English
Related papers

Related papers: Comparing approximate methods for mock catalogues …

200 papers

Physics-based covariance models provide a systematic way to construct covariance models that are consistent with the underlying physical laws in Gaussian process analysis. The unknown parameters in the covariance models can be estimated…

Computation · Statistics 2023-03-20 Yian Chen , Mihai Anitescu

Analysis of large galaxy surveys requires confidence in the robustness of numerical simulation methods. The simulations are used to construct mock galaxy catalogs to validate data analysis pipelines and identify potential systematics. We…

We propose to use a simple observable, the fractional area of "hot spots" in weak gravitational lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-convergence…

Astrophysics · Physics 2011-02-11 Sheng Wang , Zoltán Haiman , Morgan May

We describe the construction of an N-body simulation that mimics the true velocity and mass-density fields in a box of side 256\hmpc about the Local Group , and the production of mock catalogs that mimic in detail current catalogs of…

Astrophysics · Physics 2009-10-28 Tsafrir Kolatt , Avishai Dekel , Galit Ganon , Jeffrey Willick

We present a perturbative treatment of nonlinear galaxy clustering in the context of the cubic Galileon modified gravity model, in terms of 2nd order Lagrangian Perturbation theory and an extension of ellipsoidal collapse that includes…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-14 Yanling Song , Chiara Moretti , Pierluigi Monaco , Bin Hu

We introduce a novel technique for constraining cosmological parameters and galaxy assembly bias using non-linear redshift-space clustering of galaxies. We scale cosmological N-body simulations and insert galaxies with the SubHalo Abundance…

This paper is the first in a series in which we perform an extensive comparison of various galaxy-based cluster mass estimation techniques that utilise the positions, velocities and colours of galaxies. Our primary aim is to test the…

We present a method for modelling the cluster-galaxy correlation function in redshift-space, down to ~ Mpc scales. The method builds upon the so-called Galaxy Infall Kinematics (GIK) model, a parametric model for the pairwise velocities of…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-04 Andrew Robertson , Eric Huff , Katarina Markovic , Baojiu Li

The use of sparse precision (inverse covariance) matrices has become popular because they allow for efficient algorithms for joint inference in high-dimensional models. Many applications require the computation of certain elements of the…

Computation · Statistics 2017-12-06 Per Sidén , Finn Lindgren , David Bolin , Mattias Villani

We describe the construction of a suite of galaxy cluster mock catalogues from N-body simulations, based on the properties of the new ROSAT-ESO Flux-Limited X-Ray (REFLEX II) galaxy cluster catalogue. Our procedure is based on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 A. Balaguera-Antolínez , A. G. Sánchez , H. Böhringer , C. Collins

We present a new method of constraining the mass and velocity anisotropy profiles of galaxy clusters from kinematic data. The method is based on a model of the phase space density which allows the anisotropy to vary with radius between two…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Radoslaw Wojtak , Ewa L. Lokas , Gary A. Mamon , Stefan Gottloeber

Full ray-tracing maps of gravitational lensing, constructed from N-Body simulations, represent a fundamental tool to interpret present and future weak lensing data. However the limitation of computational resources and storage capabilities…

Data from the ongoing \textit{Euclid} survey will map out billions of galaxies in the Universe, covering more than a third of the sky. This data will provide a wealth of information about the large-scale structure (LSS) of the Universe and…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-23 Vetle A. Vikenes , Cheng-Zong Ruan , David F. Mota

In this chapter we review some examples, methods, and recent results involving comparison of clustering properties of point processes. Our approach is founded on some basic observations allowing us to consider void probabilities and moment…

Probability · Mathematics 2014-05-23 Bartłomiej Błaszczyszyn , D. Yogeshwaran

Likelihood fitting to two-point clustering statistics made from galaxy surveys usually assumes a multivariate normal distribution for the measurements, with justification based on the central limit theorem given the large number of…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-23 Mike Shengbo Wang , Will J. Percival , Santiago Avila , Robert Crittenden , Davide Bianchi

The hypothesis that the late Universe is isotropic and homogeneous is adopted by most cosmological studies. The expansion rate $H_0$ is thought to be spatially constant, while bulk flows are often presumed to be negligible compared to the…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-02 K. Migkas , F. Pacaud , G. Schellenberger , J. Erler , N. T. Nguyen-Dang , T. H. Reiprich , M. E. Ramos-Ceja , L. Lovisari

Estimating a reliable covariance matrix for correlation functions of galaxies is a crucial task to obtain accurate cosmological constraints from galaxy surveys. We generate 2,000 independent lightcone mock luminous red galaxy (LRGs)…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-04 Shogo Ishikawa , Teppei Okumura , Takahiro Nishimichi

Interpreting the small-scale clustering of galaxies with halo models can elucidate the connection between galaxies and dark matter halos. Unfortunately, the modelling is typically not sufficiently accurate for ruling out models…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 Manodeep Sinha , Andreas A. Berlind , Cameron K. McBride , Roman Scoccimarro , Jennifer A. Piscionere , Benjamin D. Wibking

We present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael D. Schneider , Shaun Cole , Carlos S. Frenk , Istvan Szapudi

This paper proposes parametric and non-parametric hypothesis testing algorithms for detecting anisotropy -- rotational variance of the covariance function in random fields. Both algorithms are based on resampling mechanisms, which enable…

Methodology · Statistics 2021-06-08 Assaf Rabinowicz , Saharon Rosset