ALMA finds dew drops in the dusty spider’s web

We present 0.̋5 resolution ALMA detections of the observed 246 GHz continuum, [CI] 3P2→3P1 fine structure line ([CI]2–1), CO(7–6), and H2O lines in the z = 2.161 radio galaxy MRC1138-262, the so-called Spiderweb galaxy. We detect strong [CI]2–1 emission both at the position of the radio core, and in a second component ~4 kpc away from it. The 1100 km s-1 broad [CI]2–1 line in this latter component, combined with its H2 mass of 1.6 × 1010 M⊙, implies that this emission must come from a compact region <60 pc, possibly containing a second active galactic nucleus (AGN). The combined H2 mass derived for both objects, using the [CI]2–1 emission, is 3.3 × 1010 M⊙. The total CO(7–6)/[CI]2–1 line flux ratio of 0.2 suggests a low excitation molecular gas reservoir and/or enhanced atomic carbon in cosmic ray dominated regions. We detect spatially-resolved H2O 211−202 emission – for the first time in a high-z unlensed galaxy – near the outer radio lobe to the east, and near the bend of the radio jet to the west of the radio galaxy. No underlying 246 GHz continuum emission is seen at either position. We suggest that the H2O emission is excited in the cooling region behind slow (10–40 km s-1) shocks in dense molecular gas (103−5 cm-3). The extended water emission is likely evidence of the radio jet’s impact on cooling and forming molecules in the post-shocked gas in the halo and inter-cluster gas, similar to what is seen in low-z clusters and other high-z radio galaxies. These observations imply that the passage of the radio jet in the interstellar and inter-cluster medium not only heats gas to high temperatures, as is commonly assumed or found in simulations, but also induces cooling and dissipation, which can lead to substantial amounts of cold dense molecular gas. The formation of molecules and strong dissipation in the halo gas of MRC1138-262 may explain both the extended diffuse molecular gas and the young stars observed around MRC1138-262

3D tomography of the giant Lyα nebulae of z ≈ 3–5 radio-loud AGN

Lyα emission nebulae are ubiquitous around high-redshift galaxies and are tracers of the gaseous environment on scales out to ≳100 pkpc (proper kiloparsec). High-redshift radio galaxies (HzRGs, type-2 radio-loud quasars) host large-scale nebulae observed in the ionised gas differ from those seen in other types of high-redshift quasars. In this work, we exploit MUSE observations of Lyα nebulae around eight HzRGs (2.92 < z < 4.51). All of the HzRGs have large-scale Lyα emission nebulae with seven of them extended over 100 pkpc at the observed surface brightness limit (∼2 − 20 × 10−19 erg s−1 cm−2 arcsec−2). Because the emission line profiles are significantly affected by neutral hydrogen absorbers across the entire nebulae extent, we performed an absorption correction to infer maps of the intrinsic Lyα surface brightness, central velocity, and velocity width, all at the last scattering surface of the observed Lyα photons. We find the following: (i) that the intrinsic surface brightness radial profiles of our sample can be described by an inner exponential profile and a power law in the low luminosity extended part; (ii) our HzRGs have a higher surface brightness and more asymmetric nebulae than both radio-loud and radio-quiet type-1 quasars; (iii) intrinsic nebula kinematics of four HzRGs show evidence of jet-driven outflows but we find no general trends for the whole sample; (iv) a relation between the maximum spatial extent of the Lyα nebula and the projected distance between the active galactic nuclei (AGN) and the centroids of the Lyα nebula; and (v) an alignment between radio jet position angles and the Lyα nebula morphology. All of these findings support a scenario in which the orientation of the AGN has an impact on the observed nebular morphologies and resonant scattering may affect the shape of the surface brightness profiles, nebular kinematics, and relations between the observed Lyα morphologies. Furthermore, we find evidence showing that the outskirts of the ionised gas nebulae may be ‘contaminated’ by Lyα photons from nearby emission halos and that the radio jet affects the morphology and kinematics of the nebulae. Overall, this work provides results that allow us to compare Lyα nebulae around various classes of quasars at and beyond cosmic noon (z ∼ 3)

SARS-CoV-2 antibody prevalence among homeless people and shelter workers in Denmark:a nationwide cross-sectional study

