English
Related papers

Related papers: Dependence of cosmic shear covariances on cosmolog…

200 papers

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 methods to rigorously extract parameter combinations that are constrained by data from posterior distributions. The standard approach uses linear methods that apply to Gaussian distributions. We show the limitations of the linear…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Tara Dacunha , Marco Raveri , Minsu Park , Cyrille Doux , Bhuvnesh Jain

The final step of most large-scale structure analyses involves the comparison of power spectra or correlation functions to theoretical models. It is clear that the theoretical models have parameter dependence, but frequently the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 Martin White , Nikhil Padmanabhan

Systematic uncertainties that have been subdominant in past large-scale structure (LSS) surveys are likely to exceed statistical uncertainties of current and future LSS data sets, potentially limiting the extraction of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-21 Tim Eifler , Elisabeth Krause , Scott Dodelson , Andrew Zentner , Andrew Hearin , Nickolay Gnedin

Next-generation optical imaging surveys will revolutionise the observations of weak gravitational lensing by galaxy clusters and provide stringent constraints on growth of structure and cosmic acceleration. In these experiments, accurate…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-17 Hao-Yi Wu , David H. Weinberg , Andrés N. Salcedo , Benjamin D. Wibking , Ying Zu

The integral polarization of spiral galaxies in the radio band has been proposed as a new tracer of the intrinsic galaxy shape that augments lensing shear measurements. We revisit the method of shear estimation in this context. We introduce…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Liang Dai , Junwu Huang , Weichen Winston Yin , Rui Zhou , Simone Ferraro

We present measurements of the cosmic shear correlation in the shapes of galaxies in the Suprime-Cam 2.1 deg^2 R_c-band imaging data. As an estimator of the shear correlation originated from the gravitational lensing, we adopt the aperture…

We report a measurement of cosmic shear correlations using an effective area of 6.5 sq. deg. of the VIRMOS deep imaging survey in progress at the Canada-France-Hawaii Telescope. We measured various shear correlation functions, the aperture…

Forthcoming large-scale surveys will soon attempt to measure cosmic shear to an unprecedented level of accuracy, requiring a similarly high level of accuracy in the shear measurements of galaxies. Factors such as pixelisation, imperfect…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-17 Bryan R. Gillis , A. N. Taylor

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

Forthcoming cosmic shear surveys will make precise measurements of the matter density field down to very small scales, scales which are dominated by baryon feedback. The modelling of baryon feedback is crucial to ensure unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-10 Alessandro Maraio , Alex Hall , Andy Taylor

We present a path-integral likelihood formalism that extends parameterized likelihood analyses to include continuous functions. The method finds the maximum likelihood point in function-space, and marginalizes over all possible functions,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 T. D. Kitching , A. N. Taylor

Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies have shown that it is possible to model the statistics of…

Astrophysics · Physics 2009-11-07 Patrick Valageas , Andrew J. Barber , Dipak Munshi

A promising method for measuring the cosmological parameter combination fsigma_8 is to compare observed peculiar velocities with peculiar velocities predicted from a galaxy density field using perturbation theory. We use N-body simulations…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 Amber M. Hollinger , Michael J. Hudson

Measurements of the shear induced by weak gravitational lensing around galaxy cluster lines of sight are the gold standard for calibrating cluster observable-mass relations, thereby enabling a robust and precise inference of cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-26 S. Bocquet , A. Fumagalli , C. T. Davies , K. Dolag , S. Grandis , J. J. Mohr

We perform cosmological parameters estimation on Planck Cosmic Microwave Background (CMB) maps masking the recently discovered foreground related to nearby spiral galaxies. In addition, we also analyse the association between these…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-19 Facundo Toscano , Frode K. Hansen , Diego Garcia Lambas , Heliana Luparello , Pablo Fosalba , Enrique Gaztañaga

(abridged) We study the validity of the approximation of a Gaussian cosmic shear likelihood. We estimate the true likelihood for a fiducial cosmological model from a large set of ray-tracing simulations and investigate the impact of…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-18 J. Hartlap , T. Schrabback , P. Simon , P. Schneider

In this paper we revisit potential biases in cosmic shear power spectra caused by bias terms that multiply up to quadratic powers of the shear. Expanding the multiplicative bias field as a series of independent spin-$s$ fields we find terms…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-31 T. D. Kitching , A. C. Deshpande

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

We analyse the covariance of the one-dimensional mass power spectrum along lines of sight. The covariance reveals the correlation between different modes of fluctuations in the cosmic density field and gives the sample variance error for…

Astrophysics · Physics 2009-11-10 Hu Zhan , Daniel Eisenstein
‹ Prev 1 3 4 5 6 7 10 Next ›