Cosmic Microwave Background Measurements Research Articles

Spectro-spatial evolution of the CMB. Part III. Transfer functions, power spectra and Fisher forecasts

In this paper, we provide the first computations for the distortion transfer functions of the cosmic microwave background (CMB) in the perturbed Universe, following up on paper I and II in this series. We illustrate the physical effects inherent to the solutions, discussing and demonstrating various limiting cases for the perturbed photon spectrum. We clarify the relationship between distortion transfer functions and the photon spectrum itself, providing the machinery that can then compute constrainable CMB signal power spectra including spectral distortions for single energy injection and decaying particle scenarios. Our results show that the μ × T and y × T power spectra reach levels that can be constrained with current and future CMB experiments without violating existing constraints from COBE/FIRAS. The amplitude of the cross-correlation signal directly depends on the average distortion level, therefore establishing a novel fundamental link between the state of the primordial plasma from redshift 103 ≲ z ≲ 3 × 106 and the frequency-dependent CMB sky. This providesa new method to constrain average early energy release using CMB imagers. As an example we derive constraints on single energy release and decaying particle scenarios. This shows that LiteBIRD may be able to improve the energy release limits of COBE/FIRAS by up to a factor of ≃ 2.5, while PICO could tighten the constraints by more than one order of magnitude. The signals considered here could furthermore provide a significant challenge to reaching cosmic variance-limited constraints on primordial non-Gaussianity from distortion anisotropy studies. Our work further highlights the immense potential for a synergistic spectroscopic approach to future CMB measurements and analyses.

Constraints on cosmological model in Weyl-Cartan spacetime from astronomical measurements

In order to give some lights on the issue of Hubble tension, alternative to Riemannian spacetime, we investigate a cosmological model in Weyl-Cartan spacetime by astronomical measurements, where a new density parameter Ω ϕ is introduced to denote the non-Riemannian spacetime structure, which scales as ∼(1 + z)6. Based on Markov Chain Monte Carlo estimation and taking astronomical measurements of cosmic microwave background (Planck 2018), baryon acoustic oscillations and Type Ia supernova (Pantheon), model parameters of our considering case are constrained. Our results show that Hubble tension cannot be alleviated in Weyl-Cartan cosmology. However, constraints on the parameter Ω ϕ can not be distinguished from ΛCDM model in 1σ confidence region. Moreover, the space of the Universe is infinite and unbounded, and an upper limit of the model parameter Ω ϕ is also obtained. Additionally, it is worth noting that results obtained in this work are valid for models that the scaling behavior of density parameters is same to our considering case.

Decaying Dark Matter and Lyman-α forest constraints

Decaying Cold Dark Matter (DCDM) is a model that is currently under investigation regarding primarily the S 8 tension between cosmic microwave background (CMB) and certain large-scale structure measurements. The decay into one massive and one (or more) massless daughter particle(s) leads to a suppression of the power spectrum in the late universe that depends on the relative mass splitting ϵ = (1 - m 2/M 2)/2 between the mother and massive daughter particle as well as the lifetime τ. In this work we investigate the impact of the BOSS DR14 one-dimensional Lyman-α forest flux power spectrum on the DCDM model using a conservative effective model approach to account for astrophysical uncertainties. Since the suppression of the power spectrum due to decay builds up at low redshift, we find that regions in parameter space that address the S 8 tension can be well compatible with the Lyman-α forest. Nevertheless, for values of the degeneracy parameter ϵ ∼ 0.1-0.5%, for which the power suppression occurs within the scales probed by BOSS Lyman-α data, we find improved constraints compared to previous CMB and galaxy clustering analyses, obtaining τ ≳ 18 Gyrs for small mass splitting. Furthermore, our analysis of the BOSS Lyman-α flux power spectrum allows for values τ ∼ 102 Gyrs, ϵ ∼ 1%, that have been found to be preferred by a combination of Planck and galaxy clustering data with a KiDS prior on S 8, and we even find a hint for a marginal preference within this regime.

