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The use of summary statistics beyond the two-point correlation function to analyze the non-Gaussian clustering on small scales is an active field of research in cosmology. In this paper, we explore a set of new summary statistics -- the…

宇宙学与河外天体物理 · 物理学 2021-02-03 Arka Banerjee , Tom Abel

We derive constraints on cosmological parameters using the power spectrum of galaxy clustering measured from the final two-degree field galaxy redshift survey (2dFGRS) and a compilation of measurements of the temperature power spectrum and…

We develop a methodology to use the redshift dependence of the galaxy 2-point correlation function (2pCF) across the line-of-sight, $\xi(r_{\bot})$, as a probe of cosmological parameters. The positions of galaxies in comoving Cartesian…

宇宙学与河外天体物理 · 物理学 2017-08-02 Xiao-Dong Li , Changbom Park , Cristiano G. Sabiu , Hyunbae Park , Cheng Cheng , Juhan Kim , Sungwook E. Hong

We use Minkowski functionals to analyse weak lensing convergence maps from the first-year data release of the Subaru Hyper Suprime-Cam (HSC-Y1) survey. Minkowski functionals provide a description of the morphological properties of a field,…

We present a Bayesian sampling algorithm called adaptive importance sampling or Population Monte Carlo (PMC), whose computational workload is easily parallelizable and thus has the potential to considerably reduce the wall-clock time…

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

天体物理学 · 物理学 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

Cross-correlations between datasets are used in many different contexts in cosmological analyses. Recently, $k$-Nearest Neighbor Cumulative Distribution Functions ($k{\rm NN}$-${\rm CDF}$) were shown to be sensitive probes of cosmological…

宇宙学与河外天体物理 · 物理学 2021-04-28 Arka Banerjee , Tom Abel

We analysed the clustering of a photometric sample of galaxy clusters selected from the Third Data Release of the Kilo-Degree Survey, focusing on the redshift-space two-point correlation function (2PCF). We compared our measurements to…

Upcoming Weak Lensing (WL) surveys can be used to constrain Dark Energy (DE) properties, namely if tomographic techniques are used to improve their sensitivity. In this work, we use a Fisher matrix technique to compare the power of CMB…

天体物理学 · 物理学 2009-06-23 G. La Vacca , L. P. L. Colombo

Weak Lensing (WL) surveys are reaching unprecedented depths, enabling the investigation of very small angular scales. At these scales, nonlinear gravitational effects lead to higher-order correlations making the matter distribution highly…

宇宙学与河外天体物理 · 物理学 2025-05-01 Divij Sharma , Biwei Dai , Uros Seljak

Several performance measures are used to evaluate binary and multiclass classification tasks. But individual observations may often have distinct weights, and none of these measures are sensitive to such varying weights. We propose a new…

机器学习 · 统计学 2025-12-25 Rommel Cortez , Bala Krishnamoorthy

We place constraints on the average density (Omega_m) and clustering amplitude (sigma_8) of matter using a combination of two measurements from the Sloan Digital Sky Survey: the galaxy two-point correlation function, w_p, and the…

Upcoming cosmological surveys will provide unprecedented amount of data, which will require innovative statistical methods to maximize the scientific exploitation. Standard cosmological analyses based on abundances, two-point and…

宇宙学与河外天体物理 · 物理学 2025-05-20 Farida Farsian , Federico Marulli , Lauro Moscardini , Carlo Giocoli

We use Cosmic Microwave Background (CMB) observations together with the Red-sequence Cluster Survey (RCS) weak lensing results to derive constraints on a range of cosmological parameters. This particular choice of observations is motivated…

天体物理学 · 物理学 2008-11-26 Carlo R. Contaldi , Henk Hoekstra , Antony Lewis

Modern datasets have the precision necessary to uncover new information by including higher-order, non-Gaussian information into cosmological inference. The marked power spectrum offers access to such information while preserving the…

宇宙学与河外天体物理 · 物理学 2026-03-05 Haruki Ebina , Martin White , Edmond Chaussidon

Motivated by an earlier work on fractional-action cosmology with a periodic weight function [1], we extend it by choosing a power-law weight function in the action. In this approach, we obtain a varying gravitational coupling constant. We…

综合物理 · 物理学 2012-03-16 Mubasher Jamil , Muneer A. Rashid , D. Momeni , O. Razina , Kuralay Esmakhanova

We show, through Monte Carlo simulations, that the Alcock-Paczynski test, as applied to quasar clustering, is a powerful tool to probe the cosmological density and equation of state parameters, Omega_{m0}, Omega_{x0} and w. By taking into…

天体物理学 · 物理学 2009-11-06 M. O. Calvao , J. R. T. de Mello Neto , I. Waga

Weak lensing peak counts are a powerful statistical tool for constraining cosmological parameters. So far, this method has been applied only to surveys with relatively small areas, up to several hundred square degrees. As future surveys…

宇宙学与河外天体物理 · 物理学 2018-11-01 Janis Fluri , Tomasz Kacprzak , Raphael Sgier , Alexandre Réfrégier , Adam Amara

We search for the most suitable set of cosmological parameters that describes the observable universe. The search includes the possibility of quintessential flat universes, i.e., the analysis is restricted to the determination of the…

宇宙学与河外天体物理 · 物理学 2015-05-13 Ariel Zandivarez , Hector J. Martinez

Stochastic kriging is a popular technique for simulation metamodeling due to its exibility and analytical tractability. Its computational bottleneck is the inversion of a covariance matrix, which takes $O(n^3)$ time in general and becomes…

统计方法学 · 统计学 2018-03-08 Liang Ding , Xiaowei Zhang