Abstract
It is well known that the probability distribution function (PDF) of galaxy density contrast is approximately lognormal; whether the PDF of mass fluctuations derived from weak lensing convergence (κWL) is lognormal is less well established. We derive PDFs of the galaxy and projected matter density distributions via the counts-in-cells (CiC) method. We use maps of galaxies and weak lensing convergence produced from the Dark Energy Survey Science Verification data over 139 deg2. We test whether the underlying density contrast is well described by a lognormal distribution for the galaxies, the convergence and their joint PDF. We confirm that the galaxy density contrast distribution is well modelled by a lognormal PDF convolved with Poisson noise at angular scales from 10 to 40 arcmin (corresponding to physical scales of 3-10 Mpc). We note that as κWL is a weighted sum of the mass fluctuations along the line of sight, its PDF is expected to be only approximately lognormal. We find that the κWL distribution is well modelled by a lognormal PDF convolved with Gaussian shape noise at scales between 10 and 20 arcmin, with a best-fitting χ2/dof of 1.11 compared to 1.84 for a Gaussian model, corresponding to p-values 0.35 and 0.07, respectively, at a scale of 10 arcmin. Above 20 arcmin a simple Gaussian model is sufficient. The joint PDF is also reasonably fitted by a bivariate lognormal. As a consistency check, we compare the variances derived from the lognormal modelling with those directly measured via CiC. Our methods are validated against maps from the MICE Grand Challenge N-body simulation.
Original language | English |
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Pages (from-to) | 1444-1461 |
Number of pages | 18 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 466 |
Issue number | 2 |
DOIs | |
State | Published - Apr 1 2017 |
Externally published | Yes |
Funding
The MICE simulations have been developed at the MareNos-trum supercomputer (BSC-CNS) thanks to grants AECT-2006-2-0011 through AECT-2015-1-0013. Data products have been stored at the Port d’Informació Científica (PIC), and distributed through the CosmoHub webportal (cosmohub.pic.es). Funding for this project was partially provided by the Spanish Minis-terio de Ciencia e Innovacion (MICINN), projects 200850I176, AYA2009-13936, AYA2012-39620, AYA2013-44327, ESP2013-48274, ESP2014-58384, Consolider-Ingenio CSD2007-00060, research project 2009-SGR-1398 from Generalitat de Catalunya, and the Ramon y Cajal MICINN programme. This paper has gone through internal review by the DES collaboration. LC thanks the Perren Fund for a studentship. OL, DK and MM acknowledge support from a European Research Council Advanced Grant FP7/291329. Funding for the DES Projects has been provided by the US Department of Energy, the US National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, the Center for Cosmology and Astro-Particle Physics at the Ohio State University, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundac¸ão Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desen-volvimento Científico e Tecnológico and the Ministério da Ciência, Tecnologia e Inovac¸ão, the Deutsche Forschungsgemeinschaft and the Collaborating Institutions in the Dark Energy Survey. We would like to thank Ludovic Van Waerbeke for extremely useful exchanges on the formalism for the calculation of the convergence second moment. We thank the anonymous referee for suggesting that the skewness of the convergence PDF can be used to estimate the amplitude of fluctuations, ?8, as presented in Section 6.1. The MICE simulations have been developed at the MareNostrum supercomputer (BSC-CNS) thanks to grants AECT-2006-2-0011 through AECT-2015-1-0013. Data products have been stored at the Port d'Informaci? Cient?fica (PIC), and distributed through the CosmoHub webportal (cosmohub.pic.es). Funding for this project was partially provided by the Spanish Ministerio de Ciencia e Innovacion (MICINN), projects 200850I176, AYA2009-13936, AYA2012-39620, AYA2013-44327, ESP2013-48274, ESP2014-58384, Consolider-Ingenio CSD2007-00060, research project 2009-SGR-1398 from Generalitat de Catalunya, and the Ramon y Cajal MICINN programme. We are grateful for the extraordinary contributions of our CTIO colleagues and the DECam Construction, Commissioning and Science Verification teams in achieving the excellent instrument and telescope conditions that have made this work possible. The success of this project also relies critically on the expertise and dedication of the DES Data Management group. Funding for the DES Projects has been provided by the US Department of Energy, the US National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, the Center for Cosmology and Astro-Particle