics 617 (September 2018): A71. http://dx.doi.org/10.1051/0004-6361/201732306.

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Aims. The Planck catalogues of Sunyaev –Zeldovich (SZ) sources, PSZ1 and PSZ2, are the largest catalogues of galaxy clusters selected through their SZ signature in the full sky. In 2013, we started a long-term observational programme at Canary Island observatories with the aim of validating ∼500 unconfirmed SZ sources. In this work we present results of the initial pre-screening of possible cluster counterparts using photometric and spectroscopic data of the Sloan Digital Sky Survey DR12. Our main aim is to identify previously unconfirmed PSZ2 cluster candidates and to contribute in the determination of the actual purity and completeness of Planck SZ source sample. Methods. Using the latest version of the PSZ2 catalogue, we selected all sources overlapping with the SDSS DR12 footprint and without redshift information. We validated these cluster fields following optical criteria (mainly distance with respect to the Planck pointing, magnitude of the brightest cluster galaxy, and cluster richness), and combined these criteria with the profiles of the Planck Compton y-maps. This combined procedure allows for a more robust identification of optical counterparts compared to simply cross-matching with existing SDSS cluster catalogues that have been constructed from earlier SDSS data releases. Results. The sample contains new redshifts for 37 Planck galaxy clusters that were not included in the original release of PSZ2 Planck catalogue. We detect three cases as possible multiple counterparts. We show that a combination of all available information (optical images and profile of SZ signal) can provide correct associations between the observed Planck SZ source and the optically identified cluster. We also show that Planck SZ detection is very sensitive even to high-z (z > 0.5) clusters. In addition, we also present updated spectroscopic information for 34 Planck PSZ1 sources (33 previously photometrically confirmed and 1 new identification).
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5

Csáki, Csaba, Nemanja Kaloper, and John Terning. "Planck data and ultralight axions." Journal of Cosmology and Astroparticle Physics 2015, no. 06 (June 23, 2015): 041. http://dx.doi.org/10.1088/1475-7516/2015/06/041.

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6

Pagano, L., J. M. Delouis, S. Mottet, J. L. Puget, and L. Vibert. "Reionization optical depth determination from Planck HFI data with ten percent accuracy." Astronomy & Astrophysics 635 (March 2020): A99. http://dx.doi.org/10.1051/0004-6361/201936630.

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We present an estimation of the reionization optical depth τ from an improved analysis of data from the High Frequency Instrument (HFI) on board the Planck satellite. By using an improved version of the HFI map-making code, we greatly reduce the residual large-scale contamination affecting the data, characterised in, but not fully removed from, the Planck 2018 legacy release. This brings the dipole distortion systematic effect, contaminating the very low multipoles, below the noise level. On large-scale polarization-only data, we measure τ = 0.0566−0.0062+0.0053 at 68% C.L., reducing the Planck 2018 legacy release uncertainty by ∼40%. Within the ΛCDM model, in combination with the Planck large-scale temperature likelihood, and the high-ℓ temperature and polarization likelihood, we measure τ = 0.059 ± 0.006 at 68% C.L., which corresponds to a mid-point reionization redshift of zre = 8.14 ± 0.61 at 68% C.L. This estimation of the reionization optical depth with 10% accuracy is the strongest constraint to date.
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7

Ruiz-Granda, M., and P. Vielva. "Constraining CMB physical processes using Planck 2018 data." Journal of Cosmology and Astroparticle Physics 2022, no. 11 (November 1, 2022): 043. http://dx.doi.org/10.1088/1475-7516/2022/11/043.

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Abstract This paper aims to perform a phenomenological parametrisation of the standard cosmological model, ΛCDM, to weigh the different physical processes that define the pattern of the angular power spectra of the Cosmic Microwave Background (CMB) anisotropies. We use six phenomenological amplitudes to account for the Sachs-Wolfe, early and late Integrated Sachs-Wolfe, polarization contribution, Doppler and lensing effects. To do so, we have adapted the CLASS Boltzmann code and used the Markov Chain Monte Carlo (MCMC) sampler of Cobaya to explore the Planck 2018 likelihood to constrain different combinations of cosmological and phenomenological parameters. Observing deviations of the mean values of the phenomenological amplitudes from the predictions of the ΛCDM model could be useful to resolve existing cosmological tensions. For the first time, a comprehensive analysis of the physical processes of the CMB has been performed using the Planck 2018 temperature, polarization and lensing power spectra. In a previous work, the phenomenological amplitudes were constrained using only the TT data, however, by including the polarization and lensing data we find that the constraints on these physical contributions are tighter. In addition, some degeneracies that appear only when considering TT data are completely broken by taking into account all Planck 2018 data. Consequently, models with more than three phenomenological amplitudes can be studied, which is prohibitive when only the temperature power spectrum is used. The results presented in this paper show that the Planck experiment can constrain all phenomenological amplitudes except the late Integrated Sachs-Wolfe effect. No inconsistencies were found with the ΛCDM model, and the largest improvements were obtained for the models that include the lensing parameter, AL .
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8

Maris, Michele, Erik Romelli, Maurizio Tomasi, Anna Gregorio, Maura Sandri, Samuele Galeotta, Daniele Tavagnacco, Marco Frailis, Gianmarco Maggio, and Andrea Zacchei. "Revised planet brightness temperatures using the Planck/LFI 2018 data release." Astronomy & Astrophysics 647 (March 2021): A104. http://dx.doi.org/10.1051/0004-6361/202037788.

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Aims. We present new estimates of the brightness temperatures of Jupiter, Saturn, Uranus, and Neptune based on the measurements carried in 2009–2013 by Planck/LFI at 30, 44, and 70 GHz and released to the public in 2018. This work extends the results presented in the 2013 and 2015 Planck/LFI Calibration Papers, based on the data acquired in 2009–2011. Methods. Planck observed each planet up to eight times during the nominal mission. We processed time-ordered data from the 22 LFI radiometers to derive planet antenna temperatures for each planet and transit. We accounted for the beam shape, radiometer bandpasses, and several systematic effects. We compared our results with the results from the ninth year of WMAP, Planck/HFI observations, and existing data and models for planetary microwave emissivity. Results. For Jupiter, we obtain Tb = 144.9, 159.8, 170.5 K (± 0.2 K at 1σ, with temperatures expressed using the Rayleigh-Jeans scale) at 30, 44 and 70 GHz, respectively, or equivalently a band averaged Planck temperature Tb(ba) = 144.7, 160.3, 171.2 K in good agreement with WMAP and existing models. A slight excess at 30 GHz with respect to models is interpreted as an effect of synchrotron emission. Our measures for Saturn agree with the results from WMAP for rings Tb = 9.2 ± 1.4, 12.6 ± 2.3, 16.2 ± 0.8 K, while for the disc we obtain Tb = 140.0 ± 1.4, 147.2 ± 1.2, 150.2 ± 0.4 K, or equivalently a Tb(ba) = 139.7, 147.8, 151.0 K. Our measures for Uranus (Tb = 152 ± 6, 145 ± 3, 132.0 ± 2 K, or Tb(ba) = 152, 145, 133 K) and Neptune (Tb = 154 ± 11, 148 ± 9, 128 ± 3 K, or Tb(ba) = 154, 149, 128 K) agree closely with WMAP and previous data in literature.
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9

Nunes, Rafael C., Santosh K. Yadav, J. F. Jesus, and Armando Bernui. "Cosmological parameter analyses using transversal BAO data." Monthly Notices of the Royal Astronomical Society 497, no. 2 (July 11, 2020): 2133–41. http://dx.doi.org/10.1093/mnras/staa2036.

