Minkowski Functionals in Joint Galaxy Clustering & Weak Lensing Analyses

We investigate the inclusion of clustering maps in a weak lensing Minkowski functional (MF) analysis of DES-like and LSST-like simulations to constrain cosmological parameters. The standard 3x2pt approach to lensing and clustering data uses two-point correlations as its primary statistic; MFs, morphological statistics describing the shape of matter fields, provide additional information for non- Gaussian fields. Previous analyses have studied MFs of lensing convergence maps; in this project we explore their simultaneous application to clustering maps. We employ a simplified linear galaxy bias model, and using a lognormal curved sky measurement and Monte Carlo Markov Chain (MCMC) sampling process for parameter inference, we find that MFs do not yield any information in the Ωm – σ8 plane not already generated by a 3x2pt analysis. However, we expect that MFs should improve constraining power when nonlinear baryonic and other small-scale effects are taken into account. As with a 3x2pt analysis, we find a significant improvement to constraints when adding clustering data to MF-only and MF+C` shear measurements, and strongly recommend future higher order statistics be measured from both convergence and clustering maps.ISSN:2565-612

Cruise Report: EX-17-11 Gulf of Mexico 2017 (ROV and Mapping)

From November 29, 2017 to December 21, 2017, the NOAA Office of Ocean Exploration and Research (OER) and partners conducted a telepresence-enabled ocean exploration expedition on NOAA Ship Okeanos Explorer to collect critical baseline data and information and to improve knowledge about unexplored and poorly understood deepwater areas of the Gulf of Mexico. The Gulf of Mexico 2017 (EX-17-11) expedition was part of a series of expeditions between 2017 and 2018 that explored deepwater areas in the Gulf of Mexico. During 23 days at sea, 17 remotely operated vehicle (ROV) dives were completed off the Western Florida Escarpment and in the central and western Gulf of Mexico. Over 93 hours of ROV bottom time were logged at depths between 300 and 2,321 meters. Over 20,000 square kilometers of seafloor were mapped. A total of 138 biological and 11 geological samples were collected. The expedition gathered over 280,000 live video views worldwide and the OER website received over 35,600 views. A core onshore science team of over 80 participants from around the world collaborated and supported real-time ocean exploration science. The data associated with this expedition have been archived and are publicly available through the NOAA Archives

Politicizing and humanizing management learning and education with Paulo Freire

Paulo Freire is widely acknowledged as one of the leading 20th-century philosophers of education. Freire’s ideas have been leveraged by scholars across the social sciences, including in the field of organization studies where it has come to inform extant understandings of management learning and education. While such engagements with Freire have enriched many germane discourses in our field, we have yet to excavate the full potential of his writings. This special issue aims to remedy this oversight by illuminating myriad promising trajectories through which scholars in organization studies can return to Freire’s ideas with the intention of enhancing the future of management learning and education

Consistent cosmic shear in the face of systematics: a B-mode analysis of KiDS-450, DES-SV and CFHTLenS

We analyse three public cosmic shear surveys; the Kilo-Degree Survey (KiDS-450), the Dark Energy Survey (DES-SV) and the Canada France Hawaii Telescope Lensing Survey (CFHTLenS). Adopting the “COSEBIs” statistic to cleanly and completely separate the lensing E-modes from the non-lensing B-modes, we detect B-modes in KiDS-450 and CFHTLenS at the level of ∼2.7σ. For DES-SV we detect B-modes at the level of 2.8σ in a non-tomographic analysis, increasing to a 5.5σB-mode detection in a tomographic analysis. In order to understand the origin of these detected B-modes we measure the B-mode signature of a range of different simulated systematics including PSF leakage, random but correlated PSF modelling errors, camera-based additive shear bias and photometric redshift selection bias. We show that any correlation between photometric-noise and the relative orientation of the galaxy to the point-spread-function leads to an ellipticity selection bias in tomographic analyses. This work therefore introduces a new systematic for future lensing surveys to consider. We find that the B-modes in DES-SV appear similar to a superposition of the B-mode signatures from all of the systematics simulated. The KiDS-450 and CFHTLenS B-mode measurements show features that are consistent with a repeating additive shear bias

A developmentally regulated translational control pathway establishes the meiotic chromosome segregation pattern

