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Studies of cosmic microwave background (CMB) are often limited by foreground contamination. Foreground cleaning is performed in either harmonic or pixel space after data cuts have excluded sky areas of strong contamination. We present a nearly full-sky CMB temperature map with only 1% of pixels masked. To derive this map, we make use of six full-sky template maps at foreground-dominated frequencies from different experiments smoothed to 1° and rely on the combination of these weighted maps to trace the morphology of foreground contamination. We do not impose any spectral index constraints but only fit for template amplitudes at each target frequency. We clean Wilkinson Microwave Anisotropy Probe and Planck maps at a set of target frequencies and conduct quality tests at the level of the maps, pixel histograms, and power spectra to select four CMB maps that are cleaned with negligible foreground contamination and only 1% masked pixels and no inpainting. We recommend use of these cleaned CMB maps for low-multipole (ℓ < 30) studies.

We present a cosmic microwave background (CMB) temperature power spectrum measurement at large angular scales from WMAP and Planck maps that were cleaned of foregrounds using a template-based approach described in the first paper of this series. We recover essentially the full-sky CMB information at multipoles ℓ < 30 with only 1% of pixels near the Galactic plane masked and with no inpainting. Notable features continue to appear: (a) a low quadrupole power compared to the best-fit Planck 2018 ΛCDM spectrum at 2.2σ, (b) a dip in the range 20 ≤ ℓ ≤ 27, and (c) an overall ℓ < 30 power level low of the ΛCDM prediction derived from higher multipole moments. Given the different methodology from previous analyses and the nearly full-sky solution presented here, these features do not plausibly arise from foreground contamination, systematic errors, masking, or mode mixing. Our overall ℓ < 30 amplitude constraint is consistent with published WMAP (77% sky fraction) and Planck (86%) results at 1.2σ and 0.6σ, respectively, accounting for the improvement in statistical precision. We present a new ℓ < 30 likelihood for use with the Cobaya package. Parameter constraints from joint fits with the higher-multipole Planck data are consistent with the published Planck results; for example, we find H0 = 67.35 ± 0.54 km s−1 Mpc−1 in a joint ΛCDM fit.

Unexpected features have been observed in the cosmic microwave background (CMB) temperature on large scales. We revisit these CMB anomalies using new foreground-cleaned CMB temperature maps derived in a companion paper from WMAP and Planck data, which are tailored to low-resolution analysis and require only minimal masking of 1% of the sky. These maps allow us to assess the impact of foreground-cleaning methods and the choice of sky cut on the significance of five commonly studied CMB anomalies. We find a notable impact of the choice of galactic mask on the significance of two anomalies: the significance of the low real-space correlation function and of the local-variance asymmetry reduces from ∼3σ for the Planck common mask with 26% masked fraction to ∼2σ for the 1% mask. We find good agreement between the two sky cuts for the low northern variance, ∼3σ, and the parity asymmetry, ∼2σ. For the quadrupole-octopole alignment, we find good agreement between the 1% mask result and the full-sky results in the literature, ∼3σ. Thus, using a larger fraction of the sky enabled by improved foreground cleaning reduces the significance of two commonly studied CMB anomalies. Overall, for an alternative physical model to be convincingly favored over Λ cold dark matter (CDM) with statistically isotropic Gaussian fluctuations, it would need to explain multiple CMB anomalies, or better describe some other type of measurement in addition to a CMB anomaly.

Quantum fluctuations of the gravitational field in the early Universe, amplified by inflation, produce a primordial gravitational-wave background across a broad frequency band. We derive constraints on the spectrum of this gravitational radiation, and hence on theories of the early Universe, by combining experiments that cover 29 orders of magnitude in frequency. These include Planck observations of cosmic microwave background temperature and polarization power spectra and lensing, together with baryon acoustic oscillations and big bang nucleosynthesis measurements, as well as new pulsar timing array and ground-based interferometer limits. While individual experiments constrain the gravitational-wave energy density in specific frequency bands, the combination of experiments allows us to constrain cosmological parameters, including the inflationary spectral index nt and the tensor-to-scalar ratio r . Results from individual experiments include the most stringent nanohertz limit of the primordial background to date from the Parkes Pulsar Timing Array, ΩGW(f)<2.3×10−10 . Observations of the cosmic microwave background alone limit the gravitational-wave spectral index at 95% confidence to nt≲5 for a tensor-to-scalar ratio of r=0.11 . However, the combination of all the above experiments limits nt<0.36 . Future Advanced LIGO observations are expected to further constrain nt<0.34 by 2020. When cosmic microwave background experiments detect a nonzero r , our results will imply even more stringent constraints on nt and, hence, theories of the early Universe.

We construct a three-dimensional and redshift-evolutionary X-ray and ultraviolet (L X –L UV ) luminosity relation for quasars from the powerful statistic tool called copula, and find that the constructed L X –L UV relation from copula is more viable than the standard one and the observations favor the redshift-evolutionary relation more than 3σ. The Akaike and Bayes information criterions indicate that the quasar data support strongly the three-dimensional L X –L UV relation. Our results show that the quasars can be regarded as a reliable indicator of the cosmic distance if the L X –L UV relation from copula is used to calibrate quasar data.