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ABSTRACT We investigate observational constraints on cosmological parameters combining 15 measurements of the transversal BAO scale (obtained free of any fiducial cosmology) with Planck–CMB data to explore the parametric space of some cosmological models. We investigate how much Planck + transversal BAO data can constraint the minimum Lambda cold dark matter (ΛCDM) model, and extensions, including neutrinos mass scale Mν, and the possibility for a dynamical dark energy (DE) scenario. Assuming the ΛCDM cosmology, we find H0 = 69.23 ± 0.50 km s−1 Mpc−1, Mν &lt; 0.11 eV, and rdrag = 147.59 ± 0.26 Mpc (the sound horizon at drag epoch) from Planck + transversal BAO data. When assuming a dynamical DE cosmology, we find that the inclusion of the BAO data can indeed break the degeneracy of the DE free parameters, improving the constraints on the full parameter space significantly. We note that the model is compatible with local measurements of H0 and there is no tension on H0 estimates in this dynamical DE context. Also, we discuss constraints and consequences from a joint analysis with the local H0 measurement from SH0ES. Finally, we perform a model-independent analysis for the deceleration parameter, q(z), using only information from transversal BAO data.
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10

Davidson, Aharon. "Holographic shell model: Stack data structure inside black holes?" International Journal of Modern Physics D 23, no. 05 (April 30, 2014): 1450041. http://dx.doi.org/10.1142/s0218271814500412.

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Rather than tiling the black hole horizon by Planck area patches, we suggest that bits of information inhabit, universally and holographically, the entire black core interior, a bit per a light sheet unit interval of order Planck area difference. The number of distinguishable (tagged by a binary code) configurations, counted within the context of a discrete holographic shell model, is given by the Catalan series. The area entropy formula is recovered, including Cardy's universal logarithmic correction, and the equipartition of mass per degree of freedom is proven. The black hole information storage resembles, in the count procedure, the so-called stack data structure.
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11

Akrami, Y., F. Arroja, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, et al. "Planck 2018 results." Astronomy & Astrophysics 641 (September 2020): A10. http://dx.doi.org/10.1051/0004-6361/201833887.

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Анотація:
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 ns = 0.9649 ± 0.0042 at 68% CL. We find no evidence for a scale dependence of ns, 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 tensor-to-scalar ratio, r0.002 < 0.10, is further tightened by combining with the BICEP2/Keck Array BK15 data to obtain r0.002 < 0.056. In the framework of standard single-field inflationary models with Einstein gravity, these results imply that: (a) the predictions of slow-roll models with a concave potential, V″(ϕ) < 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 non-parametric reconstruction of the primordial power spectrum consistently confirm a pure power law in the range of comoving scales 0.005 Mpc−1 ≲ k ≲ 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 non-adiabatic 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 matter-baryon 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 scale-dependent dipolar modulation. All these findings support the key predictions of the standard single-field inflationary models, which will be further tested by future cosmological observations.
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12

Huang, Qing-Guo, Ke Wang, and Sai Wang. "Distance priors from Planck 2015 data." Journal of Cosmology and Astroparticle Physics 2015, no. 12 (December 11, 2015): 022. http://dx.doi.org/10.1088/1475-7516/2015/12/022.

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13

Ashdown, M. A. J., C. Baccigalupi, A. Balbi, J. G. Bartlett, J. Borrill, C. Cantalupo, G. de Gasperis, et al. "Making sky maps from Planck data." Astronomy & Astrophysics 467, no. 2 (February 12, 2007): 761–75. http://dx.doi.org/10.1051/0004-6361:20065829.

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14

Tauber, Jan. "Planck team replies to data 'anomalies'." Nature 506, no. 7486 (February 2014): 34. http://dx.doi.org/10.1038/506034c.

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15

Calderon, Rodrigo, Arman Shafieloo, Dhiraj Kumar Hazra та Wuhyun Sohn. "On the consistency of ΛCDM with CMB measurements in light of the latest Planck, ACT and SPT data". Journal of Cosmology and Astroparticle Physics 2023, № 08 (1 серпня 2023): 059. http://dx.doi.org/10.1088/1475-7516/2023/08/059.

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Анотація:
Abstract Using Gaussian Processes we perform a thorough, non-parametric consistency test of the ΛCDM model when confronted with state-of-the-art TT, TE, and EE measurements of the anisotropies in the Cosmic Microwave Background by the Planck, ACT, and SPT collaborations. Using ΛCDM's best-fit predictions to the TTTEEE data from Planck, we find no statistically significant deviations when looking for signatures in the residuals across the different datasets. The results of SPT are in good agreement with the ΛCDM best-fit predictions to the Planck data, while the results of ACT are only marginally consistent. However, when using the best-fit predictions to CamSpec — a recent reanalysis of the Planck data — as the mean function, we find larger discrepancies between the datasets. Our analysis also reveals an interesting feature in the polarisation (EE) measurements from the CamSpec analysis, which could be explained by a slight underestimation of the covariance matrix. Interestingly, the disagreement between CamSpec and Planck/ACT is mainly visible in the residuals of the TT spectrum, the latter favoring a scale-invariant tilt ns ≃ 1, which is consistent with previous findings from parametric analyses. We also report some features in the EE measurements captured both by ACT and SPT which are independent of the chosen mean function and could be hinting towards a common physical origin. For completeness, we repeat our analysis using the best-fit spectra to ACT+WMAP as the mean function. Finally, we test the internal consistency of the Planck data alone by studying the high and low-ℓ ranges separately, finding no discrepancy between small and large angular scales.
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16

Rebouças, Marcelo J., and Armando Bernui. "Searching for non-Gaussianity in the Planck data." Proceedings of the International Astronomical Union 10, S306 (May 2014): 147–49. http://dx.doi.org/10.1017/s1743921314013829.