Dark matter search with CMB: a study of foregrounds

The energy injected from dark matter annihilation and decay processes potentially raises the ionisation of the intergalactic medium and leaves visible footprints on the anisotropy maps of the cosmic microwave background (CMB). Galactic foregrounds emission in the microwave bands contaminate the CMB measurement and may affect the search for dark matter's signature. In this paper, we construct a full CMB data and foreground simulation based on the design of the next-generation ground-based CMB experiments. The foreground residual after the components separation on maps is fully considered in our data analysis, accounting for various contamination from the emission of synchrotron, thermal dust, free-free and spinning dust. We analyse the corresponding sensitivity on dark matter parameters from the temperature and polarization maps, and we find that the CMB foregrounds leave a non-zero yet controllable impact on the sensitivity. Comparing with statistics-only analysis, the CMB foreground residual leads to a factor of at most 19% weakening on energy-injection constraints, depending on the specific dark matter process and experimental configuration. Strong limits on dark matter annihilation rate and decay lifetime can be expected after foreground subtraction.

Inflationary potential as seen from different angles: model compatibility from multiple CMB missions

The cosmic microwave background (CMB) temperature and polarization anisotropies, as observed by independent astronomical missions such as WMAP, Planck, and most recently the Atacama Cosmology Telescope and the South Pole Telescope have played a vital role in accurately constraining cosmological theories and models, establishing cosmic inflation as the most widely accepted theory for describing the physics of the early Universe. However, the absence of a definitive detection of B-mode polarization and the emerging discrepancies among different CMB experiments present a challenge in determining which inflationary models best explain the observed data. In this work, we further explore this difficulty and conduct a case study by analyzing four well-known inflationary potentials in light of the latest CMB temperature and polarization anisotropy measurements and lensing data released by the Planck satellite and the Atacama Cosmology Telescope. Additionally, we incorporate B-modes polarization data from the BICEP/Keck Collaboration, as well as Baryon Acoustic Oscillations and Redshift Space Distortions measurements from BOSS DR12 and eBOSS DR16. We show that the most typical models such as Starobinsky and α-attractors are in disagreement with the Atacama Cosmology Telescope small-scale CMB measurements, particularly when combined with B-modes polarization data. On the other hand, these potentials are in perfect agreement with the Planck measurements at larger angular scales. This dichotomy makes it challenging to identify a single model or a group of models that can be universally considered as the preferred choice based on all available CMB observations.

Extended analysis of neutrino-dark matter interactions with small-scale CMB experiments

We explore an extension of the standard ΛCDM model by including an interaction between neutrinos and dark matter, and making use of the ground based telescope data of the Cosmic Microwave Background (CMB) from the Atacama Cosmology Telescope (ACT). An indication for a non-zero coupling between dark matter and neutrinos (both assuming a temperature independent and T2 dependent cross-section) is obtained at the 1σ level coming from the ACT CMB data alone and when combined with the Planck CMB and Baryon Acoustic Oscillations (BAO) measurements. This result is confirmed by both fixing the effective number of relativistic degrees of freedom in the early Universe to the Standard Model value of Neff=3.044, and allowing Neff to be a free cosmological parameter. Furthermore, when performing a Bayesian model comparison, the interacting νDM (+Neff) scenario is mostly preferred over a baseline ΛCDM (+Neff) cosmology. The preferred value is then used as a benchmark and the potential implications of dark matter’s interaction with a sterile neutrino are discussed.

Cosmic birefringence from neutrino and dark matter asymmetries

In light of the recent measurement of the nonzero Cosmic Microwave Background (CMB) polarization rotation angle from the Planck 2018 data, we explore the possibility that such a cosmic birefringence effect is induced by coupling a fermionic current with photons via a Chern-Simons-like term. We begin our discussion by rederiving the general formulae of the cosmic birefringence angle with correcting a mistake in the previous study.We then identify the fermions in the current as the left-handed electron neutrinos and asymmetric dark matter (ADM) particles, since the rotation angle is sourced by the number density difference between particles and antiparticles. For the electron neutrino case, with the value of the degeneracy parameter ξν e recently measured by the EMPRESS survey, we find a large parameter space which can explain the CMB photon polarization rotations. On the other hand, for the ADM solution, we consider two benchmark cases with Mχ = 5 GeV and 5 keV. The former is the natural value of the ADM mass if the observed ADM and baryon asymmetry in the Universe are produced by the same mechanism, while the latter provides a warm DM candidate. In addition, we explore the experimental constraints from the CMB power spectra and the DM direct detections.

