English
Related papers

Related papers: AKRA 2.0: Accurate Kappa Reconstruction Algorithm …

200 papers

Weak gravitational lensing is an invaluable tool for understanding fundamental cosmological physics. An unresolved issue in weak lensing cosmology is to accurately reconstruct the lensing convergence $\kappa$ maps from discrete shear…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 Yuan Shi , Pengjie Zhang , Zeyang Sun , Yihe Wang

Weak lensing mass-mapping from shear catalogs faces systematic challenges from survey masks and spatially varying noise. To overcome these issues and reconstruct unbiased convergence $\kappa$ maps, we have constructed the AKRA (Accurate…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Yuan Shi , Pengjie Zhang , Zhao Chen , Jian Qin , Li Cui , Furen Deng , Ji Yao

We present KaRMMa 2.0, an updated version of the mass map reconstruction code introduced in Fiedorowicz et al. (2022). KaRMMa is a full-sky Bayesian algorithm for reconstructing weak lensing mass maps from shear data. It forward-models the…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-25 Pier Fiedorowicz , Eduardo Rozo , Supranta S. Boruah

We present KaRMMa, a novel method for performing mass map reconstruction from weak-lensing surveys. We employ a fully Bayesian approach with a physically motivated lognormal prior to sample from the posterior distribution of convergence…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-02 Pier Fiedorowicz , Eduardo Rozo , Supranta S. Boruah , Chihway Chang , Marco Gatti

We present a novel method for reconstructing weak lensing mass or convergence maps as a probe to study non-Gaussianities in the cosmic density field. While previous surveys have relied on a flat-sky approximation, the forthcoming stage IV…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-03 Vanshika Kansal

We present a numerical investigation of nonlinear cluster lens reconstruction using weak lensing mass mapping. Recent advances in imaging and shear estimation have pushed reliable reduced shear measurements closer to cluster cores, making…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Yuan Shi , Li Cui

Convergence maps of the integrated matter distribution are a key science result from weak gravitational lensing surveys. To date, recovering convergence maps has been performed using a planar approximation of the celestial sphere. However,…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-16 Christopher G. R. Wallis , Matthew A. Price , Jason D. McEwen , Thomas D. Kitching , Boris Leistedt , Antoine Plouviez

Within the context of upcoming full-sky lensing surveys, the edge-preserving non- linear algorithm Aski is presented. Using the framework of Maximum A Posteriori inversion, it aims at recovering the full-sky convergence map from surveys…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. Pichon , E. Thiebaut , S. Prunet , K. Benabed , S. Colombi , T. Sousbie , R. Teyssier

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

Purpose: To develop a scan-specific model that estimates and corrects k-space errors made when reconstructing accelerated Magnetic Resonance Imaging (MRI) data. Methods: Scan-Specific Artifact Reduction in k-space (SPARK) trains a…

Signal Processing · Electrical Eng. & Systems 2022-04-29 Yamin Arefeen , Onur Beker , Jaejin Cho , Heng Yu , Elfar Adalsteinsson , Berkin Bilgic

Weak lensing observations measure the shear field and hence the gradient of the dimensionless surface density $\kappa$. We present several new algorithms to recover $\kappa$ {}from shear estimates on a finite region and compare how they…

Astrophysics · Physics 2009-10-28 Gordon Squires , Nick Kaiser

Most cosmic shear analyses to date have relied on summary statistics (e.g. $\xi_+$ and $\xi_-$). These types of analyses are necessarily sub-optimal, as the use of summary statistics is lossy. In this paper, we forward-model the convergence…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-29 Supranta Sarma Boruah , Eduardo Rozo , Pier Fiedorowicz

As Part I of a paper series showcasing a new imaging framework, we consider the recently proposed unconstrained Sparsity Averaging Reweighted Analysis (uSARA) optimisation algorithm for wide-field, high-resolution, high-dynamic range,…

Instrumentation and Methods for Astrophysics · Physics 2023-09-11 Amanda G. Wilber , Arwa Dabbech , Adrian Jackson , Yves Wiaux

Integral field spectroscopy can map astronomical objects spatially and spectroscopically. Due to instrumental and atmospheric effects, it is common for integral field instruments to yield a sampling of the sky image that is both irregular…

Astrophysics of Galaxies · Physics 2020-01-08 Dou Liu , Michael R. Blanton , David R. Law

High precision cosmological distance measurements towards individual objects such as time delay gravitational lenses or type Ia supernovae are affected by weak lensing perturbations by galaxies and groups along the line of sight. In time…

Accurate estimation of the covariance matrix of cosmic shear statistics is essential for cosmological analyses using current and upcoming wide-area weak lensing surveys. In this work, we investigate analytical methods for computing the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-18 Kosuke Nagura , Ryo Terasawa , Taisei Terawaki , Masahiro Takada

Weak lensing, which is the deflection of light by matter along the line of sight, has proven to be an efficient method for constraining models of structure formation and reveal the nature of dark energy. So far, most weak-lensing studies…

In \citep{Qin+}, we attempted to reconstruct the weak lensing convergence map $\hat{\kappa}$ from cosmic magnification by linearly weighting the DECaLS galaxy overdensities in different magnitude bins of $grz$ photometry bands. The…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-03 Jian Qin , Pengjie Zhang , Yu Yu , Haojie Xu , Ji Yao , Yuan Shi , Huanyuan Shan

Current and upcoming wide-field, ground-based, broad-band imaging surveys promise to address a wide range of outstanding problems in galaxy formation and cosmology. Several such uses of ground-based data, especially weak gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Rachel Mandelbaum , Christopher M. Hirata , Alexie Leauthaud , Richard J. Massey , Jason Rhodes

We apply a mass reconstruction technique to simulated large-scale structure gravitational distortion maps, from 2.5' to 10 degree scales, for different cosmological scenarii. The projected mass is reconstructed using a non-parametric least…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke , F. Bernardeau , Y. Mellier
‹ Prev 1 2 3 10 Next ›