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Abstract We present the second data release of the Massive and Distant Clusters of WISE Survey 2 (MaDCoWS2). We expand from the equatorial first data release to most of the Dark Energy Camera Legacy Survey area, covering a total area of 6498 deg². The catalog consists of 133,036 signal-to-noise ratio (S/N) ≥ 5 galaxy cluster candidates at 0.1 ≤z≤ 2, including 6790 candidates atz> 1.5. We train a convolutional neural network (CNN) to identify spurious detections and include CNN-based cluster probabilities in the final catalog. We also compare the MaDCoWS2 sample with literature catalogs in the same area. The larger sample provides robust results that are consistent with our first data release. At S/N ≥ 5, we rediscover 59%–91% of clusters in existing catalogs that lie in the unmasked area of MC2. The median positional offsets are under 250 kpc, and the standard deviation of the redshifts is 0.031(1 +z). We fit a redshift-dependent power law to the relation between MaDCoWS2 S/N and observables from existing catalogs. Over the redshift ranges where the surveys overlap with MaDCoWS2, the lowest scatter is found between S/N and observables from optical/infrared surveys. We also assess the performance of our method using a mock light cone measuring purity and completeness as a function of cluster mass. The purity is above 90%, and we estimate the 50% completeness threshold at a virial mass of log(M/M_⊙) ≈ 14.3. The completeness estimate is uncertain due to the small number of massive halos in the light cone, but consistent with the recovery fraction found by comparing to other cluster catalogs. 

Abstract The evolution of galaxies depends on their masses and local environments; understanding when and how environmental quenching starts to operate remains a challenge. Furthermore, studies of the high-redshift regime have been limited to massive cluster members, owing to sensitivity limits or small fields of view when the sensitivity is sufficient, intrinsically biasing the picture of cluster evolution. In this work, we use stacking to investigate the average star formation history of more than 10,000 groups and clusters drawn from the Massive and Distant Clusters of WISE Survey 2. Our analysis covers near-ultraviolet to far-infrared wavelengths, for galaxy overdensities at 0.5 ≲z≲ 2.54. We employ spectral energy distribution fitting to measure the specific star formation rates (sSFRs) in four annular apertures with radii between 0 and 1000 kpc. Atz≳ 1.6, the average sSFR evolves similarly to the field in both the core and the cluster outskirts. Between $\overline{z}=1.60$and $\overline{z}=1.35$, the sSFR in the core drops sharply, and it continues to fall relative to the field sSFR at lower redshifts. We interpret this change as evidence that the impact of environmental quenching dramatically increases atz∼ 1.5, with the short time span of the transition suggesting that the environmental quenching mechanism dominant at this redshift operates on a rapid timescale. We find indications that the sSFR may decrease with increasing host halo mass, but lower-scatter mass tracers than the signal-to-noise ratio are needed to confirm this relationship. 

Abstract The Massive and Distant Clusters of WISE Survey 2 (MaDCoWS2) is a new survey designed as the successor of the original MaDCoWS survey. MaDCoWS2 improves upon its predecessor by using deeper optical and infrared data and a more powerful detection algorithm (PZWav). As input to the search, we usegrzphotometry from the DECam Legacy Survey (DECaLS) in combination with W1 and W2 photometry from the CatWISE2020 catalog to derive the photometric redshifts with full redshift probability distribution functions for Wide-field Infrared Survey Explorer (WISE)-selected galaxies. Cluster candidates are then detected using the PZWav algorithm to find three-dimensional galaxy overdensities from the sky positions and photometric redshifts. This paper provides the first MaDCoWS2 data release, covering 1461 (1838 without masking) deg²centered on the Hyper-SuprimeCam Subaru Strategic Program equatorial fields. Within this region, we derive a catalog of 22,970 galaxy cluster candidates detected at a signal-to-noise ratio (S/N) > 5. These clusters span the redshift range 0.1 <z< 2, including 1312 candidates atz> 1.5. We compare MaDCoWS2 to six existing catalogs in the area. We rediscover 60%–92% of the clusters in these surveys at S/N > 5. The medians of the absolute redshift offset are <0.02 relative to these surveys, while the standard deviations are less than 0.06. The median offsets between the detection position from MaDCoWS2 and other surveys are less than 0.25 Mpc. We quantify the relation between S/N and gas mass, total mass, luminosity, and richness from other surveys using a redshift-dependent power law relation. We find that the S/N-richness relation exhibits the lowest scatter. 

Abstract In this paper, we present the results of a blind survey for compact sources in 243 Galaxy clusters that were identified using the thermal Sunyaev–Zel'dovich effect (tSZ). The survey was carried out at 90 GHz using MUSTANG2 on the Green Bank Telescope and achieved a 5σdetection limit of 1 mJy in the center of each cluster. We detected 24 discrete sources. The majority (18) of these correspond to known radio sources, and of these, five show signs of significant variability, either with time or in spectral index. The remaining sources have no clear counterparts at other wavelengths. Searches for galaxy clusters via the tSZ strongly rely on observations at 90 GHz, and the sources found have the potential to bias mass estimates of clusters. We compare our results to the Websky simulation that can be used to estimate the source contamination in galaxy cluster catalogs. While the simulation shows a good match to our observations at the clusters’ centers, it does not match our source distribution further out. Sources over 104″ from a cluster’s center bias the tSZ signal high, for some of the sources found, by over 50%. When averaged over the whole cluster population, the effect is smaller but still at a level of 1%–2%. We also discovered that unlike previous measurements and simulations, we see an enhancement of source counts in the outer regions of the clusters and fewer sources than expected in the centers of this tSZ-selected sample. 

Abstract We present 150 MHz, 1.4 GHz, and 3 GHz radio imaging (LoTSS, FIRST, and VLASS) and spatially resolved ionized gas characteristics (SDSS IV-MaNGA) for 140 local ( z < 0.1) early-type red geyser galaxies. These galaxies have a low star formation activity (with a star formation rate, SFR, ∼ 0.01 M ⊙ yr −1 ), but show unique extended patterns in spatially resolved emission-line maps that have been interpreted as large-scale ionized winds driven by active galactic nuclei (AGN). In this work, we confirm that red geysers host low-luminosity radio sources ( L 1.4GHz ∼ 10 22 WHz −1 ). Out of 42 radio-detected red geysers, 32 are spatially resolved in LoTSS and FIRST, with radio sizes varying between ∼5–25 kpc. Three sources have radio sizes exceeding 40 kpc. A majority display a compact radio morphology and are consistent with either low-power compact radio sources (FR0 galaxies) or radio-quiet quasars. They may be powered by small-scale AGN-driven jets that remain unresolved at the current 5″ resolution of radio data. The extended radio sources, not belonging to the “compact” morphological class, exhibit steeper spectra with a median spectral index of −0.67, indicating the dominance of lobed components. The red geysers hosting extended radio sources also have the lowest specific SFRs, suggesting they either have a greater impact on the surrounding interstellar medium or are found in more massive halos on average. The degree of alignment of the ionized wind cone and the extended radio features are either 0° or 90°, indicating possible interaction between the interstellar medium and the central radio AGN.