Inevitable manifestation of wiggles in the expansion of the late Universe

Using the fact that the comoving angular diameter distance to the last scattering surface is strictly constrained almost model independently, we show that, for any model agreeing with the standard $\mathrm{\ensuremath{\Lambda}}$CDM model on its background dynamics at $z\ensuremath{\sim}0$ and size of the comoving sound horizon at last scattering, the deviations of the Hubble radius from the one of the standard $\mathrm{\ensuremath{\Lambda}}$CDM model must be a member of the set of admissible wavelets. The family of models characterized by this framework also offers nontrivial oscillatory behaviors in various functions that define the kinematics of the Universe, even when the wavelets themselves are very simple. We also discuss the consequences of attributing these kinematics to, first, dark energy, and second, varying gravitational coupling strength. Utilizing some simplest wavelets, we demonstrate the competence of this framework in describing the baryon acoustic oscillation (BAO) data without any modifications to the agreement with cosmic microwave background measurements. This framework also provides a natural explanation for the bumps found in nonparametric observational reconstructions of the Hubble parameter and dark energy density as compensations of the dips suggested by some BAO data, and questions the physical reality of their existence. We note that utilizing this framework on top of the models that agree with both the cosmic microwave background and local ${H}_{0}$ measurements but are held back by BAO data, one may resurrect these models through the wiggly nature of wavelets that can naturally accommodate the BAO data. Finally, we also suggest narrowing the plausible set of admissible wavelets to further improve our framework by imposing conditions from expected kinematics of a viable cosmological model or first principle fundamental physics such as energy conditions.

Production of Primordial Black Holes in Improved E-Models of Inflation

E-type α-attractor models of single-field inflation were generalized further in order to accommodate production of primordial black holes (PBHs) via adding a near-inflection point to the inflaton scalar potential at smaller scales, in good agreement with measurements of cosmic microwave background (CMB) radiation. A minimal number of new parameters were used but their fine-tuning was maximized in order to increase the possible masses of PBHs formed during an ultra-slow-roll phase, leading to a large enhancement in the power spectrum of scalar (curvature) perturbations by 6 or 7 orders of magnitude against the power spectrum of perturbations observed in CMB. It was found that extreme fine-tuning of the parameters in our models can lead to the formation of moon-sized PBHs, with masses of up to 1026 g, still in agreement with CMB observations. Quantum corrections are known to lead to the perturbative upper bound on the amplitude of large scalar perturbations responsible for PBH production. The quantum (one-loop) corrections in our models were found to be suppressed by one order of magnitude for PBHs with masses of approximately 1019 g, which may form the whole dark matter in the Universe.

Characterization of a half-wave plate for cosmic microwave background circular polarization measurement with POLARBEAR.

A half-wave plate (HWP) is often used as a modulator to suppress systematic error in the measurements of cosmic microwave background (CMB) polarization. A HWP can also be used to measure circular polarization (CP) through its optical leakage from CP to linear polarization. The CP of the CMB is predicted from various sources, such as interactions in the Universe and extension of the standard model. Interaction with supernova remnants of population III stars is one of the brightest CP sources. Thus, the observation of the CP of CMB is a new tool for searching for population III stars. In this paper, we demonstrate the improved measurement of the leakage coefficient using the transmission measurement of an actual HWP in the laboratory. We measured the transmittance of linearly polarized light through the HWP used in Polarbear in the frequency range of 120-160GHz. We evaluate the properties of the HWP by fitting the data with a physical model using the Markov Chain Monte Carlo method. We then estimate the band-averaged CP leakage coefficient using the physical model. We find that the leakage coefficient strongly depends on the spectra of CP sources. We thus calculate the maximum fractional leakage coefficient from CP to linear polarization as 0.133 ± 0.009 in the Rayleigh-Jeans spectrum. The nonzero value shows that Polarbear has a sensitivity to CP. Additionally, because we use the bandpass of detectors installed in the telescope to calculate the band-averaged values, we also consider systematic effects in the experiment.

