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We analyse the two-point and marked correlation functions of haloes and galaxies in three variants of the chameleon $f(R)$ gravity model using N-body simulations, and compare to a fiducial $\Lambda$CDM model based on general relativity…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-26 César Hernández-Aguayo , Carlton M. Baugh , Baojiu Li

We propose a statistical tool to compare the scaling behaviour of turbulence in pairs of molecular cloud maps. Using artificial maps with well defined spatial properties, we calibrate the method and test its limitations to ultimately apply…

Solar and Stellar Astrophysics · Physics 2016-01-13 T. G. Arshakian , V. Ossenkopf

Weighted correlation functions are an increasingly important tool for understanding how galaxy properties depend on their separation from each other. We use a mock galaxy sample drawn from the Millenium simulation, assigning weights using a…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-20 Aday R. Robaina , Eric F. Bell

Cluster weak lensing is a sensitive probe of cosmology, particularly the amplitude of matter clustering $\sigma_8$ and matter density parameter $\Omega_m$. The main nuisance parameter in a cluster weak lensing cosmological analysis is the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Andrés N. Salcedo , Benjamin D. Wibking , David H. Weinberg , Hao-Yi Wu , Douglas Ferrer , Daniel Eisenstein , Philip Pinto

Upcoming multi-wavelength astronomical surveys will soon discover all massive galaxy clusters and provide unprecedented constraints on cosmology and cluster astrophysics. In this paper, we investigate the constraining power of the…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Masato Shirasaki , Erwin T. Lau , Daisuke Nagai

A common problem in data analysis is the separation of signal and background. We revisit and generalise the so-called $sWeights$ method, which allows one to calculate an empirical estimate of the signal density of a control variable using a…

Methodology · Statistics 2022-08-24 Hans Dembinski , Matthew Kenzie , Christoph Langenbruch , Michael Schmelling

The next generation of large sky photometric surveys will finally be able to use arc statistics as a cosmological probe. Here we present the first of a series of papers on this topic. In particular, we study how arc counts are sensitive to…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Michele Boldrin , Carlo Giocoli , Massimo Meneghetti , Lauro Moscardini , Giuseppe Tormen , Andrea Biviano

We make the first detailed MCMC likelihood study of cosmological constraints that are expected from some of the largest, ongoing and proposed, cluster surveys in different wave-bands and compare the estimates to the prevalent Fisher matrix…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-21 Satej Khedekar , Subhabrata Majumdar

We study the potential of a large future weak-lensing survey to constrain dark energy properties by using both the number counts of detected galaxy clusters (sensitive primarily to density fluctuations on small scales) and tomographic…

Astrophysics · Physics 2008-11-26 Wenjuan Fang , Zoltan Haiman

Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 C. J. A. P. Martins

Modified gravity (MG) theories have emerged as a promising alternative to explain the late-time acceleration of the Universe. However, the detection of MG in observations of the large-scale structure remains challenging due to the screening…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-19 Martin Kärcher , Julien Bel , Sylvain de la Torre

We test the cosmological implications of studying galaxy clustering using a tomographic approach, by computing the galaxy two-point angular correlation function $\omega(\theta)$ in thin redshift shells using a spectroscopic-redshift galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Salvador Salazar-Albornoz , Ariel G. Sánchez , Nelson D. Padilla , Carlton M. Baugh

In this paper we present a novel iterative multiphase clustering technique for efficiently clustering high dimensional data points. For this purpose we implement clustering feature (CF) tree on a real data set and a Gaussian density…

Machine Learning · Computer Science 2014-11-13 Chandrima Sarkar , Atanu Roy

We study the statistics of weak lensing convergence peaks, such as their abundance and two-point correlation function (2PCF), for a wide range of cosmological parameters $\Omega_m$ and $\sigma_8$ within the standard $\Lambda$CDM paradigm,…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-08 Christopher T. Davies , Marius Cautun , Baojiu Li

Field-level inference is emerging as a promising technique for optimally extracting information from cosmological datasets. Indeed, previous analyses have shown field-based inference produces tighter parameter constraints than power…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Supranta S. Boruah , Eduardo Rozo

We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are used to set…

Astrophysics · Physics 2007-05-23 Ofer Lahav

By utilizing large-scale graph analytic tools implemented in the modern Big Data platform, Apache Spark, we investigate the topological structure of gravitational clustering in five different universes produced by cosmological $N$-body…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Sungryong Hong , Donghui Jeong , Ho Seong Hwang , Juhan Kim , Sungwook E. Hong , Changbom Park , Arjun Dey , Milos Milosavljevic , Karl Gebhardt , Kyoung-Soo Lee

We derived constraints on cosmological parameters using weak lensing peak statistics measured on the $\sim130~{\rm deg}^2$ of the Canada-France-Hawaii Telescope Stripe 82 Survey (CS82). This analysis demonstrates the feasibility of using…

We review the methodology for measurements of two point functions of the cosmological observables, both power spectra and correlation functions. For pseudo-$C_\ell$ estimators, we will argue that the window weighted overdensity field can…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-27 Sukhdeep Singh

We develop a novel statistical strong lensing approach to probe the cosmological parameters by exploiting multiple redshift image systems behind galaxies or galaxy clusters. The method relies on free-form mass inversion of strong lenses and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 M. Lubini , M. Sereno , J. Coles , Ph. Jetzer , P. Saha
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