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Related papers: Numerical complexity of the joint nulled weak-lens…

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In tomographic weak lensing surveys, the presence of nulling properties reveals symmetries inherent in the data, which rely solely on the geometrical properties of the Universe. Ensuring its validity thus provides us with constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-05 David Touzeau , Francis Bernardeau , Karim Benabed , Sandrine Codis

We present an analysis comparing nulling strategies for reducing the impact of baryon feedback on cosmic shear measurements. We consider three different approaches which aim to `null' the high-$k$ modes using transformations applied to the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-06 Naomi Clare Robertson , Alex Hall

Weak gravitational lensing surveys have the potential to directly probe mass density fluctuation in the universe. Recent studies have shown that it is possible to model the statistics of the convergence field at small angular scales by…

Astrophysics · Physics 2008-11-26 Dipak Munshi , Bhuvnesh Jain

We examine the cosmological information available from the 1-point probability distribution (PDF) of the weak-lensing convergence field, utilizing fast L-PICOLA simulations and a Fisher analysis. We find competitive constraints in the…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Kenneth Patton , Jonathan Blazek , Klaus Honscheid , Eric Huff , Peter Melchior , Ashley J. Ross , Eric Suchyta

With the availability of thousands of type Ia supernovae in the near future the magnitude scatter induced by lensing will become a major issue as it affects parameter estimation. Current N-body simulations are too time consuming to be…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-10 Valerio Marra , Miguel Quartin , Luca Amendola

Weak gravitational lensing is a powerful probe of the large-scale cosmic matter distribution. Wide-field galaxy surveys allow us to generate the so-called weak lensing maps, but actual observations suffer from noise due to imperfect…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-21 Masato Shirasaki , Naoki Yoshida , Shiro Ikeda

The current methods available to estimate gravitational shear from astronomical images of galaxies introduce systematic errors which can affect the accuracy of weak lensing cosmological constraints. We study the impact of KSB shape…

Weak lensing surveys, along with most other late-Universe probes, have consistently measured a lower amplitude of the matter fluctuation spectrum, denoted by the parameter $S_8$, compared to predictions from early-Universe measurements in…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-25 Shiming Gu , Ludovic van Waerbeke , Francis Bernardeau , Roohi Dalal

Weak gravitational lensing is a powerful probe of the universe's growth history. While traditional two-point statistics capture only the Gaussian features of the convergence field, deep learning methods such as convolutional neural networks…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-09 Jash Kakadia , Shubh Agrawal , Kunhao Zhong , Bhuvnesh Jain

Upcoming weak lensing surveys on wide fields will provide the opportunity to reconstruct the structure along the line of sight tomographically by employing photometric redshift information about the source distribution. We define…

Astrophysics · Physics 2009-10-31 Wayne Hu

We quantify the cosmological constraining power of the `lensing PDF' - the one-point probability density of weak lensing convergence maps - by modelling this statistic numerically with an emulator trained on $w$CDM cosmic shear simulations.…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Benjamin Giblin , Yan-Chuan Cai , Joachim Harnois-Déraps

Here we present a number of improvements to weak lensing 3D power spectrum analysis, 3D cosmic shear, that uses the shape and redshift information of every galaxy to constrain cosmological parameters. We show how photometric redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 T. D. Kitching , A. F. Heavens , L. Miller

We address key points for an efficient implementation of likelihood codes for modern weak lensing large-scale structure surveys. Specifically, we focus on the joint weak lensing convergence power spectrum-bispectrum probe and we tackle the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-02 Matteo Rizzato , Karim Benabed , Francis Bernardeau , Fabien Lacasa

We present the results of weak gravitational lensing statistics in four different cosmological $N$-body simulations. The data has been generated using an algorithm for the three-dimensional shear, which makes use of a variable softening…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman , C. J. Fluke

The one-point probability distribution function (pdf) of the large-scale density field is an important tool to follow the evolution of cosmological structures. In this paper we present a new model for this pdf for all regimes and all…

Astrophysics · Physics 2009-11-10 Patrick Valageas , Dipak Munshi

Weak lensing of galaxies and CMB photons through the large-scale structure of the Universe is one of the most promising cosmological probes with upcoming experiments dedicated to its measurements such as Euclid/LSST and CMB Stage 4…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Alexandre Barthelemy , Sandrine Codis , Francis Bernardeau

Weak lensing provides a direct way of mapping the density distribution in the universe. To reconstruct the density field from the shear catalog, an important step is to build the shear field from the shear catalog, which can be quite…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-27 Haoran Wang , Jun Zhang , Hekun Li , Cong Liu

The subject of this paper is optimisation of weak lensing tomography: We carry out numerical minimisation of a measure of total statistical error as a function of the redshifts of the tomographic bin edges by means of a Nelder-Mead…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-21 Marvin Sipp , Bjoern Malte Schaefer , Robert Reischke

Galaxy photometric redshift (photo-$z$) is crucial in cosmological studies, such as weak gravitational lensing and galaxy angular clustering measurements. In this work, we try to extract photo-$z$ information and construct its probability…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-16 Xingchen Zhou , Yan Gong , Xian-Min Meng , Xuelei Chen , Zhu Chen , Wei Du , Liping Fu , Zhijian Luo

We explore the enhanced self-calibration of photometric galaxy redshift distributions, $n(z)$, through the combination of up to six two-point functions. Our $\rm 3\times2pt$ configuration is comprised of photometric shear, spectroscopic…