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AbstractThe statistical properties of the temperature anisotropies and polarization of the of cosmic microwave background (CMB) radiation offer a powerful probe of the physics of the early universe. In recent works a statistical procedure based upon the calculation of the kurtosis and skewness of the data in patches of CMB sky-sphere has been proposed and used to investigate the large-angle deviation from Gaussianity in WMAP maps. Here we briefly address the question as to how this analysis of Gaussianity is modified if the foreground-cleaned Planck maps are considered. We show that although the foreground-cleaned Planck maps present significant deviation from Gaussianity of different degrees when a less severe mask is used, they become consistent with Gaussianity, as detected by our indicators, when masked with the union mask U73.
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17

Di Valentino, Eleonora, and Sarah Bridle. "Exploring the Tension between Current Cosmic Microwave Background and Cosmic Shear Data." Symmetry 10, no. 11 (November 2, 2018): 585. http://dx.doi.org/10.3390/sym10110585.

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This paper provides a snapshot of the formal S 8 ≡ σ 8 Ω m / 0.3 tension between Planck 2015 and the Kilo Degree Survey of450 deg 2 of imaging data (KiDS-450) or the Canada France Hawaii Lensing Survey (CFHTLenS). We find that the Cosmic Microwave Bckground (CMB) and cosmic shear datasets are in tension in the standard Λ Cold Dark Matter ( Λ CDM) model, and that adding massive neutrinos does not relieve the tension. If we include an additional scaling parameter on the CMB lensing amplitude A l e n s , we find that this can put in agreement the Planck 2015 with the cosmic shear data. A l e n s is a phenomenological parameter that is found to be more than 2 σ higher than the expected value in the Planck 2015 data, suggesting an higher amount of lensing in the power spectra, not supported by the trispectrum analysis.
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18

Campeti, Paolo, and Eiichiro Komatsu. "New Constraint on the Tensor-to-scalar Ratio from the Planck and BICEP/Keck Array Data Using the Profile Likelihood." Astrophysical Journal 941, no. 2 (December 1, 2022): 110. http://dx.doi.org/10.3847/1538-4357/ac9ea3.

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Abstract Motivated by the discrepancy between Bayesian and frequentist upper limits on the tensor-to-scalar ratio parameter r found by the SPIDER collaboration, we investigate whether a similar trend is also present in the latest Planck and BICEP/Keck Array data. We derive a new upper bound on r using the frequentist profile likelihood method. We vary all the relevant cosmological parameters of the ΛCDM model, as well as the nuisance parameters. Unlike the Bayesian analysis using Markov Chain Monte Carlo (MCMC), our analysis is independent of the choice of priors. Using Planck Public Release 4, BICEP/Keck Array 2018, Planck cosmic microwave background lensing, and baryon acoustic oscillation data, we find an upper limit of r < 0.037 at 95% Confidence Level (C.L.), similar to the Bayesian MCMC result of r < 0.038 for a flat prior on r and a conditioned Planck lowlEB covariance matrix.
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19

Burenin, Rodion. "Cosmological constraints on matter density perturbations amplitude, neutrino mass and number of relativistic species." EPJ Web of Conferences 191 (2018): 01009. http://dx.doi.org/10.1051/epjconf/201819101009.

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Анотація:
It is shown that Planck CMB temperature anisotropy data at high multipoles, ℓ > 1000, produce the measurement of matter density perturbations amplitude that contradict to all other constraints obtained both from remaining Planck CMB anisotropy data and from other cosmological data, at about 3:7σ significance level. With the exception of Planck CMB temperature anisotropy data at high multipoles, all other measurements of density perturbation amplitude are in good agreement between each other and give the following measurements of linear density perturbation amplitude: σ8 = 0:792 ± 0:006, mean density of the Universe: Ωm = 0:287 ± 0:007, and Hubble constant: H0 = 69:4 ± 0:6 km s-1 Mpc-1. Therefore, in this case the tensions in H0 constraints between Planck+BAO data and direct H0 measurements are weaken, and the tensions in σ8 measurements between Planck CMB data and large scale structure data disappear completely. Taking in account the data on baryon acoustic oscillations and (or) direct measurements of the Hubble constant, one can obtain different constraints on sum of neutrino mass and number of relativistic species.
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20

Lemos, P., M. Raveri, A. Campos, Y. Park, C. Chang, N. Weaverdyck, D. Huterer, et al. "Assessing tension metrics with dark energy survey and Planck data." Monthly Notices of the Royal Astronomical Society 505, no. 4 (June 14, 2021): 6179–94. http://dx.doi.org/10.1093/mnras/stab1670.

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ABSTRACT Quantifying tensions – inconsistencies amongst measurements of cosmological parameters by different experiments – has emerged as a crucial part of modern cosmological data analysis. Statistically significant tensions between two experiments or cosmological probes may indicate new physics extending beyond the standard cosmological model and need to be promptly identified. We apply several tension estimators proposed in the literature to the dark energy survey (DES) large-scale structure measurement and Planck cosmic microwave background data. We first evaluate the responsiveness of these metrics to an input tension artificially introduced between the two, using synthetic DES data. We then apply the metrics to the comparison of Planck and actual DES Year 1 data. We find that the parameter differences, Eigentension, and Suspiciousness metrics all yield similar results on both simulated and real data, while the Bayes ratio is inconsistent with the rest due to its dependence on the prior volume. Using these metrics, we calculate the tension between DES Year 1 3 × 2pt and Planck, finding the surveys to be in ∼2.3σ tension under the ΛCDM paradigm. This suite of metrics provides a toolset for robustly testing tensions in the DES Year 3 data and beyond.
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21

Khokhlov, Dmitri L. "Planck Neutrinos as Ultra High Energy Cosmic Rays." Open Astronomy 29, no. 1 (June 24, 2020): 40–46. http://dx.doi.org/10.1515/astro-2020-0005.

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AbstractThe studied conjecture is that ultra high energy cosmic rays (UHECRs) are hypothetical Planck neutrinos arising in the decay of the protons falling onto the gravastar. The proton is assumed to decay at the Planck scale into positron and four Planck neutrinos. The supermassive black holes inside active galactic nuclei, while interpreted as gravastars, are considered as UHECR sources. The scattering of the Planck neutrinos by the proton at the Planck scale is considered. The Planck neutrinos contribution to the CR events may explain the CR spectrum from 5 × 1018 eV to 1020 eV. The muon number in the Planck neutrinos-initiated shower is estimated to be larger by a factor of 3/2 in comparison with the standard model that is consistent with the observational data.
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22

Oppizzi, Filippo, Federico De Luca, Hervé Bourdin, and Pasquale Mazzotta. "Pressure profiles of distant Galaxy clusters with Planck-SPT data." EPJ Web of Conferences 257 (2022): 00035. http://dx.doi.org/10.1051/epjconf/202225700035.

