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Deep learning is a powerful analysis technique that has recently been proposed as a method to constrain cosmological parameters from weak lensing mass maps. Due to its ability to learn relevant features from the data, it is able to extract…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-26 Janis Fluri , Tomasz Kacprzak , Aurelien Lucchi , Alexandre Refregier , Adam Amara , Thomas Hofmann

We study robust regression under a contamination model in which covariates are clean while the responses may be corrupted in an adaptive manner. Unlike the classical Huber's contamination model, where both covariates and responses may be…

Statistics Theory · Mathematics 2026-04-07 Ilias Diakonikolas , Chao Gao , Daniel M. Kane , Ankit Pensia , Dong Xie

We study the statistics of weak lensing convergence peaks, such as their abundance and two-point correlation function (2PCF), for a wide range of cosmological parameters $\Omega_m$ and $\sigma_8$ within the standard $\Lambda$CDM paradigm,…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-08 Christopher T. Davies , Marius Cautun , Baojiu Li

We perform a cosmic shear analysis of the COMBO-17 survey -- a unique dataset with shear quality R-band imaging and accurate photometric redshift estimates (dz=0.05) for ~90% of galaxies to R=24.0. We undertake a full maximum likelihood…

Astrophysics · Physics 2008-11-26 M. L. Brown , A. N. Taylor , D. J. Bacon , M. E. Gray , S. Dye , K. Meisenheimer , C. Wolf

Deep convolutional neural networks (CNN) has become the most promising method for object recognition, repeatedly demonstrating record breaking results for image classification and object detection in recent years. However, a very deep CNN…

Computer Vision and Pattern Recognition · Computer Science 2014-12-22 Yunchao Gong , Liu Liu , Ming Yang , Lubomir Bourdev

We present estimates of the gravitational lensing shear variance obtained from images taken at the CFHT using the UH8K CCD mosaic camera. Six fields were observed for a total of 1 hour each in V and I, resulting in catalogs containing…

Astrophysics · Physics 2007-05-23 Nick Kaiser , Gillian Wilson , Gerard A. Luppino

Large data-sets defined on the sphere arise in many fields. In particular, recent and forthcoming observations of the anisotropies of the cosmic microwave background (CMB) made on the celestial sphere contain approximately three and fifty…

Instrumentation and Methods for Astrophysics · Physics 2011-08-22 J. D. McEwen , Y. Wiaux , D. M. Eyers

We used the mark weighted correlation functions (MCFs), $W(s)$, to study the large scale structure of the Universe. We studied five types of MCFs with the weighting scheme $\rho^\alpha$, where $\rho$ is the local density, and $\alpha$ is…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-02 Yizhao Yang , Haitao Miao , Qinglin Ma , Miaoxin Liu , Cristiano G. Sabiu , Jaime Forero-Romero , Yuanzhu Huang , Limin Lai , Qiyue Qian , Yi Zheng , Xiao-Dong Li

Multivariate mutual information provides a conceptual framework for characterizing higher-order interactions in complex systems. Two well-known measures of multivariate information---total correlation and dual total correlation---admit a…

Information Theory · Computer Science 2018-11-28 Kyle Reing , Greg Ver Steeg , Aram Galstyan

On-going measurements of the cosmic radiation (nuclear, electronic, and gamma-ray) are shedding new light on cosmic-ray physics. A comprehensive picture of these data relies on an accurate determination of the transport and source…

High Energy Astrophysical Phenomena · Physics 2010-07-08 A. Putze , L. Derome , D. Maurin

We present simulations of a cosmic shear survey and show how the survey geometry influences the accuracy of determination of cosmological parameters. We numerically calculate the full covariance matrices of the two-point statistics \xi_+,…

Astrophysics · Physics 2007-05-23 Martin Kilbinger

We explore and compare the performances of two nonlinear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-LCDM cosmologies. The…

Astrophysics · Physics 2008-11-26 Jan Hamann , Steen Hannestad , Alessandro Melchiorri , Yvonne Y. Y. Wong

In pulsar astronomy, detecting effective pulsar signals among numerous pulsar candidates is an important research topic. Starting from space X-ray pulsar signals, the two-dimensional autocorrelation profile map (2D-APM) feature modelling…

Instrumentation and Methods for Astrophysics · Physics 2021-09-08 Longqi Wang , Jing Jin , Lu Liu , Yi Shen

We carry out a direct comparison of experimental and numerical realizations of the exact same granular system as it undergoes shear jamming. We adjust the numerical methods used to optimally represent the experimental settings and outcomes…

Cosmological weak lensing gives rise to correlations in the ellipticities of faint galaxies. This cosmic shear signal depends upon the matter power spectrum, thus providing a means to constrain cosmological parameters. It has recently been…

Astrophysics · Physics 2009-11-07 Lindsay King , Peter Schneider

We analyze the quasar two-point correlation function (2pCF) within the redshift interval $0.8<z<2.2$ using a sample of 52303 quasars selected from the recent 7th Data Release of the Sloan Digital Sky Survey. Our approach to 2pCF uses a…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-12 G. Ivashchenko , V. I. Zhdanov , A. V. Tugay

High-dimensional, large-sample astrophysical databases of galaxy clusters, such as the Chandra Deep Field South COMBO-17 database, provide measurements on many variables for thousands of galaxies and a range of redshifts. Current…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Elizabeth Martinez-Gomez , Mercedes T. Richards , Donald St. P. Richards

Interferometers with single particles are susceptible for dephasing perturbations from the environment, such as electromagnetic oscillations or mechanical vibrations. On the one hand, this limits sensitive quantum phase measurements as it…

We undertake the first comprehensive and quantitative real-space analysis of the cosmological information content in the environments of the cosmic web (voids, filaments, walls, and nodes) up to non-linear scales, $k = 0.5$ $h$/Mpc. Relying…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-25 Tony Bonnaire , Nabila Aghanim , Joseph Kuruvilla , Aurélien Decelle