Production of haploid gametes from diploid progenitor cells is mediated by a specialized cell division, meiosis, where two divisions, meiosis I and II, follow a single S phase. Errors in progression from meiosis I to meiosis II lead to aneuploid and polyploid gametes, but the regulatory mechanisms controlling this transition are poorly understood. Here, we demonstrate that the conserved kinase Ime2 regulates the timing and order of the meiotic divisions by controlling translation. Ime2 coordinates translational activation of a cluster of genes at the meiosis I–meiosis II transition, including the critical determinant of the meiotic chromosome segregation pattern CLB3. We further show that Ime2 mediates translational control through the meiosis-specific RNA-binding protein Rim4. Rim4 inhibits translation of CLB3 during meiosis I by interacting with the 5′ untranslated region (UTR) of CLB3. At the onset of meiosis II, Ime2 kinase activity rises and triggers a decrease in Rim4 protein levels, thereby alleviating translational repression. Our results elucidate a novel developmentally regulated translational control pathway that establishes the meiotic chromosome segregation pattern.American Cancer Society (Post-doctoral Fellowship)Virginia and D.K. Ludwig Fund for Cancer Research (Post-doctoral Fellowship)National Institutes of Health (U.S.) (Grant GM62207

KiDS-i-800: Comparing weak gravitational lensing measurements from same-sky surveys

We present a weak gravitational lensing analysis of 815 deg2 of i-band imaging from the Kilo-Degree Survey (KiDS-i-800). In contrast to the deep r-band observations, which take priority during excellent seeing conditions and form the primary KiDS data set (KiDS-r-450), the complementary yet shallower KiDS-i-800 spans a wide range of observing conditions. The overlapping KiDS-i-800 and KiDS-r-450 imaging therefore provides a unique opportunity to assess the robustness of weak lensing measurements. In our analysis we introduce two new 'null' tests. The 'nulled' two-point shear correlation function uses a matched catalogue to show that the calibrated KiDS-i-800 and KiDS-r-450 shear measurements agree at the level of 1 ± 4 per cent.We use five galaxy lens samples to determine a 'nulled' galaxy-galaxy lensing signal from the full KiDS-i-800 and KiDS-r-450 surveys and find that the measurements agree to 7 ± 5 per cent when the KiDS-i-800 source redshift distribution is calibrated using either spectroscopic redshifts, or the 30-band photometric redshifts from the COSMOS survey

The 2-degree Field Lensing Survey: Photometric redshifts from a large new training sample to r < 19.5

We present a new training set for estimating empirical photometric redshifts of galaxies, which was created as part of the 2-degree Field Lensing Survey project. This training set is located in a ∼700 deg2 area of the Kilo-Degree-Survey South field and is randomly selected and nearly complete at r < 19.5. We investigate the photometric redshift performance obtained with ugriz photometry from VST-ATLAS and W1/W2 from WISE, based on several empirical and template methods. The best redshift errors are obtained with kernel-density estimation (KDE), as are the lowest biases, which are consistent with zero within statistical noise. The 68th percentiles of the redshift scatter for magnitude-limited samples at r < (15.5, 17.5, 19.5) are (0.014, 0.017, 0.028). In this magnitude range, there are no known ambiguities in the colour–redshift map, consistent with a small rate of redshift outliers. In the fainter regime, the KDE method produces p(z) estimates per galaxy that represent unbiased and accurate redshift frequency expectations. The p(z) sum over any subsample is consistent with the true redshift frequency plus Poisson noise. Further improvements in redshift precision at r < 20 would mostly be expected from filter sets with narrower passbands to increase the sensitivity of colours to small changes in redshift.CW was supported by Australian Research Council Laureate Grant FL0992131. Parts of this research were conducted by the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO), through project number CE110001020. MB is supported by the Netherlands Organization for Scientific Research, NWO, through grant number 614.001.451, through FP7 grant number 279396 from the European Research Council and by the Polish National Science Center under contract #UMO-2012/07/D/ST9/02785. CB acknowledges the support of the Australian Research Council through the award of a Future Fellowship. CH acknowledges support from the European Research Council under grant number 647112. HH was supported by the Deutsche Forschungsgemeinschaft under Emmy Noether grant Hi 1495/2-1. TE and DK are supported by the Deutsche Forschungsgemeinschaft in the framework of the TR33 ‘The Dark Universe’. This study is based in part on data acquired at the Australian Astronomical Observatory, through program A/2014B/08. KK acknowledges support by the Alexander von Humboldt Foundation. DP is supported by the Australian Research Council Future Fellowship Grant FT13010108

Testing gravity using galaxy-galaxy lensing and clustering amplitudes in KiDS-1000, BOSS, and 2dFLenS

