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The scattering of cosmic microwave background (CMB) photons off the free-electron gas in galaxies and clusters leaves detectable imprints on high resolution CMB maps: the thermal and kinematic Sunyaev-Zel'dovich effects (tSZ and kSZ respectively). We use combined microwave maps from the Atacama Cosmology Telescope DR5 and Planck in combination with the CMASS (mean redshift ⟨z

The thermal and kinematic Sunyaev-Zel'dovich effects (tSZ, kSZ) probe the thermodynamic properties of the circumgalactic and intracluster medium (CGM and ICM) of galaxies, groups, and clusters, since they are proportional, respectively, to the integrated electron pressure and momentum along the line of sight. We present constraints on the gas thermodynamics of CMASS (constant stellar mass) galaxies in the Baryon Oscillation Spectroscopic Survey using new measurements of the kSZ and tSZ signals obtained in a companion paper [Schaan et al.]. Combining kSZ and tSZ measurements, we measure within our model the amplitude of energy injection ϵM⋆c2, where M⋆ is the stellar mass, to be ϵ=(40±9)×10-6, and the amplitude of the nonthermal pressure profile to be αNth

We construct cosmic microwave background lensing mass maps using data from the 2014 and 2015 seasons of observations with the Atacama Cosmology Telescope (ACT). These maps cover 2100 square degrees of sky and overlap with a wide variety of optical surveys. The maps are signal dominated on large scales and have fidelity such that their correlation with the cosmic infrared background is clearly visible by eye. We also create lensing maps with thermal Sunyaev-Zel'dovich contamination removed using a novel cleaning procedure that only slightly degrades the lensing signal-to-noise ratio. The cross-spectrum between the cleaned lensing map and the BOSS CMASS galaxy sample is detected at 10σ significance, with an amplitude of A = 1.02 ± 0.10 relative to the Planck best-fitting Lambda cold dark matter cosmological model with fiducial linear galaxy bias. Our measurement lays the foundation for lensing cross-correlation science with current ACT data and beyond.

We use gravitational lensing of the cosmic microwave background (CMB) to measure the mass of the most distant blindly selected sample of galaxy clusters on which a lensing measurement has been performed to date. In CMB data from the the Atacama Cosmology Telescope and the Planck satellite, we detect the stacked lensing effect from 677 near-infrared-selected galaxy clusters from the Massive and Distant Clusters of WISE Survey (MaDCoWS), which have a mean redshift of zñ = 1.08. There are currently no representative optical weak lensing measurements of clusters that match the distance and average mass of this sample. We detect the lensing signal with a significance of 4.2s. We model the signal with a halo model framework to find the mean mass of the population from which these clusters are drawn. Assuming that the clusters follow Navarro–Frenk–White (NFW) density profiles, we infer a mean mass of M500cñ = (1.7 + 0.4) ´ 1014 M*. We consider systematic uncertainties from cluster redshift errors, centering errors, and the shape of the NFW profile. These are all smaller than 30% of our reported uncertainty. This work highlights the potential of CMB lensing to enable cosmological constraints from the abundance of distant clusters populating ever larger volumes of the observable universe, beyond the capabilities of optical weak lensing measurements.

We measure the projected number density profiles of galaxies and thesplashback feature in clusters selected by the Sunyaev--Zeldovich (SZ) effectfrom the Advanced Atacama Cosmology Telescope (AdvACT) survey using galaxiesobserved by the Dark Energy Survey (DES). The splashback radius for thecomplete galaxy sample is consistent with theoretical measurements fromCDM-only simulations, and is located at $2.4^{+0.3}_{-0.4}$ Mpc $h^{-1}$. Wesplit the sample based on galaxy color and find significant differences in theprofile shapes. Red galaxies and those in the green valley show asplashback-like minimum in their slope profile consistent with theoreticalpredictions, while the bluest galaxies show a weak feature that appears at asmaller radius. We develop a mapping of galaxies to subhalos in $N$-bodysimulations by splitting subhalos based on infall time onto the cluster halos.We find that the location of the steepest slope and differences in the shapesof the profiles can be mapped to differences in the average time of infall ofgalaxies of different colors. The minima of the slope in the galaxy profilestrace a discontinuity in the phase space of dark matter halos. By relatingspatial profiles to infall time for galaxies of different colours, we can usesplashback as a clock to understand galaxy quenching. We find that red galaxieshave on average been in their clusters for over $3.2 ~\rm Gyrs$, green galaxiesabout $2.2 ~\rm Gyrs$, while blue galaxies have been accreted most recently andhave not reached apocenter. Using the information from the complete radialprofiles, we fit a simple quenching model and find that the onset of galaxyquenching in clusters occurs after a delay of about a gigayear, and thatgalaxies quench rapidly thereafter with an exponential timescale of $0.6$ Gyr.

Optimal analyses of many signals in the cosmic microwave background (CMB) require map-level extraction of individual components in the microwave sky, rather than measurements at the power spectrum level alone. To date, nearly all map-level component separation in CMB analyses has been performed exclusively using satellite data. In this paper, we implement a component separation method based on the internal linear combination (ILC) approach which we have designed to optimally account for the anisotropic noise (in the 2D Fourier domain) often found in ground-based CMB experiments. Using this method, we combine multifrequency data from the Planck satellite and the Atacama Cosmology Telescope Polarimeter (ACTPol) to construct the first wide-area (≈2100 sq. deg.), arcminute-resolution component-separated maps of the CMB temperature anisotropy and the thermal Sunyaev-Zel'dovich (tSZ) effect sourced by the inverse-Compton scattering of CMB photons off hot, ionized gas. Our ILC pipeline allows for explicit deprojection of various contaminating signals, including a modified blackbody approximation of the cosmic infrared background (CIB) spectral energy distribution. The cleaned CMB maps will be a useful resource for CMB lensing reconstruction, kinematic SZ cross-correlations, and primordial non-Gaussianity studies. The tSZ maps will be used to study the pressure profiles of galaxies, groups, and clusters through cross-correlations with halo catalogs, with dust contamination controlled via CIB deprojection. The data products described in this paper are available on LAMBDA.