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We present a full set of numerical tools to extract Galaxy Cluster pressure profiles from the joint analysis of Planck and South Pole Telescope (SPT) observations. Pressure profiles are powerful tracers of the thermodynamic properties and the internal structure of the clusters. Tracing the pressure over the cosmic times allows one to constraints the evolution of the cluster structure and the contribution of astrophysical phenomena. SPT and Planck are complementary to constrain the cluster structure at various spatial scales. The SPT cluster catalogue counts 677 cluster candidates up to redshift 1.7, it is a nearly mass-limited sample, an ideal benchmark to test cluster evolution. We developed a pipeline to first separate the cluster signal from the background and foreground components and then jointly fit a parametric profile model on a combination of Planck and SPT data. We validate our algorithm on a subsample of six clusters, common to the SPT and the CHEX-MATE catalogues, comparing the results with the profiles obtained from X-ray observations with XMM-Newton.
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23

Zahrotunisa, Siti, Projo Danoedoro, and Sanjiwana Arjasakusuma. "COMPARISON OF SPLIT WINDOWS ALGORITHM AND PLANCK METHODS FOR SURFACE TEMPERATURE ESTIMATION BASED ON REMOTE SENSING DATA IN SEMARANG." JURNAL GEOGRAFI 14, no. 1 (February 1, 2022): 11. http://dx.doi.org/10.24114/jg.v14i1.24603.

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Surface temperature is one of the parameters in land–surface physical processes and is applied to global warming, climate change, and cycle hydrology. Two thermal bands in Landsat 8 imagery can be used as input for surface temperature extraction using the Split Windows Algorithm (SWA) and Planck method. This study aims to compare surface temperature estimates using the SWA and Planck methods and determine the surface temperature distribution based on the condition of land cover and its changes. The remote sensing data used are Landsat-8 OLI/TIRS Aqua MODIS images on August 27, 2013, and October 1, 2020. The results showed that Landsat 8 could obtain land cover information with an accuracy of 90% in 2013 and 91% in 2020. Planck surface temperature in 2013 was 1-3°C higher than SWA, while in 2020, Planck was 0.001-0.05°C lower than SWA but had similar distribution and pattern. The vegetation in the study area's central and south sides has a lower surface temperature than the built-up area on the north side. Land cover changes from non-built up to build-up area cause surface temperatures to increase. Each land cover has a different emissivity value and affects the surface temperature value, i.e., the lower the emissivity, the higher the surface temperature. The emissivity with surface temperature has a pearson correlation value ≥-0.8**.Keywords: Surface Temperature, Split Windows Algorithm, Planck
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24

Aghanim, N., Y. Akrami, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, et al. "Planck 2018 results." Astronomy & Astrophysics 641 (September 2020): A8. http://dx.doi.org/10.1051/0004-6361/201833886.

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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 5σ to 9σ. Combined with temperature, lensing is detected at 40σ. 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 σ8Ωm0.25 = 0.589 ± 0.020 (1σ errors). Also combining with baryon acoustic oscillation data, we find tight individual parameter constraints, σ8 = 0.811 ± 0.019, H0 = 67.9−1.3+1.2 km s−1 Mpc−1, and Ωm = 0.303−0.018+0.016. Combining with Planck CMB power spectrum data, we measure σ8 to better than 1% precision, finding σ8 = 0.811 ± 0.006. CMB lensing reconstruction data are complementary to galaxy lensing data at lower redshift, having a different degeneracy direction in σ8 − Ωm 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.
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25

Rachen, Jörg P., Elina Keihänen, and Martin Reinecke. "Blind Search for Variability in Planck Data." Proceedings of the International Astronomical Union 11, A29B (August 2015): 62–63. http://dx.doi.org/10.1017/s1743921316004506.

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AbstractThe sky is full of variable and transient sources on all time scales, from milliseconds to decades. Planck's regular scanning strategy makes it an ideal instrument to search for variable sky signals in the millimetre and submillimetre regime, on time scales from hours to several years. A precondition is that instrumental noise and systematic effects, caused in particular by non-symmetric beam shapes, are properly removed. We present a method to perform a full sky blind search for variable and transient objects at all Planck frequencies.
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26

Ghrear, Majd, Emory F. Bunn, Dagoberto Contreras, and Douglas Scott. "Testing for directionality in the Planck polarization and lensing data." Monthly Notices of the Royal Astronomical Society 490, no. 3 (October 7, 2019): 3404–13. http://dx.doi.org/10.1093/mnras/stz2777.

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ABSTRACT In order to better analyse the polarization of the cosmic microwave background (CMB), which is dominated by emission from our Galaxy, we need tools that can detect residual foregrounds in cleaned CMB maps. Galactic foregrounds introduce statistical anisotropy and directionality to the polarization pseudo-vectors of the CMB, which can be investigated by using the $\mathcal {D}$ statistic of Bunn and Scott. This statistic is rapidly computable and capable of investigating a broad range of data products for directionality. We demonstrate the application of this statistic to detecting foregrounds in polarization maps by analysing the uncleaned Planck 2018 frequency maps. For the Planck 2018 CMB maps, we find no evidence for residual foreground contamination. In order to examine the sensitivity of the $\mathcal {D}$ statistic, we add a varying fraction of the polarized thermal dust and synchrotron foreground maps to the CMB maps and show the per cent-level foreground contamination that would be detected with 95 per cent confidence. We also demonstrate application of the $\mathcal {D}$ statistic to another data product by analysing the gradient of the minimum-variance CMB lensing potential map (i.e. the deflection angle) for directionality. We find no excess directionality in the lensing potential map when compared to the simulations provided by the Planck Collaboration.
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27

An, Rui, André A. Costa, Linfeng Xiao, Jiajun Zhang, and Bin Wang. "Testing a quintessence model with Yukawa interaction from cosmological observations and N-body simulations." Monthly Notices of the Royal Astronomical Society 489, no. 1 (July 25, 2019): 297–309. http://dx.doi.org/10.1093/mnras/stz2028.

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ABSTRACT We consider a quintessence model with Yukawa interaction between dark energy and dark matter and constrain this model by employing the recent cosmological data including the updated cosmic microwave background (CMB) measurements from Planck 2015, the weak gravitational lensing measurements from Kilo Degree Survey (KiDS), and redshift-space distortions. We find that an interaction in the dark sector is compatible with observations. The updated Planck data can significantly improve the constraints compared with the previous results from Planck 2013, while the KiDS data have less constraining power than Planck. The Yukawa interaction model is found to be moderately favoured by Planck and able to alleviate the discordance between weak lensing measurements and CMB measurements as previously inferred from the standard Lambda cold dark matter model. N-body simulations for Yukawa interaction model is also performed. We find that using the halo density profile is plausible to improve the constraints significantly in the future.
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28

Aghanim, N., Y. Akrami, F. Arroja, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, et al. "Planck 2018 results." Astronomy & Astrophysics 641 (September 2020): A1. http://dx.doi.org/10.1051/0004-6361/201833880.

