English
Related papers

Related papers: A New Algorithm for Computing Statistics of Weak L…

200 papers

Weak gravitational lensing has the potential to constrain cosmological parameters to high precision. However, as shown by the Shear TEsting Programmes (STEP) and GRavitational lEnsing Accuracy Testing (GREAT) Challenges, measuring galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Tomasz Kacprzak , Joe Zuntz , Barnaby Rowe , Sarah Bridle , Alexandre Refregier , Adam Amara , Lisa Voigt , Michael Hirsch

The halo model (HM) describes the inhomogeneous universe as a collection of halos. The full nonlinear power spectrum of the universe is well approximated by the HM, whose prediction can be easily computed without lengthy numerical…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-07 Kimmo Kainulainen , Valerio Marra

The weak distortions produced by gravitational lensing in the images of background galaxies provide a method to measure directly the distribution of mass in the universe. However this technique requires high precision measurements of the…

Astrophysics · Physics 2009-10-31 Jason Rhodes , Alexandre Refregier , Ed Groth

Diffusion kurtosis imaging is an extension of diffusion tensor imaging that provides scientifically and clinically valuable information about brain tissue microstructure but suffers from poor robustness to noise, especially in voxels…

Strong lensing is a sensitive probe of the small-scale density fluctuations in the Universe. We implement a novel approach to modeling strongly lensed systems using probabilistic cataloging, which is a transdimensional, hierarchical, and…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-06 Tansu Daylan , Francis-Yan Cyr-Racine , Ana Diaz Rivero , Cora Dvorkin , Douglas P. Finkbeiner

While the direct detection of the dark-matter particle remains very challenging, the nature of dark matter could be possibly constrained by comparing the observed abundance and properties of small-scale sub-galactic mass structures with…

Astrophysics of Galaxies · Physics 2023-05-17 D. Bayer , L. V. E. Koopmans , J. P. McKean , S. Vegetti , T. Treu , C. D. Fassnacht , K. Glazebrook

We present the theoretical and analytical bases of optimal techniques to measure weak gravitational shear from images of galaxies. We first characterize the geometric space of shears and ellipticity, then use this geometric interpretation…

Astrophysics · Physics 2009-11-06 G. M. Bernstein , M. Jarvis

We present a new approach to measure the mass function of dark matter halos and to discriminate models with differing values of Omega through weak gravitational lensing. We measure the distribution of peaks from simulated lensing surveys…

Astrophysics · Physics 2009-10-31 Bhuvnesh Jain , Ludovic Van Waerbeke

Upcoming deep optical surveys, such as the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), will scan the sky to unprecedented depths, detecting billions of galaxies. However, this amount of detections will lead to the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-04 Manon Ramel , Cyrille Doux , Marine Kuna

I present a new algorithm, CALCLENS, for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-15 Matthew R. Becker

In this article we present an analytic calculation of the probability distribution of the magnification of distant sources due to weak gravitational lensing from non-linear scales. We use a realistic description of the non-linear density…

Astrophysics · Physics 2011-05-23 P. Valageas

The Dark Matter present in the Large-Scale Structure of the Universe is invisible, but its presence can be inferred through the small gravitational lensing effect it has on the images of far away galaxies. By measuring this lensing effect…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Benjamin Remy , Francois Lanusse , Zaccharie Ramzi , Jia Liu , Niall Jeffrey , Jean-Luc Starck

The unprecedented amount and the excellent quality of lensing data that the upcoming ground- and space-based surveys will produce represent a great opportunity to shed light on the questions that still remain unanswered concerning our…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Carolina Parroni , Edouard Tollet , Vincenzo F. Cardone , Roberto Maoli , Roberto Scaramella

We study the bias and scatter in mass measurements of galaxy clusters resulting from fitting a spherically-symmetric Navarro, Frenk & White model to the reduced tangential shear profile measured in weak lensing observations. The reduced…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-23 Matthew R. Becker , Andrey V. Kravtsov

Strong-lensing images provide a wealth of information both about the magnified source and about the dark matter distribution in the lens. Precision analyses of these images can be used to constrain the nature of dark matter. However, this…

Instrumentation and Methods for Astrophysics · Physics 2022-05-25 Konstantin Karchev , Adam Coogan , Christoph Weniger

Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or…

Observations of the large-scale structure (LSS) implicitly assume an ideal FLRW observer with the ambient structure having no influence on the observer. However, due to correlations in the LSS, cosmological observables are dependent on the…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-05 Robert Reischke , Björn malte Schäfer , Krzysztof Bolejko , Geraint F. Lewis , Max Lautsch

We present a novel approach for reconstructing the projected mass distribution of clusters of galaxies from sparse and noisy weak gravitational lensing shear data. The reconstructions are regularised using knowledge gained from numerical…

Astrophysics · Physics 2009-11-24 Phil Marshall

We present a simple method to accurately infer line of sight (LOS) integrated lensing effects for galaxy scale strong lens systems through image reconstruction. Our approach enables us to separate weak lensing LOS effects from the main…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-02 Simon Birrer , Cyril Welschen , Adam Amara , Alexandre Refregier

We study the domain of validity of Perturbation Theory (PT), by comparing its predictions for the reduced skewness, s_3, and kurtosis, s_4, of the projected cosmological density field, with the results of N-body simulations. We investigate…

Astrophysics · Physics 2011-05-23 E. Gaztanaga , F. Bernardeau