The physics of gravity on cosmological scales affects both the rate of assembly of large-scale structure and the gravitational lensing ofbackground light through this cosmic web. By comparing the amplitude of these different observational signatures, we can constructtests that can distinguish general relativity from its potential modifications. We used the latest weak gravitational lensing dataset fromthe Kilo-Degree Survey, KiDS-1000, in conjunction with overlapping galaxy spectroscopic redshift surveys, BOSS and 2dFLenS, toperform the most precise existing amplitude-ratio test. We measured the associatedEGstatistic with 15−20% errors in five∆z=0.1tomographic redshift bins in the range 0.2<z<0.7 on projected scales up to 100h−1Mpc. The scale-independence and redshift-dependence of these measurements are consistent with the theoretical expectation of general relativity in a Universe with matterdensityΩm=0.27 +- 0.04. We demonstrate that our results are robust against different analysis choices, including schemes forcorrecting the effects of source photometric redshift errors, and we compare the performance of angular and projected galaxy-galaxylensing statistics.the European Research Council under grant numbers 647112 (MA, BG, CH, TT), 770935 (AD, HH, JLvdB, AHW) and 693024 (SJ); the Polish Ministry of Science and Higher Education through grant DIR/WK/2018/12 and the Polish National Science Center through grant 2018/30/E/ST9/00698 (MB); the Max Planck Society and the Alexander von Humboldt Foundation in the framework of the Max Planck-Humboldt Research Award endowed by the Federal Ministry of Education and Research (CH); Heisenberg grant Hi 1495/5-1 of the Deutsche Forschungsgemeinschaft (HH); the Beecroft Trust (SJ); Vici grant 639.043.512 financed by the Netherlands Organisation for Scientific Research (AK); the Alexander von Humboldt Foundation (KK); the NSFC of China grant 11973070, the Shanghai Committee of Science and Technology grant 19ZR1466600 and Key Research Program of Frontier Sciences grant ZDBS-LY-7013 (HYS); and the European Union’s Horizon 2020 research and innovation programme under the Marie SklodowskaCurie grant 797794 (TT)

2dFLenS and KiDS: determining source redshift distributions with cross-correlations

We develop a statistical estimator to infer the redshift probability distribution of a photometric sample of galaxies from its angular cross-correlation in redshift bins with an overlapping spectroscopic sample. This estimator is a minimum-variance weighted quadratic function of the data: a quadratic estimator. This extends and modifies the methodology presented by McQuinn & White. The derived source redshift distribution is degenerate with the source galaxy bias, which must be constrained via additional assumptions. We apply this estimator to constrain source galaxy redshift distributions in the Kilo-Degree imaging survey through cross-correlation with the spectroscopic 2-degree Field Lensing Survey, presenting results first as a binned step-wise distribution in the range z < 0.8, and then building a continuous distribution using a Gaussian process model. We demonstrate the robustness of our methodology using mock catalogues constructed from N-body simulations, and comparisons with other techniques for inferring the redshift distribution

KiDS+2dFLenS+GAMA: Testing the cosmological model with the EG statistic

We present a new measurement of EG, which combines measurements of weak gravitational lensing, galaxy clustering, and redshift-space distortions. This statistic was proposed as a consistency test of General Relativity (GR) that is insensitive to linear, deterministic galaxy bias, and the matter clustering amplitude. We combine deep imaging data from KiDS with overlapping spectroscopy from 2dFLenS, BOSS DR12, and GAMA and find EG (z=0.267) = 0.43 ± 0.13(GAMA), EG (z=0.305) = 0.27 ± 0.08 (LOWZ+2dFLOZ), and EG (z=0.0554) = 0.26 ± 0.07 (CMASS + 2dFHIZ). We demonstrate that the existing tension in the value of the matter density parameter hinders the robustness of this statistic as solely a test of GR. We find that our EG measurements, as well as existing ones in the literature, favour a lower matter density cosmology than the cosmic microwave background. For a flat ΔCDM Universe, we find Ωm(z = 0) = 0.25 ± 0.03. With this paper, we publicly release the 2dFLenS data set at: http://2dflens.swin.edu.au.AA, CH, MA, and SJ acknowledge support from the European Research Council under grant numbers 647112 (CH and MA) and 693024 (SJ). CB acknowledges the support of the Australian Research Council through the award of a Future Fellowship. DL acknowledges support from the McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University. HHi acknowledges support from an Emmy Noether grant (No. Hi 1495/2-1) of the Deutsche Forschungsgemeinschaft. HHo acknowledges support from Vici grant 639.043.512, financed by the Netherlands Organisation for Scientific Research (NWO). BJ acknowledges support by an STFC Ernest Rutherford Fellowship, grant reference ST/J004421/1. JHD acknowledges support from the EuropeansCommission under a Marie-Sklodwoska-Curie European Fellowship (EU project 656869). SJ also acknowledges support from the Beecroft Trust. DP acknowledges the support of the Australian Research Council through the award of a Future Fellowship. MB is supported by the Netherlands Organisation for Scientific Research, NWO, through grant number 614.001.45