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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, high-resolution, all-sky 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 6-parameter ΛCDM 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 best-determined parameter (θ*) now known to 0.03%. We describe the multi-component sky as seen by Planck, the success of the ΛCDM model, and the connection to lower-redshift 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 large-scale 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.
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29

Gubitosi, Giulia, and Luca Pagano. "Planck-scale sensitivity of CMB polarization data." Nuclear Physics B - Proceedings Supplements 194 (October 2009): 69–75. http://dx.doi.org/10.1016/j.nuclphysbps.2009.07.027.

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30

Bhat, Faizan, Mussadiq H. Qureshi, Manzoor A. Malik, and Asif Iqbal. "Complex geometry of space–time motivated by gravity’s rainbow." Canadian Journal of Physics 97, no. 5 (May 2019): 558–61. http://dx.doi.org/10.1139/cjp-2017-0352.

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In this paper, we generalize the formalism of gravity’s rainbow to complex space–time. The resulting geometry depends on the energy of the probe in such a way that the usual real manifold is the low energy approximation of the Planck scale geometry of space–time. So, our formalism agrees with all the observational data about our space–time being real, as at the scale these experiments are preformed, the imaginary part of the geometry is suppressed by Planck energy. However, the imaginary part of the geometry becomes important near the Planck energy, and so it cannot be neglected near the Planck scale. So, the Planck scale geometry of space–time is described by a complex manifold.
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31

Keihänen, E., V. Lindholm, M. Lopez-Caniego, M. Maris, M. Reinecke, M. Sandri, and A. S. Suur-Uski. "Beam-deconvolved Planck LFI maps." Astronomy & Astrophysics 632 (November 21, 2019): A1. http://dx.doi.org/10.1051/0004-6361/201935875.

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The Planck Collaboration made its final data release in 2018. In this paper we describe beam-deconvolution map products made from Planck Low Frequency Instrument (LFI) data using the artDeco deconvolution code to symmetrize the effective beam. The deconvolution results are auxiliary data products, available through the Planck Legacy Archive. Analysis of these deconvolved survey difference maps reveals signs of residual signal in the 30 GHz and 44 GHz frequency channels. We produce low-resolution maps and corresponding noise covariance matrices (NCVMs). The NCVMs agree reasonably well with the half-ring noise estimates except for 44 GHz, where we observe an asymmetry between EE and BB noise spectra, possibly a sign of further unresolved systematic error. In contrast to the official Planck LFI maps, the beam-deconvolution maps have not been corrected for bandpass mismatch, and the residual noise is not well approximated by white noise.
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32

Akrami, Y., K. J. Andersen, M. Ashdown, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, et al. "Planck intermediate results." Astronomy & Astrophysics 643 (November 2020): A42. http://dx.doi.org/10.1051/0004-6361/202038073.

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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 (Nside = 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) μK, 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.
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33

Channuie, Phongpichit. "BICEP2 constrains composite inflation." International Journal of Modern Physics D 23, no. 08 (July 2014): 1450070. http://dx.doi.org/10.1142/s0218271814500709.

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In light of BICEP2, we re-examine single field inflationary models in which the inflation is a composite state stemming from various four-dimensional strongly coupled theories. We study in the Einstein frame a set of cosmological parameters, the primordial spectral index ns and tensor-to-scalar ratio r, predicted by such models. We confront the predicted results with the joint Planck data, and with the recent BICEP2 data. We constrain the number of e-foldings for composite models of inflation in order to obtain a successful inflation. We find that the minimal composite inflationary model is fully consistent with the Planck data. However it is in tension with the recent BICEP2 data. The observables predicted by the glueball inflationary model can be consistent with both Planck and BICEP2 contours if a suitable number of e-foldings are chosen. Surprisingly, the super Yang–Mills inflationary prediction is significantly consistent with the Planck and BICEP2 observations.
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34

Akrami, Y., M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, et al. "Planck intermediate results." Astronomy & Astrophysics 607 (November 2017): A122. http://dx.doi.org/10.1051/0004-6361/201630311.

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Measurements of flux density are described for five planets, Mars, Jupiter, Saturn, Uranus, and Neptune, across the six Planck High Frequency Instrument frequency bands (100–857 GHz) and these are then compared with models and existing data. In our analysis, we have also included estimates of the brightness of Jupiter and Saturn at the three frequencies of the Planck Low Frequency Instrument (30, 44, and 70 GHz). The results provide constraints on the intrinsic brightness and the brightness time-variability of these planets. The majority of the planet flux density estimates are limited by systematic errors, but still yield better than 1% measurements in many cases. Applying data from Planck HFI, the Wilkinson Microwave Anisotropy Probe (WMAP), and the Atacama Cosmology Telescope (ACT) to a model that incorporates contributions from Saturn’s rings to the planet’s total flux density suggests a best fit value for the spectral index of Saturn’s ring system of βring = 2.30 ± 0.03 over the 30–1000 GHz frequency range. Estimates of the polarization amplitude of the planets have also been made in the four bands that have polarization-sensitive detectors (100–353 GHz); this analysis provides a 95% confidence level upper limit on Mars’s polarization of 1.8, 1.7, 1.2, and 1.7% at 100, 143, 217, and 353 GHz, respectively. The average ratio between the Planck-HFI measurements and the adopted model predictions for all five planets (excluding Jupiter observations for 353 GHz) is 1.004, 1.002, 1.021, and 1.033 for 100, 143, 217, and 353 GHz, respectively. Model predictions for planet thermodynamic temperatures are therefore consistent with the absolute calibration of Planck-HFI detectors at about the three-percent level. We compare our measurements with published results from recent cosmic microwave background experiments. In particular, we observe that the flux densities measured by Planck HFI and WMAP agree to within 2%. These results allow experiments operating in the mm-wavelength range to cross-calibrate against Planck and improve models of radiative transport used in planetary science.
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35

Regaldo-Saint Blancard, Bruno, Erwan Allys, François Boulanger, François Levrier, and Niall Jeffrey. "A new approach for the statistical denoising of Planck interstellar dust polarization data." Astronomy & Astrophysics 649 (May 2021): L18. http://dx.doi.org/10.1051/0004-6361/202140503.

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Dust emission is the main foreground for cosmic microwave background polarization. Its statistical characterization must be derived from the analysis of observational data because the precision required for a reliable component separation is far greater than what is currently achievable with physical models of the turbulent magnetized interstellar medium. This Letter takes a significant step toward this goal by proposing a method that retrieves non-Gaussian statistical characteristics of dust emission from noisy Planck polarization observations at 353 GHz. We devised a statistical denoising method based on wavelet phase harmonics (WPH) statistics, which characterize the coherent structures in non-Gaussian random fields and define a generative model of the data. The method was validated on mock data combining a dust map from a magnetohydrodynamic simulation and Planck noise maps. The denoised map reproduces the true power spectrum down to scales where the noise power is an order of magnitude larger than that of the signal. It remains highly correlated to the true emission and retrieves some of its non-Gaussian properties. Applied to Planck data, the method provides a new approach to building a generative model of dust polarization that will characterize the full complexity of the dust emission. We also release PyWPH, a public Python package, to perform GPU-accelerated WPH analyses on images.
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36

López-Caniego, Marcos. "The Planck Compact Source Catalogues: present and future." Proceedings of the International Astronomical Union 11, A29B (August 2015): 61. http://dx.doi.org/10.1017/s1743921316004476.