We report the discovery of two metastable neutral helium (He I*) absorbers in the Milky Way, and use the upgraded CRyogenic InfraRed Echelle Spectrograph (or CRIRES) on the Very Large Telescope to determine the helium isotope ratio, 3He/4He, along these sight lines. We have also obtained deeper observations of a third sight line to report a ≲4% precision measure of 3He/4He in the Orion Nebula. These data have allowed us to place a 2σ limit on the time variability of He I* absorption in the Orion Nebula, dlog10[N(HeI∗)/cm−2]/dt≤7.2×10−4dexyr−1 (<0.17% yr−1), suggesting that these absorbers are in radiative equilibrium. We compute new galactic chemical evolution models of the Milky Way, and use our observations to infer the primordial helium isotope ratio and a scaling factor for the yields reported by nucleosynthesis calculations. Based on the data and models that we report here, we infer a best-fit value (3He/4He) P=(1.15−0.21+0.24)×10−4 , which agrees with Big Bang nucleosynthesis calculations that assume the Standard Model of particle physics in combination with the baryon density inferred from cosmic microwave background temperature fluctuations. We infer the stellar yield scale relative to the solar metallicity, y/Z⊙=2.12−0.29+0.31 , which is somewhat higher than previously found. Finally, we note that the forthcoming generation of extremely large telescopes is poised to determine 3He/4He in more metal-poor environments, enabling a model-independent determination of the primordial value.

We investigate how the dark energy properties impact the constraints on the total neutrino mass in interacting dark energy (IDE) models. In this study, we focus on two typical interacting dynamical dark energy models, i.e., the interacting w cold dark matter (I w CDM) model and the interacting holographic dark energy (IHDE) model. To avoid the large-scale instability problem in IDE models, we apply the parameterized post-Friedmann approach to calculate the perturbation of dark energy. We employ the Planck 2015 cosmic microwave background temperature and polarization data, combined with low-redshift measurements on baryon acoustic oscillation distance scales, type Ia supernovae, and the Hubble constant, to constrain the cosmological parameters. We find that the dark energy properties could influence the constraint limits on the total neutrino mass. Once dynamical dark energy is considered in the IDE models, the upper bounds of ∑ m v will be changed. By considering the values of χ 2 min , we find that in these IDE models the normal hierarchy case is slightly preferred over the inverted hierarchy case; for example, Δ χ 2 = 2.720 is given in the IHDE+∑ m v model. In addition, we also find that in the I w CDM+∑ m v model β = 0 is consistent with current observational data inside the 1 σ range, and in the IHDE+∑ m v model β > 0 is favored at more than 2 σ level.

A bstract Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a fully stable NEC violation can be realized in the “beyond Horndeski” theory, it remains an open question whether a violation of the NEC is allowed by some fundamental properties of UV-complete theories or the consistency requirements of effective field theory (EFT). We investigate the tree-level perturbative unitarity for stable NEC violations in the contexts of both Galileon and “beyond Horndeski” genesis cosmology, in which the universe is asymptotically Minkowskian in the past. We find that the constraints of perturbative unitarity imply that we may need some unknown new physics below the cut-off scale of the EFT other than that represented by the “beyond Horndeski” operators.

The Cold Dark Matter (CDM) hypothesis accurately predicts large-scale structure formation and fits the Cosmic Microwave Background temperature fluctuations (CMB). However, observations of the inner regions of dark matter halos and dwarf galaxy satellites have consistently posed challenges to CDM. On the other hand, the Modified Newtonian Dynamics (MOND) hypothesis can explain galactic phenomena but fails to account for the complex shape of the CMB and matter power spectra. CDM and MOND are effective in nearly mutually exclusive regimes, prompting the question: is there a physical mechanism where CDM and MOND share a common origin? Q-balls, which are localized, non-topological solitons, can be a bridge between the two hypotheses. Q-balls formed in the early Universe can mimic CDM at cosmological scales. Interestingly, Q-balls can exhibit MOND-like behavior in the late Universe at galactic scales, providing a unified framework. Specifically, we demonstrate that millicharged composite Q-balls formed from complex scalar fields, decoupled from the background radiation, can naturally arise during the radiation-dominated epoch. From the matter-radiation equality, we also obtain the mass of Q-balls to be 1 eV, which are much smaller than the electron mass. Using the constraints from the invisible decay mode of ortho-positronium, we obtain Q < 3.4 × 10 - 5 . We also establish an upper bound on the number density of Q-balls, which depends on the charge of the Q-ball and the small initial charge asymmetry. Furthermore, we demonstrate that the MOND naturally emerges at the galactic scale within the framework of our Q-ball model.

We present a new, model-independent measurement of the clustering amplitude of galaxies and the growth of cosmic large-scale structures from the Baryon Oscillation Spectroscopic Survey (BOSS) 12th data release. This is achieved by generalizing harmonic-space power spectra for galaxy clustering to measure separately the magnitudes of the density and the redshift-space distortion terms, respectively related to the clustering amplitude of structures, b σ 8(z), and their growth, f σ 8(z). We adopt a tomographic approach with 15 redshift bins in z ∈ [0.15, 0.67]. We restrict our analysis to strictly linear scales, implementing a redshift-dependent maximum multipole for each bin. The measurements do not appear to suffer from systematic effects, and they show excellent agreement with the theoretical predictions from the Planck cosmic microwave background analysis assuming a ΛCDM cosmology. Our results also agree with previous analyses by the BOSS collaboration. Furthermore, our method provides the community with a new tool for data analyses of the cosmic large-scale structure, complementary to state-of-the-art approaches in configuration or Fourier space. Among its merits, we list: it being more agnostic with respect to the underlying cosmological model; its roots in a well-defined and gauge-invariant observable; the possibility to account naturally for wide-angle effects and even relativistic corrections on ultra-large scales; and the capability to perform an almost arbitrarily fine redshift binning with little computational effort. These aspects are all the more relevant for the oncoming generation of cosmological experiments such as Euclid, the Dark Energy Spectroscopic Instrument, the Legacy Survey of Space and Time, and the SKA Project.