We present a method for measuring the masses of galaxy clusters using the imprint of their gravitational lensing signal on the cosmic microwave background (CMB) temperature anisotropies. The method ...first reconstructs the projected gravitational potential with a quadratic estimator and then applies a matched filter to extract cluster mass. The approach is well-suited for statistical analyses that bin clusters according to other mass proxies. We find that current experiments, such as Planck, the South Pole Telescope and the Atacama Cosmology Telescope, can practically implement such a statistical methodology, and that future experiments will reach sensitivities sufficient for individual measurements of massive systems. As illustration, we use simulations of Planck observations to demonstrate that it is possible to constrain the mass scale of a set of 62 massive clusters with prior information from X-ray observations, similar to the published Planck ESZ-XMM sample. We examine the effect of the thermal (tSZ) and kinetic (kSZ) Sunyaev-Zeldovich (SZ) signals, finding that the impact of the kSZ remains small in this context. The stronger tSZ signal, however, must be actively removed from the CMB maps by component separation techniques prior to reconstruction of the gravitational potential. Our study of two such methods highlights the importance of broad frequency coverage for this purpose. A companion paper presents application to the Planck data on the ESZ-XMM sample.
We look for signatures of the Hu-Sawicki f ( R ) modified gravity theory proposed to explain the observed accelerated expansion of the Universe in observations of the galaxy distribution, the cosmic ...microwave background (CMB), and gravitational lensing of the CMB. We study constraints obtained using observations of only the CMB primary anisotropies before adding the galaxy power spectrum and its cross-correlation with CMB lensing. We show that cross-correlation of the galaxy distribution with lensing measurements is crucial in order to break parameter degeneracies, placing tighter constraints on the model. In particular, we set a strong upper limit on log| f R 0 |< − 4.61 at 95% confidence level. This means that while the model may explain the accelerated expansion, its impact on large-scale structure closely resembles general relativity (GR). This analysis is the first to make use of the galaxy clustering, CMB lensing, and their cross-correlation power spectra to constrain Hu-Sawicki f ( R ) gravity. Restricting the analysis to the linear regime, we place a robust constraint that is competitive with other cosmological studies whilst using fewer probes. This study can be seen as a precursor to cross-correlation analyses of f ( R ) gravity and can be repeated with next-stage surveys, which will benefit from lower noise and hence probe smaller potential deviations from GR.
The halo mass function (HMF) is a critical element in cosmological analyses of galaxy cluster catalogs. We quantify the impact of uncertainties in HMF parameters on cosmological constraints from ...cluster catalogs similar to those from
Planck
, those expected from the
Euclid
, Roman, and
Rubin
surveys, and from a hypothetical larger future survey. We analyze simulated catalogs in each case, gradually loosening priors on HMF parameters to evaluate the degradation in cosmological constraints. While current uncertainties on HMF parameters do not substantially impact
Planck
-like surveys, we find that they can significantly degrade the cosmological constraints for a
Euclid
-like survey. Consequently, the current precision on the HMF is not sufficient for
Euclid
, Roman,
Rubin
or possible larger surveys. Future experiments will have to properly account for uncertainties in HMF parameters, and it will be necessary to improve the precision of HMF fits to avoid weakening constraints on cosmological parameters.
Galaxies, diffuse gas, and dark matter make up the cosmic web that defines the large-scale structure of the Universe. We constrained the joint distribution of these constituents by cross-correlating ...galaxy samples binned by stellar mass from the Sloan Digital Sky Survey CMASS catalog with maps of lensing convergence and the thermal Sunyaev-Zeldovich (tSZ) effect from the
Planck
mission. Fitting a halo-based model to our measured angular power spectra (galaxy-galaxy, galaxy-lensing convergence, and galaxy-tSZ) at a median redshift of
z
= 0.53, we detected variation with stellar mass of the galaxy satellite fraction and galaxy spatial distribution within host halos. We find a tSZ-halo hydrostatic mass bias,
b
h
, such that (1 −
b
h
) = 0.6 ± 0.05, with a hint of a larger bias,
b
h
, at the high stellar mass end. The normalization of the galaxy-cosmic microwave background lensing convergence cross-power spectrum shows that galaxies trace the matter distribution without an indication of stochasticity (
A
= 0.98 ± 0.09). We forecast that next-generation cosmic microwave background experiments will improve the constraints on the hydrostatic bias by a factor of two and will be able to constrain the small-scale distribution of dark matter, hence informing the theory of feedback processes.
We compare the Planck Sunyaev–Zeldovich (SZ) cluster sample (PSZ1) to the Sloan Digital Sky Survey (SDSS) redMaPPer catalogue, finding that all Planck clusters within the redMaPPer mask and within ...the redshift range probed by redMaPPer are contained in the redMaPPer cluster catalogue. These common clusters define a tight scaling relation in the richness-SZ mass (λ–M
SZ) plane, with an intrinsic scatter in richness of
$\sigma _{\lambda |M_{{\rm SZ}}} = 0.266 \pm 0.017$
. The corresponding intrinsic scatter in true cluster halo mass at fixed richness is ≈21 per cent. The regularity of this scaling relation is used to identify failures in both catalogues. The failure rates for redMaPPer and PSZ1 1.2 per cent and 14.7 per cent, respectively. The PSZ1 failure rates decreases to 9.8 per cent after removing incorrect redshifts that were drawn from the literature. We note the failure rates in the PSZ1 from this analysis are specific to the SDSS overlap region, and may not be indicative of failure rates over the full Planck survey. We have further identified five PSZ1 sources that suffer from projection effects (multiple rich systems along the line of sight of the SZ detection) and 17 new high-redshift (z ≳ 0.6) cluster candidates of varying degrees of confidence.