Testing decaying dark matter models as a solution to the S8 tension with the thermal Sunyaev-Zel’dovich effect

Considering possible solutions to the S8 tension between the Planck cosmic microwave background (CMB) measurement and low-redshift probes, we extended the standard ΛCDM cosmological model by including decay of dark matter (DDM). We first tested the DDM model in which dark matter decays into a form of noninteracting dark radiation. Under this DDM model, we investigated the impacts of DDM on the Sunyaev Zel’dovich (SZ) effect by varying the decay lifetime, Γ−1, including the background evolution in cosmology and the nonlinear prescription in the halo mass function. We performed a cosmological analysis under the assumption of this extended cosmological model by combining the latest high-redshift Planck CMB measurement and low-redshift measurements of the SZ power spectrum as well as the baryonic acoustic oscillations (BAO) and luminosity distances to type Ia supernovae (SNIa). Our result shows a preference for Γ−1 ∼ 220 Gyr with a lower bound on the decay lifetime of ∼38 Gyr at 95% confidence level. Additionally, we tested the other DDM model in which dark matter decays into warm dark matter and dark radiation. This model supports Γ−1 ∼ 137 Gyr to resolve the S8 tension with a lower bound on the decay lifetime of ∼24 Gyr at 95% confidence level. Comparing these two models, we find that the second leads to slightly better reconciliation of the S8 tension.

A framework to mitigate patchy reionization contamination on the primordial gravitational wave signal

ABSTRACT One of the major goals of future cosmic microwave background (CMB) B-mode polarization experiments is the detection of primordial gravitational waves through an unbiased measurement of the tensor-to-scalar ratio r. Robust detection of this signal will require mitigating all possible contamination to the B-mode polarization from astrophysical origins. One such extragalactic contamination arises from the patchiness in the electron density during the reionization epoch. Along with the signature on CMB polarization, the patchy reionization can source secondary anisotropies on the CMB temperature through the kinetic Sunyaev–Zeldovich (kSZ) effect. In order to study the impact of this foreground for the upcoming CMB missions, we present a self-consistent framework to compute the CMB anisotropies based on a physically motivated model of reionization. We show that the value of r can bias towards a higher value if the secondary contribution from reionization is neglected. However, combining small-scale kSZ signal, large-scale E-mode polarization, and B-mode polarization measurements, we can put constraints on the patchiness in electron density during reionization and can mitigate its impact on the value of r. CMB missions such as CMB-S4 and PICO may experience a bias of >0.17σ which can go as high as ∼0.73σ for extreme reionization models allowed by the Planck and SPT CMB measurements. As future experiments target to measure r at 5σ, this is likely to affect the measurement significance and hence possibly affect the claim of detection of r, if not mitigated properly by using joint estimations of different reionization observables.

Fuzzy Dark Matter as a Solution to Reconcile the Stellar Mass Density of High-z Massive Galaxies and Reionization History

The JWST early release data show unexpected high stellar mass densities of massive galaxies at 7 < z < 11. A high star formation efficiency is probably needed to explain this. However, such a high star formation efficiency would greatly increase the number of ionizing photons, which would be in serious conflict with current cosmic microwave background (CMB) and other measurements of cosmic reionization history. To solve this problem, we explore fuzzy dark matter (FDM), which is composed of ultra-light scalar particles, e.g., ultra-light axions, and calculate its halo mass function and stellar mass density for different axion masses. We find that a FDM model with m a ≃ 5 × 10−23 eV and a possible uncertainty range ∼3 × 10−23–10−22 eV can effectively suppress the formation of small halos and galaxies, so that with higher star formation efficiency both the JWST data at z ∼ 8 and the reionization history measurements from optical depth of CMB scattering and ionization fraction can be simultaneously matched. We also find that the JWST data at z ∼ 10 are still too high to fit in this scenario. We note that the estimated mean redshift of the sample may have large uncertainty, that it can be as low as z ∼ 9 depending on adopted spectral energy distribution templates and photometric-redshift code. In addition, warm dark matter with ∼keV mass can also be an alternative choice, since it should have similar effects on halo formation as FDM.

Model-independent determination of H0 and ΩK, 0 using time-delay galaxy lenses and gamma-ray bursts