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AbstractThe Planck Collaboration has produced catalogues of radio and sub-millimeter compact sources at the nine Planck frequencies in total intensity and polarization. In particular, the 2015 Second Planck Catalogue of Compact Sources (PCCS2) contains over 45.000 sources detected in the Planck full mission maps. Since the Planck instruments have polarization capabilities in seven of its nine detectors, we were able to measure the polarized flux density of over 600 sources between 30 and 353 GHz. But we are searching not only for compact sources in single frequency maps, and we take advantage of the large frequency coverage of Planck to search for objects with specific emission laws. This is the case of the SZ catalogue of cluster of galaxies (PSZ2), that lists 1653 clusters, 1203 of which are confirmed clusters with clear associations in external data-sets, and the Galactic cold clump catalogue (PGCC) with 13188 objects. The Planck Collaboration has also published a list of high-redshift source candidates (see the report by Ludovic Montier here). These objects are rare bright sub-millimeter sources with an spectral energy distribution peaking between 353 and 857 GHz, and have been detected combining Planck and IRAS data. The colours of most of these objects are consistent with redshifts z>2, a fraction of which could be lensed objects with redshifts between 2 and 4.But new catalogues are foreseen. A multi-frequency compact source catalogue is being produced selecting sources at radio frequencies and studying them across all Planck bands. Multi-frequency catalogues can be difficult to produce in experiments like Planck that have a large frequency coverage and very different resolutions across bands. In some cases, a source can be very bright across the whole Planck frequency range and it is easy to do the associations across channels. However, it frequent to find unrelated sub-millimeter sources within the half-degree beam of the 30 GHz low frequency detector, and the association work must be done with great care. For this purpose, we are combining a multi-frequency detection procedure with a principal component analysis to produce the catalogue. In addition, for those sources where a clear identification can be made, we will attempt to include flux density information from Herschel and other experiments, in particular for those blazars that are bright in radio, sub-mm and even in gamma-ray frequencies, as seen by Fermi. Moreover, Planck has made available to the community the single survey frequency maps that allow astronomers to study the long-term variability of their favourite sources. New functionalities will be also added to the Planck Legacy Archive†, for example a timeline-cutting tool that will allow one to produce full-sky maps from the Planck timelines for specific periods of time allowing for short-term variability studies of compact sources (e.g., flares). The unique frequency coverage of Planck make these catalogues very valuable for other experiments using the Planck compact source catalogues. For example, experiments like QUIJOTE use Planck selected sources to study the impact of polarized radio source emission on their cosmological fields and other CMB experiments will use Planck polarized compact source information for calibration.
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37

Aghanim, N., M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, et al. "Planck intermediate results." Astronomy & Astrophysics 599 (February 28, 2017): A51. http://dx.doi.org/10.1051/0004-6361/201629164.

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The characterization of the Galactic foregrounds has been shown to be the main obstacle in thechallenging quest to detect primordial B-modes in the polarized microwave sky. We make use of the Planck-HFI 2015 data release at high frequencies to place new constraints on the properties of the polarized thermal dust emission at high Galactic latitudes. Here, we specifically study the spatial variability of the dust polarized spectral energy distribution (SED), and its potential impact on the determination of the tensor-to-scalar ratio, r. We use the correlation ratio of the CBBℓ angular power spectra between the 217 and 353 GHz channels as a tracer of these potential variations, computed on different high Galactic latitude regions, ranging from 80% to 20% of the sky. The new insight from Planck data is a departure of the correlation ratio from unity that cannot be attributed to a spurious decorrelation due to the cosmic microwave background, instrumental noise, or instrumental systematics. The effect is marginally detected on each region, but the statistical combination of all the regions gives more than 99% confidence for this variation in polarized dust properties. In addition, we show that the decorrelation increases when there is a decrease in the mean column density of the region of the sky being considered, and we propose a simple power-law empirical model for this dependence, which matches what is seen in the Planck data. We explore the effect that this measured decorrelation has on simulations of the BICEP2-Keck Array/Planck analysis and show that the 2015 constraints from these data still allow a decorrelation between the dust at 150 and 353 GHz that is compatible with our measured value. Finally, using simplified models, we show that either spatial variation of the dust SED or of the dust polarization angle are able to produce decorrelations between 217 and 353 GHz data similar to the values we observe in the data.
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38

Salvati, L., A. Saro, S. Bocquet, M. Costanzi, B. Ansarinejad, B. A. Benson, L. E. Bleem, et al. "Combining Planck and SPT Cluster Catalogs: Cosmological Analysis and Impact on the Planck Scaling Relation Calibration." Astrophysical Journal 934, no. 2 (August 1, 2022): 129. http://dx.doi.org/10.3847/1538-4357/ac7ab4.

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Abstract We provide the first combined cosmological analysis of the South Pole Telescope (SPT) and Planck cluster catalogs. The aim is to provide an independent calibration for Planck scaling relations, exploiting the cosmological constraining power of the SPT-SZ cluster catalog and its dedicated weak lensing (WL) and X-ray follow-up observations. We build a new version of the Planck cluster likelihood. In the νΛ CDM scenario, focusing on the mass slope and mass bias of Planck scaling relations, we find α SZ = 1.49 − 0.10 + 0.07 and 1 − b SZ = 0.69 − 0.14 + 0.07 , respectively. The results for the mass slope show a ∼4 σ departure from the self-similar evolution, α SZ ∼ 1.8. This shift is mainly driven by the matter density value preferred by SPT data, Ω m = 0.30 ± 0.03, lower than the one obtained by Planck data alone, Ω m = 0.37 − 0.06 + 0.02 . The mass bias constraints are consistent both with outcomes of hydrodynamical simulations and external WL calibrations, (1 − b) ∼ 0.8, and with results required by the Planck cosmic microwave background cosmology, (1 − b) ∼ 0.6. From this analysis, we obtain a new catalog of Planck cluster masses M 500. We estimate the ratio between the published Planck M SZ masses and our derived masses M 500, as a “measured mass bias,” 1 − b M . We analyze the mass, redshift, and detection noise dependence of 1 − b M , finding an increasing trend toward high redshift and low mass. These results mimic the effect of departure from self-similarity in cluster evolution, showing different dependencies for the low-mass, high-mass, low-z, and high-z regimes.
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39

Ghosh, T., F. Boulanger, P. G. Martin, A. Bracco, F. Vansyngel, J. Aumont, J. J. Bock, et al. "Modelling and simulation of large-scale polarized dust emission over the southern Galactic cap using the GASS Hi data." Astronomy & Astrophysics 601 (May 2017): A71. http://dx.doi.org/10.1051/0004-6361/201629829.

