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In this follow-up analysis, we update previous constraints on the transitional Planck mass (TPM) modified gravity model using the latest version of EFTCAMB and provide new constraints using South Pole Telescope (SPT) and Planck anisotropy data along with Planck cosmic microwave background lensing, baryon acoustic oscillations, and Type Ia supernovae data and a Hubble constant,H₀, prior from local measurements. We find that large shifts in the Planck mass lead to large suppression of power on small scales that is disfavored by both the SPT and Planck data. Using only the SPT temperature-polarization–polarization-polarization (TE-EE) data, this suppression of power can be compensated for by an upward shift of the scalar index ton_s= 1.003 ± 0.016, resulting in$H_0={71.94}_{-0.85}^{+0.86}$km m⁻¹Mpc⁻¹and a ∼7% shift in the Planck mass. Including the Planck temperature-temperature (TT) ℓ≤ 650 and Planck TE-EE data restricts the shift to be <5% at 2σwithH₀= 70.65 ± 0.66 km m⁻¹Mpc⁻¹. Excluding theH₀prior, the SPT and Planck data constrain the shift in the Planck mass to be <3% at 2σwith a best-fit value of 0.04%, consistent with the Λ cold dark matter limit. In this case$H_0={69.09}_{-0.68}^{+0.69}$km s⁻¹Mpc⁻¹, which is partially elevated by the dynamics of the scalar field in the late Universe. This differs from early dark energy models that prefer higher values ofH₀when the high-ℓPlanck TT data are excluded. We additionally constrain TPM using redshift space distortion data from BOSS DR12 and cosmic shear, galaxy–galaxy lensing, and galaxy clustering data from DES Y1, finding both disfavor transitions close to recombination, but earlier Planck mass transitions are allowed.

 

Abstract CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the universe. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semianalytic projection tool, targeted explicitly toward optimizing constraints on the tensor-to-scalar ratio, r , in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2–3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments, given a desired scientific goal. To form a closed-loop process, we couple this semianalytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for r > 0.003 at greater than 5 σ , or in the absence of a detection, of reaching an upper limit of r < 0.001 at 95% CL. 

In this paper, we probe the hot, post-shock gas component of quasar-driven winds through the thermal Sunyaev–Zel’dovich (tSZ) effect. Combining data sets from the Atacama Cosmology Telescope, the Herschel Space Observatory, and the Very Large Array, we measure average spectral energy distributions of 109 829 optically selected, radio quiet quasars from 1.4 to 3000 GHz in six redshift bins between 0.3 < z < 3.5. We model the emission components in the radio and far-infrared, plus a spectral distortion from the tSZ effect. At z > 1.91, we measure the tSZ effect at 3.8σ significance with an amplitude corresponding to a total thermal energy of 3.1 × 1060 erg. If this energy is due to virialized gas, then our measurement implies quasar host halo masses are ∼6 × 1012 h−1 M⊙. Alternatively, if the host dark matter halo masses are ∼2 × 1012 h−1 M⊙ as some measurements suggest, then we measure a >90 per cent excess in the thermal energy over that expected due to virialization. If the measured SZ effect is primarily due to hot bubbles from quasar-driven winds, we find that $(5^{+1.2}_{-1.3}$) per cent of the quasar bolometric luminosity couples to the intergalactic medium over a fiducial quasar lifetime of 100 Myr. An additional source of tSZ may be correlated structure, and further work is required to separate the contributions. At z ≤ 1.91, we detect emission at 95 and 148 GHz that is in excess of thermal dust and optically thin synchrotron emission. We investigate potential sources of this excess emission, finding that CO line emission and an additional optically thick synchrotron component are the most viable candidates.