ABSTRACT Combining the ‘time-delay distance’ (DΔt) measurements from galaxy lenses and other distance indicators provides model-independent determinations of the Hubble constant (H0) and spatial curvature (ΩK, 0), only based on the validity of the Friedmann–Lemaître–Robertson–Walker (FLRW) metric and geometrical optics. To take the full merit of combining DΔt measurements in constraining H0, we use gamma-ray burst (GRB) distances to extend the redshift coverage of lensing systems much higher than that of Type Ia Supernovae (SNe Ia) and even higher than quasars, whilst the general cosmography with a curvature component is implemented for the GRB distance parametrizations. Combining Lensing + GRB yields $H_0=71.5^{+4.4}_{-3.0}$ km s−1 Mpc−1 and $\Omega _{K,0} = -0.07^{+0.13}_{-0.06}$ (1σ). A flat-universe prior gives slightly an improved $H_0 = 70.9^{+4.2}_{-2.9}$ km s−1Mpc−1. When combining Lensing+GRB + SN Ia, the error bar ΔH0 falls by 25 per cent, whereas ΩK, 0 is not improved due to the degeneracy between SN Ia absolute magnitude, MB, and H0 along with the mismatch between the SN Ia and GRB Hubble diagrams at z ≳ 1.4. Future increment of GRB observations can help to moderately eliminate the MB–H0 degeneracy in SN Ia distances and ameliorate the restrictions on cosmographic parameters along with ΩK, 0 when combining Lensing+SN Ia + GRB. We conclude that there is no evidence of significant deviation from a (an) flat (accelerating) universe and H0 is currently determined at 3 per cent precision. The measurements show great potential to arbitrate the H0 tension between the local distance ladder and cosmic microwave background measurements and provide a relevant consistency test of the FLRW metric.

Searching for bounce signature in the early universe from current and future large-scale structure surveys

ABSTRACT The bounce scenario has been an interesting research topic in cosmology, due to its ability to resolve both the singularity problem and the trans-Planckian issue, which are left from the standard inflationary theory. In previous works, we considered an inflationary cosmology with a preceding non-singular bounce and found that this model could suppress the primordial power spectrum at large scales and leave the signature on the angular power spectra of cosmic microwave background (CMB). In this work, we extend this analysis to the large-scale structure (LSS) measurements. Firstly, we consider the angular power spectrum of current LSS data sets, such as the 2MPZ, SDSS-DR12, and DES Y3 galaxy surveys at low redshifts and the NVSS radio survey at high redshifts, and do not obtain good constraint on the model parameters, due to the precision limitation at large scales. When we include the Planck CMB measurements, the constraints become a little bit better: the amplitude Ar = 0.8 ± 0.2 and the slope ${\rm log_{10}}(k_B)=-2.6^{+0.3}_{-1.0}$ at 68 per cent confidence level. In order to evaluate the constraining ability of future LSS surveys, we forecast the clustering measurements, such as the galaxy angular power spectrum and the galaxy lensing shear power spectrum, based on the China Space Station Telescope photometric survey. We find that the standard deviations of model parameters will be significantly shrunk, ΔAr = 0.1 and Δlog10(kB) = 0.1, due to the high precision measurements. Finally, we consider the bounce feature and the primordial non-Gaussianity from inflation theory simultaneously and find that in the bounce inflationary model the limit on fNL will be weaker than that obtained in the standard inflationary model, due to the strong degeneracy among parameters.

Detection and estimation of the cosmic dipole with the einstein telescope and cosmic explorer

ABSTRACTOne of the open issues of the standard cosmological model is the value of the cosmic dipole measured from the Cosmic Microwave Background (CMB), as well as from the number count of quasars and radio sources. These measurements are currently in tension, with the number count dipole being 2–5 times larger than expected from CMB measurements. This discrepancy has been pointed out as a possible indication that the cosmological principle is not valid. In this paper, we explore the possibility of detecting and estimating the cosmic dipole with gravitational waves (GWs) from compact binary mergers detected by the future next-generation detectors Einstein Telescope and Cosmic Explorer. We model the expected signal and show that for binary black holes, the dipole amplitude in the number count of detections is independent of the characteristics of the population and provides a systematic-free tool to estimate the observer velocity. We introduce techniques to detect the cosmic dipole from number counting of GW detections and estimate its significance. We show that a GW dipole consistent with the amplitude of the dipole in radio galaxies would be detectable with &amp;gt;3σ significance with a few years of observation (106 GW detections) and estimated with a 16 per cent precision, while a GW dipole consistent with the CMB one would require at least 107 GW events for a confident detection. We also demonstrate that a total number Ntot of GW detections would be able to detect a dipole with amplitude $v_o/c \simeq 1/\sqrt{N_{\rm tot}}$.