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The Planck survey has quantified polarized Galactic foregrounds and established that they are a main limiting factor in the quest for the cosmic microwave background B-mode signal induced by primordial gravitational waves during cosmic inflation. Accurate separation of the Galactic foregrounds therefore binds this quest to our understanding of the magnetized interstellar medium. The two most relevant empirical results from analysis of Planck data are line of sight depolarization arising from fluctuations of the Galactic magnetic field orientation and alignment of filamentary dust structures with the magnetic field at high Galactic latitude. Furthermore, Planck and H I emission data in combination indicate that most of the filamentary dust structures are in the cold neutral medium. The goal of this paper is to test whether these salient observational results, taken together, can account fully for the statistical properties of the dust polarization over a selected low column density region comprising 34% of the southern Galactic cap (b ≤ −30°). To do this, we construct a dust model that incorporates H I column density maps as tracers of the dust intensity structures and a phenomenological description of the Galactic magnetic field. By adjusting the parameters of the dust model, we were able to reproduce the Planck dust observations at 353GHz in the selected region. Realistic simulations of the polarized dust emission enabled by such a dust model are useful for testing the accuracy of component separation methods, studying non-Gaussianity, and constraining the amount of decorrelation with frequency.
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40

Capistrano, Abraão J. S., Luís A. Cabral, Carlos H. Coimbra-Araújo, and José A. P. F. Marão. "On Low Hubble Expansion Rate from Planck Data Anomalies." Galaxies 10, no. 6 (December 19, 2022): 118. http://dx.doi.org/10.3390/galaxies10060118.

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From the linear perturbations of Nash–Greene fluctuations of a background metric, we obtain profiles of Hubble function evolution H(z) and fσ8(z) measurements as compared with the ΛCDM results at intermediate redshifts 0.1<z<1. For parameter estimation, we use joint data from Planck Cosmic Microwave Background (CMB) likelihoods of CMB temperature and polarization angular power spectra, Barionic Acoustic Oscillations (BAO) and local measurements of Hubble constant H0 from the Hubble Space Telescope (HST). We analyze the stability of the effective Newtonian constant Geff and its agreement with Big Bang Nucleosynthesis (BBN) constraints. We show that our results are highly compatible with the ΛCDM paradigm, rather extending the perspective for further studies on redshift-space galaxy clustering data. Moreover, we obtain the CMB TT angular spectra with the Integrated Sachs–Wolfe (ISW) effect, which is weakened on low-l scales. The resulting linear matter power spectrum P(k) profile is also compatible with ΛCDM results but somewhat degenerate with an early dark energy (DE) contribution. Finally, posing a dilemma to the solution of Hubble tension, our results indicate a low Hubble expansion rate suggesting possible anomalies in Planck data in consonance with the recent South Pole Telescope (SPT-3G) data.
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41

Aghanim, N., Y. Akrami, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, et al. "Planck intermediate results." Astronomy & Astrophysics 607 (November 2017): A95. http://dx.doi.org/10.1051/0004-6361/201629504.

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Анотація:
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 ωb, the matter density ωm, the angular size of the sound horizon θ∗, the spectral index of the primordial power spectrum, ns, and Ase− 2τ (where As 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 < 2500Planck temperature power spectrum), each with a prior on τ of 0.07 ± 0.02. We find that the shifts, in units of the 1σ expected dispersion for each parameter, are { Δτ,ΔAse− 2τ,Δns,Δωm,Δωb,Δθ∗ } = { −1.7,−2.2,1.2,−2.0,1.1,0.9 }, with a χ2 value of 8.0. We find that this χ2 value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2σ 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 Ase− 2τ, affects the ℓ> 800 temperature power spectrum solely through the associated change in As 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 2σ 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 ns up and impacts parameters correlated with ns, such as ωm and H0. 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 PlanckTT 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.
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42

Levrier, F., and J. Neveu. "Polarized thermal dust emission as seen by Planck : A comparison with MHD simulations and lessons from a toy model." Proceedings of the International Astronomical Union 11, A29B (August 2015): 745. http://dx.doi.org/10.1017/s1743921316006682.

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AbstractThe Planck satellite (Planck 2015 Results I) has mapped the polarized microwave sky (from 30 GHz to 353 GHz) with unprecedented sensitivity and angular resolution. This wealth of data yields the first complete map of polarized thermal emission from dust in our own Galaxy (Planck Intermediate Results XIX),, shedding new light on the formation of dense cold structures within which new stars and planetary systems are born, under the combined effects of gravity, turbulence and magnetic fields. We present a statistical analysis of this polarized emission from nearby molecular clouds, with an emphasis on the evolution of the maximum polarization fraction observed as a function of column density, and on the anti-correlation between the polarization fraction and the local dispersion of polarization angles. To interpret this data, numerical simulations of anisotropic MHD turbulence (Fromang, Hennebelle, & Teyssier 2006, Hennebelle et al. 2008) underline the essential role played by the topology of the interstellar magnetic field, in particular its large-scale component (Planck Intermediate Results XX). Indeed, the polarization of dust thermal emission at the scales observed by Planck is essentially related to the geometry of the magnetic field. Polarization fractions anti-correlate with column densities, which may be due to a succession of variously polarized structures on the line of sight. They also anti-correlate with the local dispersion of polarization angles. These features are well reproduced by MHD simulations of the diffuse ISM, with comparable correlation coefficients. As an extension to this work published in Planck Intermediate Results XX, the statistical properties of the random component of the interstellar magnetic field are explored using a toy model of the turbulent magnetized ISM based on fractional Brownian motion (fBm) fields. A least-squares analysis to retrieve the statistical properties of the interstellar magnetic field from Planck observations is pursued. Application of this method on the toy model shows good promise, and we are currently working towards its application on Planck data.
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43

Aghanim, N., Y. Akrami, M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, et al. "Planck 2018 results." Astronomy & Astrophysics 641 (September 2020): A5. http://dx.doi.org/10.1051/0004-6361/201936386.

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Анотація:
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 θMC, ωc, ωb, and H0 by more than 30%, and ns 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.
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44

Rubino-Martín, José Alberto. "Planck 2013 Cosmology Results: a Review." Acta Polytechnica CTU Proceedings 1, no. 1 (December 4, 2014): 49–55. http://dx.doi.org/10.14311/app.2014.01.0049.