BACKGROUND: People experiencing homelessness (PEH) and associated shelter workers may be at higher risk of infection with “Severe acute respiratory syndrome coronavirus 2” (SARS-CoV-2). The aim of this study was to determine the prevalence of SARS-CoV-2 among PEH and shelter workers in Denmark. DESIGN AND METHODS: In November 2020, we conducted a nationwide cross-sectional seroprevalence study among PEH and shelter workers at 21 recruitment sites in Denmark. The assessment included a point-of-care test for antibodies against SARS-CoV-2, followed by a questionnaire. The seroprevalence was compared to that of geographically matched blood donors considered as a proxy for the background population, tested using a total Ig ELISA assay. RESULTS: We included 827 participants in the study, of whom 819 provided their SARS-CoV-2 antibody results. Of those, 628 were PEH (median age 50.8 (IQR 40.9–59.1) years, 35.5% female) and 191 were shelter workers (median age 46.6 (IQR 36.1–55.0) years and 74.5% female). The overall seroprevalence was 6.7% and was similar among PEH and shelter workers (6.8% vs 6.3%, p = 0.87); and 12.2% among all participants who engaged in sex work. The overall participant seroprevalence was significantly higher than that of the background population (2.9%, p < 0.001). When combining all participants who reported sex work or were recruited at designated safe havens, we found a significantly increased risk of seropositivity compared to other participants (OR 2.23, 95%CI 1.06–4.43, p = 0.02). Seropositive and seronegative participants reported a similar presence of at least one SARS-CoV-2 associated symptom (49% and 54%, respectively). INTERPRETATIONS: The prevalence of SARS-CoV-2 antibodies was more than twice as high among PEH and associated shelter workers, compared to the background population. These results could be taken into consideration when deciding in which phase PEH are eligible for a vaccine, as part of the Danish national SARS-CoV-2 vaccination program rollout. FUNDING: TrygFonden and HelseFonden. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-022-13642-7

The mysterious morphology of MRC0943-242 as revealed by ALMA and MUSE

© 2016 ESO. We present a pilot study of the z = 2.923 radio galaxy MRC0943-242, where we combine information from ALMA and MUSE data cubes for the first time. Even with modest integration times, we disentangle the AGN and starburst dominated components. These data reveal a highly complex morphology as the AGN, starburst, and molecular gas components show up as widely separated sources in dust continuum, optical continuum, and CO line emission observations. CO(1-0) and CO(8-7) line emission suggest that there is a molecular gas reservoir offset from both the dust and the optical continuum that is located ~90 kpc from the AGN. The UV line emission has a complex structure in emission and absorption. The line emission is mostly due to a large scale ionisation cone energised by the AGN, and a Lya emitting bridge of gas between the radio galaxy and a heavily star-forming set of components. Strangely, the ionisation cone has no Lya emission. We find this is due to an optically thick layer of neutral gas with unity covering fraction spread out over a region of at least ~100 kpc from the AGN. Other less thick absorption components are associated with Lya emitting gas within a few tens of kpc from the radio galaxy and are connected by a bridge of emission. We speculate that this linear structure of dust, Lya and CO emission, and the redshifted absorption seen in the circum nuclear region may represent an accretion flow feeding gas into this massive AGN host galaxy

Long-Term Benefits from Early Antiretroviral Therapy Initiation in HIV Infection

BACKGROUND: For people with HIV and CD4+ counts >500 cells/mm3, early initiation of antiretroviral therapy (ART) reduces serious AIDS and serious non-AIDS (SNA) risk compared with deferral of treatment until CD4+ counts are 500 cells/mm3, excess risk of AIDS and SNA associated with delaying treatment initiation was diminished after ART initiation, but persistent excess risk remained. (Funded by the National Institute of Allergy and Infectious Diseases and others.)

The RAdio Galaxy Environment Reference Survey (RAGERS) : Evidence of an anisotropic distribution of submillimeter galaxies in the 4C 23.56 protocluster at z=2.48

High-redshift radio(-loud) galaxies (H$z$RGs) are massive galaxies with powerful radio-loud active galactic nuclei (AGNs) and serve as beacons for protocluster identification. However, the interplay between H$z$RGs and the large-scale environment remains unclear. To understand the connection between H$z$RGs and the surrounding obscured star formation, we investigated the overdensity and spatial distribution of submillimeter-bright galaxies (SMGs) in the field of 4C\,23.56, a well-known H$z$RG at $z=2.48$. We used SCUBA-2 data ($\sigma\,{\sim}\,0.6$\,mJy) to estimate the $850\,{\rm \mu m}$ source number counts and examine the radial and azimuthal overdensities of the $850\,{\rm \mu m}$ sources in the vicinity of the H$z$RG. The angular distribution of SMGs is inhomogeneous around the H$z$RG 4C\,23.56, with fewer sources oriented along the radio jet. We also find a significant overdensity of bright SMGs (${\rm S}_{850\rm\,\mu m}\geq5\,$mJy). Faint and bright SMGs exhibit different spatial distributions. The former are concentrated in the core region, while the latter prefer the outskirts of the H$z$RG field. High-resolution observations show that the seven brightest SMGs in our sample are intrinsically bright, suggesting that the overdensity of bright SMGs is less likely due to the source multiplicity