Pole inflation and primordial black holes formation in Starobinsky-like supergravity

We extend the Cecotti–Kallosh model of Starobinsky inflation in supergravity by adding a holomorphic function to the superpotential in order to generate a large peak in the power spectrum of scalar (curvature) perturbations. In our approach, the singular non-canonical kinetic terms are largely responsible for inflation (as an attractor solution), whereas the superpotential is engineered to generate a production of PBH. We study the cases with (a) a linear holomorphic function, (b) a quadratic holomorphic function, and (c) an exponential holomorphic function, as regards the dependence of inflation and PBH production upon parameters of those functions and initial conditions, as well as verify viability of inflation with our superpotentials. We find that an efficient production of PBH consistent with cosmic microwave background measurements is only possible in the second (b) case. We calculate the masses of the produced PBH and find that they are below the Hawking (black hole) evaporation limit, so that they cannot be part of the current dark matter in our Universe.

Suitability of magnetic microbolometers based on paramagnetic temperature sensors for CMB polarization measurements

High resolution maps of polarization anisotropies of the Cosmic Microwave Background (CMB) are in high demand, since the discovery of primordial B-Modes in the polarization patterns would confirm the inflationary phase of the Universe that would have taken place before the last scattering of the CMB at the recombination epoch. Transition Edge Sensors (TES) and Microwave Kinetic Inductance Detectors (MKID) are the predominant detector technologies of cryogenic detector array based CMB instruments that search for primordial B-Modes. In this paper we propose another type of cryogenic detector to be used for CMB survey: A magnetic microbolometer (MMB) that is based on a paramagnetic temperature sensor. It is an adaption of state-of-the-art metallic magnetic calorimeters (MMCs) that are meanwhile a key technology for high resolution $\alpha$, $\beta$, $\gamma$ and X-ray spectroscopy as well as the study of neutrino mass. The effort to adapt MMCs for CMB surveys is triggered by their lack of Johnson noise associated with the detector readout, the possibility of straightforward calibration and higher dynamic range given it possesses a broad and smooth responsivity dependence with temperature and the absence of Joule dissipation which simplifies the thermal design. A brief proof of concept case study is analyzed, taking into account typical constraints in CMB measurements and reliable microfabrication processes. The results show that MMBs provide a promising technology for CMB polarization survey as their sensitivity can be tuned for background limited detection of the sky while simultaneously maintaining a low time response to avoid distortion of the point-source response of the telescope. As the sensor technology and its fabrication techniques are compatible with TES based bolometric detector arrays, a change of detector technology would even come with very low cost.

Hubble Tension: The Evidence of New Physics

The ΛCDM model provides a good fit to most astronomical observations but harbors large areas of phenomenology and ignorance. With the improvements in the precision and number of observations, discrepancies between key cosmological parameters of this model have emerged. Among them, the most notable tension is the 4σ to 6σ deviation between the Hubble constant (H0) estimations measured by the local distance ladder and the cosmic microwave background (CMB) measurement. In this review, we revisit the H0 tension based on the latest research and sort out evidence from solutions to this tension that might imply new physics beyond the ΛCDM model. The evidence leans more towards modifying the late-time universe.

A grounded perspective on new early dark energy using ACT, SPT, and BICEP/Keck

We examine further the ability of the New Early Dark Energy model (NEDE) to resolve the current tension between the Cosmic Microwave Background (CMB) and local measurements of H 0 and the consequences for inflation. We perform new Bayesian analyses, including the current datasets from the ground-based CMB telescopes Atacama Cosmology Telescope (ACT), the South Pole Telescope (SPT), and the BICEP/Keck telescopes, employing an updated likelihood for the local measurements coming from the SH 0ES collaboration. Using the SH 0ES prior on H 0, the combined analysis with Baryonic Acoustic Oscillations (BAO), Pantheon, Planck and ACT improves the best-fit by Δχ 2 = -15.9 with respect to ΛCDM, favors a non-zero fractional contribution of NEDE, fNEDE > 0, by 4.8σ, and gives a best-fit value for the Hubble constant of H 0 = 72.09 km/s/Mpc (mean 71.49 ± 0.82 with 68% C.L.). A similar analysis using SPT instead of ACT yields consistent results with a Δχ 2 = -23.1 over ΛCDM, a preference for non-zero f NEDE of 4.7σ and a best-fit value of H0 = 71.77 km/s/Mpc (mean 71.43 ± 0.85 with 68% C.L.). We also provide the constraints on the inflation parameters r and ns coming from NEDE, including the BICEP/Keck 2018 data, and show that the allowed upper value on the tensor-scalar ratio is consistent with the ΛCDM bound, but, as also originally found, with a more blue scalar spectrum implying that the simplest curvaton model is now favored over the Starobinsky inflation model.