ABSTRACT
We present weak lensing mass estimates for a sample of 458 galaxy clusters from the redMaPPer Sloan Digital Sky Survey DR8 catalogue using Hyper Suprime-Cam weak lensing data. We develop a ...method to quickly estimate cluster masses from weak lensing shear and use this method to estimate weak lensing masses for each of the galaxy clusters in our sample. Subsequently, we constrain the mass–richness relation as well as the intrinsic scatter between the cluster richness and the measured weak lensing masses. When calculating the mass–richness relation for all clusters with a richness λ > 20, we find a tension in the slope of the mass–richness relation with the Dark Energy Survey Year 1 stacked weak lensing analysis. For a reduced sample of clusters with a richness λ > 40, our results are consistent with the Dark Energy Survey Year 1 analysis.
To determine if inhaled and intranasal ciclesonide are superior to placebo at decreasing respiratory symptoms in adult outpatients with covid-19.
Randomised, double blind, placebo controlled trial.
...Three Canadian provinces (Quebec, Ontario, and British Columbia).
203 adults aged 18 years and older with polymerase chain reaction confirmed covid-19, presenting with fever, cough, or dyspnoea.
Participants were randomised to receive either inhaled ciclesonide (600 μg twice daily) and intranasal ciclesonide (200 μg daily) or metered dose inhaler and nasal saline placebos for 14 days.
The primary outcome was symptom resolution at day 7. Analyses were conducted on the modified intention-to-treat population (participants who took at least one dose of study drug and completed one follow-up survey) and adjusted for stratified randomisation by sex.
The modified intention-to-treat population included 203 participants: 105 were randomly assigned to ciclesonide (excluding two dropouts and one loss to follow-up) and 98 to placebo (excluding three dropouts and six losses to follow-up). The median age was 35 years (interquartile range 27-47 years) and 54% were women. The proportion of participants with resolution of symptoms by day 7 did not differ significantly between the intervention group (42/105, 40%) and control group (34/98, 35%); absolute adjusted risk difference 5.5% (95% confidence interval -7.8% to 18.8%). Results might be limited to the population studied, which mainly included younger adults without comorbidities. The trial was stopped early, therefore could have been underpowered.
Compared with placebo, the combination of inhaled and intranasal ciclesonide did not show a statistically significant increase in resolution of symptoms among healthier young adults with covid-19 presenting with prominent respiratory symptoms. As evidence is insufficient to determine the benefit of inhaled and intranasal corticosteroids in the treatment of covid-19, further research is needed.
ClinicalTrials.gov NCT04435795.
The abundance of peaks in weak gravitational lensing maps is a potentially powerful cosmological tool, complementary to measurements of the shear power spectrum. We study peaks detected directly in ...shear maps, rather than convergence maps, an approach that has the advantage of working directly with the observable quantity, the galaxy ellipticity catalog. Using large numbers of numerical simulations to accurately predict the abundance of peaks and their covariance, we quantify the cosmological constraints attainable by a large-area survey similar to that expected from the Euclid mission, focusing on the density parameter, Ωm, and on the power spectrum normalization, σ8, for illustration. We present a tomographic peak counting method that improves the conditional (marginal) constraints by a factor of 1.2 (2) over those from a two-dimensional (i.e., non-tomographic) peak-count analysis. We find that peak statistics provide constraints an order of magnitude less accurate than those from the cluster sample in the ideal situation of a perfectly known observable-mass relation; however, when the scaling relation is not known a priori, the shear-peak constraints are twice as strong and orthogonal to the cluster constraints, highlighting the value of using both clusters and shear-peak statistics.
A 2-dose series of recombinant zoster vaccine (RZV) was 97% effective against herpes zoster (HZ) in a pivotal clinical trial.
To evaluate real-world effectiveness of RZV against HZ.
Prospective ...cohort study.
Four health care systems in the Vaccine Safety Datalink.
Persons aged 50 years or older.
The outcome was incident HZ defined by a diagnosis with an antiviral prescription. Cox regression was used to estimate the hazard of HZ in vaccinated persons compared with unvaccinated persons, with adjustment for covariates. Vaccine effectiveness (VE) was calculated as 1 minus the adjusted hazard ratio and was estimated by time since the last RZV dose and by corticosteroid use.
The study included nearly 2.0 million persons who contributed 7.6 million person-years of follow-up. After adjustment, VE of 1 dose was 64% and VE of 2 doses was 76%. After 1 dose only, VE was 70% during the first year, 45% during the second year, 48% during the third year, and 52% after the third year. After 2 doses, VE was 79% during the first year, 75% during the second year, and 73% during the third and fourth years. Vaccine effectiveness was 65% in persons who received corticosteroids before vaccination and 77% in those who did not.
Herpes zoster could not be identified as accurately in these observational data as in the previous clinical trials.
Two doses of RZV were highly effective, although less effective than in the previous clinical trials. Two-dose effectiveness waned very little during the 4 years of follow-up. However, 1-dose effectiveness waned substantially after 1 year, underscoring the importance of the second dose.
Centers for Disease Control and Prevention.
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