English
Related papers

Related papers: Tomographic weak lensing shear spectra from large …

200 papers

The abundance of peaks in weak gravitational lensing maps is a potentially powerful cosmological tool, complementary to measurements of the shear power spectrum. We study peaks detected directly in shear maps, rather than convergence maps,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Nicolas Martinet , James G. Bartlett , Alina Kiessling , Barbara Sartoris

The weak lensing shear signal has been measured numerically in $N$-body simulations at 14 different redshifts ($z_s = 0.1$ to 3.6) and on angular scales of $\theta = 2'$ to 32'. In addition, the data have been validated by analytical…

Astrophysics · Physics 2009-11-07 Andrew J. Barber

We study how parameter error forecasts for tomographic cosmic shear observations are affected by sky coverage, density of source galaxies, inclusion of CMB experiments, simultaneou fitting of non--dark energy parameters, and the…

Astrophysics · Physics 2010-04-22 Yong-Seon Song , Lloyd Knox

We present a general framework for obtaining robust bounds on the nature of dark matter using cosmological $N$-body simulations and Lyman-alpha forest data. We construct an emulator of hydrodynamical simulations, which is a flexible,…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-23 Keir K. Rogers , Hiranya V. Peiris

Suspensions of attractive particles form space-spanning networks that endow the suspension with solid-like behavior at rest. The microstructure of these colloidal gels depends sensitively on the shear history and on the path followed across…

We present a tomographic cosmological weak lensing analysis of the HST COSMOS Survey. Applying our lensing-optimized data reduction, principal component interpolation for the ACS PSF, and improved modelling of charge-transfer inefficiency,…

In recent years cosmic shear, the weak gravitational lensing effect by the large-scale structure of the Universe, has proven to be one of the observational pillars on which the cosmological concordance model is founded. Several cosmic shear…

Astrophysics · Physics 2008-03-12 B. Joachimi , P. Schneider , T. Eifler

An accurate covariance matrix is essential for obtaining reliable cosmological results when using a Gaussian likelihood. In this paper we study the covariance of pseudo-$C_\ell$ estimates of tomographic cosmic shear power spectra. Using two…

We present a new method for simulating cosmologies that contain massive particles with thermal free streaming motion, such as massive neutrinos or warm/hot dark matter. This method combines particle and fluid descriptions of the thermal…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 Arka Banerjee , Neal Dalal

Cosmic shear is the distortion of images of distant galaxies due to weak gravitational lensing by the large-scale structure in the Universe. Such images are coherently deformed by the tidal field of matter inhomogeneities along the line of…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-22 Martin Kilbinger

We present a numerical weak-lensing analysis that is fully relativistic and non-perturbative for the scalar part of the gravitational potential and first-order in the vector part, frame dragging. Integrating the photon geodesics backwards…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-26 Francesca Lepori , Julian Adamek , Ruth Durrer , Chris Clarkson , Louis Coates

We have investigated, using both a theoretical and an empirical approach, the frequency of low redshift galaxy-galaxy lensing systems in which the signature of weak lensing might be directly detectable. We find good agreement between these…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Catherine O. de Burgh-Day , Edward N. Taylor , Rachel L. Webster , Andrew M. Hopkins

Using 1000 ray-tracing simulations for a {\Lambda}-dominated cold dark model in Sato et al. (2009), we study the covariance matrix of cosmic shear correlation functions, which is the standard statistics used in the previous measurements.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Masanori Sato , Masahiro Takada , Takashi Hamana , Takahiko Matsubara

The field of millimetre-wave line-intensity mapping (LIM) is seeing increased experimental activity with pathfinder surveys already deployed or deploying in the next few years, making spectroscopic measurements of unresolved atomic and…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Dongwoo T Chung

Cosmic shear has been identified as the method with the most potential to constrain dark energy. To capitalise on this potential it is necessary to measure galaxy shapes with great accuracy, which in turn requires a detailed model for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 L. M. Voigt , S. L. Bridle , A. Amara , M. Cropper , T. D. Kitching , R. Massey , J. Rhodes , T. Schrabback

Ultrasound shear wave elasticity imaging is a valuable tool for quantifying the elastic properties of tissue. Typically, the shear wave velocity is derived and mapped to an elasticity value, which neglects information such as the shape of…

Image and Video Processing · Electrical Eng. & Systems 2022-04-29 Maximilian Neidhardt , Marcel Bengs , Sarah Latus , Stefan Gerlach , Christian J. Cyron , Johanna Sprenger , Alexander Schlaefer

When the gravitational lensing of the large-scale structure is calculated from a cosmological model a few assumptions enter: $(i)$ one assumes that the photons follow unperturbed background geodesics, which is usually referred to as the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-28 Carolina Cuesta-Lazaro , Arnau Quera-Bofarull , Robert Reischke , Bjoern Malte Schaefer

We present a simulation analysis of weak gravitational lensing flexion and shear measurement using shapelet decomposition, and identify differences between flexion and shear measurement noise in deep survey data. Taking models of galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Barnaby Rowe , David Bacon , Richard Massey , Catherine Heymans , Boris Haeussler , Andy Taylor , Jason Rhodes , Yannick Mellier

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 have developed a new three-dimensional algorithm, based on the standard P$^3$M method, for computing deflections due to weak gravitational lensing. We compare the results of this method with those of the two-dimensional planar approach,…

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