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Анотація:
This talk presents an overview of the cosmological results derived from the first 15.5 months of observations of the ESA’s <em>Planck</em> mission. These cosmological results are mainly based on the <em>Planck </em>measurements of the cosmic microwave background (CMB) temperature and lensing-potential power spectra, although we also briefly discuss other aspects of the <em>Planck</em> data, as the statistical characterization of the reconstructed CMB maps, or the constraints on cosmological parameters using the number counts of galaxy clusters detected by means of the Sunyaev-Zeldovich effect in the <em>Planck</em> maps. All these results are described in detail in a series of papers released by ESA and the <em>Planck</em> collaboration in March 2013.
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45

Winterberg, F. "Planck Mass Rotons as Cold Dark Matter and Quintessence." Zeitschrift für Naturforschung A 57, no. 3-4 (April 1, 2002): 202–4. http://dx.doi.org/10.1515/zna-2002-3-414.

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Анотація:
According to the Planck aether hypothesis, the vacuum of space is a superfluid made up of Planck mass particles, with the particles of the standard model explained as quasiparticle - excitations of this superfluid. Astrophysical data suggests that ≈70% of the vacuum energy, called quintessence, is a negative pressure medium, with ≈26% cold dark matter and the remaining ≈4% baryonic matter and radiation. This division in parts is about the same as for rotons in superfluid helium, in terms of the Debye energy with a ≈70% energy gap and ≈25% kinetic energy. Having the structure of small vortices, the rotons act like a caviton fluid with a negative pressure. Replacing the Debye energy with the Planck energy, it is conjectured that cold dark matter and quintessence are Planck mass rotons with an energy below the Planck energy.
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46

Natale, U., L. Pagano, M. Lattanzi, M. Migliaccio, L. P. Colombo, A. Gruppuso, P. Natoli, and G. Polenta. "A novel CMB polarization likelihood package for large angular scales built from combined WMAP and Planck LFI legacy maps." Astronomy & Astrophysics 644 (November 26, 2020): A32. http://dx.doi.org/10.1051/0004-6361/202038508.

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We present a cosmic microwave background (CMB) large-scale polarization dataset obtained by combining Wilkinson Microwave Anisotropy Probe (WMAP) in the K, Q, and V bands with the Planck 70 GHz maps. We employed the legacy frequency maps released by the WMAP and Planck collaborations and performed our own Galactic foreground mitigation technique, relying on Planck 353 GHz for polarized dust and on Planck 30 GHz and WMAP K for polarized synchrotron. We derived a single, optimally noise-weighted, low residual foreground map and the accompanying noise covariance matrix. These are shown through χ2 analysis to be robust over an ample collection of Galactic masks. We used this dataset, along with the Planck legacy Commander temperature solution, to build a pixel-based low-resolution CMB likelihood package, whose robustness we tested extensively with the aid of simulations, finding an excellent level of consistency. Using this likelihood package alone, we are able to constrain the optical depth to reionization, τ = 0.069−0.012+0.011 at 68% confidence level, on 54% of the sky. Adding the Planck high-ℓ temperature and polarization legacy likelihood, the Planck lensing likelihood, and BAO observations, we find τ = 0.0714−0.0096+0.0087 in a full ΛCDM exploration. The latter bounds are slightly less constraining than those obtained by employing the Planck High Frequency Instrument’s (HFI) CMB data for large-angle polarization, which only include EE correlations. Our bounds are based on a largely independent dataset that includes TE correlations. They are generally compatible with Planck HFI, but lean towards slightly higher values for τ. We have made the low-resolution Planck and WMAP joint dataset publicly available, along with the accompanying likelihood code.
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47

Akrami, Y., M. Ashdown, J. Aumont, C. Baccigalupi, M. Ballardini, A. J. Banday, R. B. Barreiro, et al. "Planck 2018 results." Astronomy & Astrophysics 641 (September 2020): A11. http://dx.doi.org/10.1051/0004-6361/201832618.

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Анотація:
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 αEE = −2.42 ± 0.02 and αBB = −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 βdP = 1.53±0.02. The difference between indices for polarization and total intensity is βdP−βdI = 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.
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48

Perrott, Yvette C., Kamran Javid, Pedro Carvalho, Patrick J. Elwood, Michael P. Hobson, Anthony N. Lasenby, Malak Olamaie, and Richard D. E. Saunders. "Sunyaev–Zel’dovich profile fitting with joint AMI-Planck analysis." Monthly Notices of the Royal Astronomical Society 486, no. 2 (March 27, 2019): 2116–28. http://dx.doi.org/10.1093/mnras/stz826.

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ABSTRACT We develop a Bayesian method of analysing Sunyaev–Zel’dovich measurements of galaxy clusters obtained from the Arcminute Microkelvin Imager (AMI) radio interferometer system and from the Planck satellite, using a joint likelihood function for the data from both instruments. Our method is applicable to any combination of Planck data with interferometric data from one or more arrays. We apply the analysis to simulated clusters and find that when the cluster pressure profile is known a priori, the joint data set provides precise and accurate constraints on the cluster parameters, removing the need for external information to reduce the parameter degeneracy. When the pressure profile deviates from that assumed for the fit, the constraints become biased. Allowing the pressure profile shape parameters to vary in the analysis allows an unbiased recovery of the integrated cluster signal and produces constraints on some shape parameters, depending on the angular size of the cluster. When applied to real data from Planck-detected cluster PSZ2 G063.80+11.42, our method resolves the discrepancy between the AMI and Planck Y-estimates and usefully constrains the gas pressure profile shape parameters at intermediate and large radii.
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49

MANDOLESI, NAZZARENO, CARLO BURIGANA, ALESSANDRO GRUPPUSO, and PAOLO NATOLI. "THE PLANCK MISSION: RECENT RESULTS, COSMOLOGICAL AND FUNDAMENTAL PHYSICS PERSPECTIVES." International Journal of Modern Physics D 22, no. 14 (December 2013): 1330029. http://dx.doi.org/10.1142/s0218271813300292.

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We provide a description of the latest status and performance of the Planck satellite, focusing on the final predicted sensitivity of Planck. The optimization of the observational strategy for the additional surveys following the nominal 15 months of integration (about two surveys) originally allocated and the limitation represented by astrophysical foreground emissions are presented. An outline of early and intermediate astrophysical results from the Planck Collaboration is provided. A concise view of some fundamental cosmological results that will be achieved by exploiting Planck's full set of temperature and polarization data are presented. Finally, the perspectives opened by Planck in answering some key questions in fundamental physics, with particular attention to parity symmetry analyses, are described.
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50

Tauber, Jan A. "FM5. The Legacy of Planck." Proceedings of the International Astronomical Union 11, A29B (August 2015): 39–48. http://dx.doi.org/10.1017/s1743921316004518.

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AbstractThis paper is an introduction to Focus Meeting 5 held at the IAU's General Assembly held in Honolulu in August 2015. It describes the rationale for the meeting, and summarizes the introductory talk to FM5, which contained a description of the Planck data products released by ESA and the Planck Collaboration in the first half of 2015.
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