Day 1440

Wednesday.

1807.06205
Planck 2018 results. I. Overview and the cosmological legacy of Planck
Planck Collaboration, et al

ESA's Planck satellite, which was dedicated to studying the early Universe and its subsequent evolution, was launched on 14 Man 2009.  It scanned the microwave and submillimetre sky continuously between 12 Aug. 2009 and 23 Oct 2013, producing deep, high-resolution, all-sky maps in 9 frequency bands from 30 to 857 GHz.  This paper presents the cosmological legacy of Planck, which currently provides the strongest constraints on the parameters of the standard cosmological model and some f the tightest limits available on deviations from that model.  The 6 parameter LCDM model continues to provide an excellent fit to the CMB data at high and low z, describing the cosmo information in over a billion map pixels with just 6 parameters.  With 18 peaks in the T and polarization angular power spectra constrained well, Planck m causers 5 of the 6 parameters to better than 1% (simultaneously), with the best-determined parameter (theta-*) now known to 0.03%.  Describe the multi-component sky as seed by Planck, the success of the LCDM model, and the connection to lower-redshift probes of structure formation.  Also give a comprehensive summary of the major changes introduced in the 2018 release.  The Planck data, alone and in combination with other probes, provide stringent constraints on the models of the early Universe and the LSS within which all astrophysical objects form and evolve.  Discuss some lessons learned from the Planck mission, and highlight areas ripe for further experimental advances.


1807.06209
Planck 2018 results. VI.  Cosmological parameters
Planck Collaboration, et al

Present cosmo parameter realists from the final full-mission Planck measurement of the CMB anisotropies.  Find good consistency with the standard spatially-flat 6-parameter LCDM cosmology having a power-law spectrum of adiabatic scalar perturbations (denoted "base LCDM" in this paper), from polarization, temperature, and lensing, separately and in combination.  A combined analysis gives DM density Omega_c h^2 = 0.120 ± 0.001, baryon density Omega_b h^2 = 0.0224±0.0001, scale spectral index n_s=0.965 ± 0.004, and optical depth tau=0.054±0.007 (in this abstract quote 68% CL on measured parameters and 95% on upper limits).  The angular acoustic scale is measured to 0.03% precision, with 100 theta_*=1.0411±0.0003.  These results are only weakly dependent on the cosmological model and remain stable, with somewhat increased errors, in many commonly considered extensions.  Assuming the base LCDM cosmology, the inferred late-universe parameters are: H_0=(67.4±0.5) km/s/Mpc; Omega_m=0.315±0.007; and sigma_8=0.811±0.006.  Find no compelling evidence for extensions to the base LCDM model.  Combining with BAO, constrain the effective extra relativistic degrees of freedom to be N_eff = 2.99±0.17, and the neutrino mass is tightly constrained to sum m_nu<0.12 eV.  The CMB spectra continue to prefer higher lensing amplitudes than predicted in based LCDM at over 2 sigma, which pulls some parameters that affect the lensing amplitude away from the base LCDM model; however, this is not supported by the lensing reconstruction or (in models that also change the background geometry) BAO data.