Physics at the Ohio State University, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico and the Minist?rio da Ci?ncia, Tecnologia e Inova??o, the Deutsche Forschungsgemeinschaft and the Collaborating Institutions in the Dark Energy Survey. The Collaborating Institutions are Argonne National Laboratory, the University of California at Santa Cruz, the University of Cambridge, Centro de Investigaciones Energ?ticas, Medioambientales y Tecnol?gicas-Madrid, the University of Chicago, University College London, the DES-Brazil Consortium, the University of Edinburgh, the Eidgen?ssische Technische Hochschule (ETH) Z?rich, Fermi National Accelerator Laboratory, the University of Illinois at Urbana-Champaign, the Institut de Ci?ncies de l'Espai (IEEC/CSIC), the Institut de F?sica d'Altes Energies, Lawrence Berkeley National Laboratory, the Ludwig-Maximilians Universit?t M?nchen and the associated Excellence Cluster Universe, the University of Michigan, the National Optical Astronomy Observatory, the University of Nottingham, the Ohio State University, the University of Pennsylvania, the University of Portsmouth, SLAC National Accelerator Laboratory, Stanford University, the University of Sussex, Texas A&M University and the OzDES Membership Consortium. The DES data management system is supported by the National Science Foundation under Grant Number AST-1138766. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2012-39559, ESP2013-48274, FPA2013-47986, and Centro de Excelencia Severo Ochoa SEV-2012-0234. Research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) including ERC grant agreements 240672, 291329 and 306478. This paper has gone through internal review by the DES collaboration. LC thanks the Perren Fund for a studentship. OL, DK and MM acknowledge support from a European Research Council Advanced Grant FP7/291329. The DES data management system is supported by the National Science Foundation under Grant Number AST-1138766. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2012-39559, ESP2013-48274, FPA2013-47986, and Centro de Excelencia Severo Ochoa SEV-2012-0234. Research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) including ERC grant agreements 240672, 291329 and 306478.
Funders | Funder number |
---|---|
Centro de Excelencia Severo Ochoa | SEV-2012-0234 |
Collaborating Institutions are Argonne National Laboratory | |
Collaborating Institutions in the Dark Energy Survey | |
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico | |
FP7/2007 | |
Institut de Ci?ncies de l'Espai | |
Institut de F?sica d'Altes Energies | |
Kavli Institute of Cosmological Physics at the University of Chicago | |
Ludwig-Maximilians Universit?t M?nchen | |
Minist?rio da Ci?ncia | |
Ministry of Science and Education of Spain | |
Ministério da Ciência | |
Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University | |
National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign | |
Perren Fund | |
Science and Technology Facilities Council of the United Kingdom | |
Spanish Minis-terio de Ciencia e Innovacion | |
Spanish Ministerio de Ciencia e Innovacion | |
US Department of Energy | |
US National Science Foundation | |
National Science Foundation | AST-1138766 |
U.S. Department of Energy | |
University of Illinois at Urbana-Champaign | |
Stanford University | |
Lawrence Berkeley National Laboratory | |
University of California, Santa Cruz | |
University of Pennsylvania | |
Ohio State University | |
University of Chicago | |
University of Michigan | |
Texas A and M University | |
University of Portsmouth | |
National Centre for Supercomputing Applications | |
Seventh Framework Programme | 1138766, 240672, 306478, 291329 |
SLAC National Accelerator Laboratory | |
Higher Education Funding Council for England | |
Center for Cosmology and Astroparticle Physics, Ohio State University | |
Science and Technology Facilities Council | |
University College London | |
European Research Council | FP7/291329 |
University of Nottingham | |
University of Sussex | |
University of Edinburgh | |
Deutsche Forschungsgemeinschaft | |
Generalitat de Catalunya | |
Eidgenössische Technische Hochschule Zürich | |
Ministerio de Economía y Competitividad | FPA2013-47986, AYA2012-39559, ESP2013-48274 |
Conselho Nacional de Desenvolvimento Científico e Tecnológico | |
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro | |
Financiadora de Estudos e Projetos | |
Ministerio de Ciencia e Innovación | 200850I176, 2009-SGR-1398, AYA2012-39620, CSD2007-00060, AYA2009-13936, AYA2013-44327, ESP2014-58384 |
Seventh Framework Programme | |
Universidade do Estado do Rio de Janeiro | |
Ministry of Education and Science of Ukraine |
Keywords
- Cosmology: observations
- Gravitational lensing: weak
- Large-scale structure of Universe