Abstract
We construct the largest curved-sky galaxy weak lensing mass map to date from the DES first-year (DES Y1) data. The map, about 10 times larger than the previous work, is constructed over a ...contiguous ≈1500 deg2, covering a comoving volume of ≈10 Gpc3. The effects of masking, sampling, and noise are tested using simulations. We generate weak lensing maps from two DES Y1 shear catalogues, MetaCalibration and Im3shape, with sources at redshift 0.2 < z < 1.3, and in each of four bins in this range. In the highest signal-to-noise map, the ratio between the mean signal to noise in the E-mode map and the B-mode map is ∼1.5 (∼2) when smoothed with a Gaussian filter of σG = 30 (80) arcmin. The second and third moments of the convergence κ in the maps are in agreement with simulations. We also find no significant correlation of κ with maps of potential systematic contaminants. Finally, we demonstrate two applications of the mass maps: (1) cross-correlation
with different foreground tracers of mass and (2) exploration of the largest peaks and voids in the maps.
We describe the creation, content, and validation of the Dark Energy Survey (DES) internal year-one cosmology data set, Y1A1 GOLD, in support of upcoming cosmological analyses. The Y1A1 GOLD data set ...is assembled from multiple epochs of DES imaging and consists of calibrated photometric zero-points, object catalogs, and ancillary data products-e.g., maps of survey depth and observing conditions, star-galaxy classification, and photometric redshift estimates-that are necessary for accurate cosmological analyses. The Y1A1 GOLD wide-area object catalog consists of million objects detected in co-added images covering in the DES grizY filters. The 10 limiting magnitude for galaxies is , , , , and . Photometric calibration of Y1A1 GOLD was performed by combining nightly zero-point solutions with stellar locus regression, and the absolute calibration accuracy is better than 2% over the survey area. DES Y1A1 GOLD is the largest photometric data set at the achieved depth to date, enabling precise measurements of cosmic acceleration at z 1.
We established a collection of 7,000 transgenic lines of Drosophila melanogaster. Expression of GAL4 in each line is controlled by a different, defined fragment of genomic DNA that serves as a ...transcriptional enhancer. We used confocal microscopy of dissected nervous systems to determine the expression patterns driven by each fragment in the adult brain and ventral nerve cord. We present image data on 6,650 lines. Using both manual and machine-assisted annotation, we describe the expression patterns in the most useful lines. We illustrate the utility of these data for identifying novel neuronal cell types, revealing brain asymmetry, and describing the nature and extent of neuronal shape stereotypy. The GAL4 lines allow expression of exogenous genes in distinct, small subsets of the adult nervous system. The set of DNA fragments, each driving a documented expression pattern, will facilitate the generation of additional constructs for manipulating neuronal function.
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► Seven thousand GAL4 lines are made using defined enhancer fragments and integration site ► Expression patterns of 6,650 lines are imaged in the adult brain and VNC ► The fly brain displays limited left-right asymmetry ► GAL4 lines and high-resolution image data are available to the community
Rubin and colleagues have established a collection of 7,000 GAL4 driver lines in Drosophila. A different, defined fragment of genomic DNA serves as a transcriptional enhancer to control GAL4 expression in each line. The authors describe the expression patterns driven by each fragment in the adult brain and ventral nerve cord and illustrate the utility of these data in identifying novel neuronal cell types, revealing brain asymmetry, and describing the nature and extent of neuronal shape stereotypy.
Pure and Y-doped SnO2 hollow nanofibers with porous structures were fabricated via electrospinning technique and calcination procedure. The porous SnO2 hollow nanofibers were characterized by ...scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) and X-ray photoelectron spectroscopy (XPS). Acetone sensing properties of the hollow nanofibers were also investigated. The surface morphology of pure SnO2 and Y-doped SnO2 possessed a hollow nanostructure with rough porous surface after being annealed at 600°C, and the diameters of the nanofibers were in the range of 154–200nm. The BET surface area measurement further indicated that the surface textural was mesoporous, and the pore size was calculated above 24nm by Barret–Joyner–Halenda (BJH). Gas sensing properties revealed that Y-doped SnO2 hollow nanofibers exhibited a much higher response to acetone vapor than pure SnO2 hollow nanofibers at 300°C. Y-doped SnO2 hollow nanofibers exhibited good stability and excellent selectivity, which were ascribed to the 1D hollow nanostructure and the effect of Y doping. The formation mechanism and the acetone sensing mechanism of SnO2 hollow nanofibers were also discussed.
We use 26×106 galaxies from the Dark Energy Survey (DES) Year 1 shape catalogs over 1321 deg2 of the sky to produce the most significant measurement of cosmic shear in a galaxy survey to date. We ...constrain cosmological parameters in both the flat ΛCDM and the wCDM models, while also varying the neutrino mass density. These results are shown to be robust using two independent shape catalogs, two independent photo-z calibration methods, and two independent analysis pipelines in a blind analysis. We find a 3.5% fractional uncertainty on σ8(Ωm/0.3)0.5=0.782−0.027+0.027 at 68% C.L., which is a factor of 2.5 improvement over the fractional constraining power of our DES Science Verification results. In wCDM, we find a 4.8% fractional uncertainty on σ8(Ωm/0.3)0.5=0.777−0.038+0.036 and a dark energy equation-of-state w=−0.95−0.39+0.33. We find results that are consistent with previous cosmic shear constraints in σ8-Ωm, and we see no evidence for disagreement of our weak lensing data with data from the cosmic microwave background. Finally, we find no evidence preferring a wCDM model allowing w≠−1. We expect further significant improvements with subsequent years of DES data, which will more than triple the sky coverage of our shape catalogs and double the effective integrated exposure time per galaxy.
We perform a joint analysis of the counts and weak lensing signal of redMaPPer clusters selected from the Dark Energy Survey (DES) Year 1 dataset. Our analysis uses the same shear and source ...photometric redshifts estimates as were used in the DES combined probes analysis. Our analysis results in surprisingly low values for S8 = σ8 (Ωm/0.3)0.5 = 0.65 ± 0.04, driven by a low matter density parameter, Ωm = 0.179+0.031−0.038, with σ8 − Ωm posteriors in 2.4σ tension with the DES Y1 3x2pt results, and in 5.6σ with the Planck CMB analysis. These results include the impact of post-unblinding changes to the analysis, which did not improve the level of consistency with other data sets compared to the results obtained at the unblinding. The fact that multiple cosmological probes (supernovae, baryon acoustic oscillations, cosmic shear, galaxy clustering and CMB anisotropies), and other galaxy cluster analyses all favor significantly higher matter densities suggests the presence of systematic errors in the data or an incomplete modeling of the relevant physics. Cross checks with x-ray and microwave data, as well as independent constraints on the observable-mass relation from Sunyaev-Zeldovich selected clusters, suggest that the discrepancy resides in our modeling of the weak lensing signal rather than the cluster abundance. Repeating our analysis using a higher richness threshold (λ ≥ 30) significantly reduces the tension with other probes, and points to one or more richness-dependent effects not captured by our model.
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