English
Related papers

Related papers: Statistical and Systematic Errors in Measurement o…

200 papers

We present the first measurements of the weak gravitational lensing signal induced by the large scale mass distribution from data obtained as part of the ongoing Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). The data used in this…

A likelihood-based method for measuring weak gravitational lensing shear in deep galaxy surveys is described and applied to the Canada-France-Hawaii Telescope (CFHT) Lensing Survey (CFHTLenS). CFHTLenS comprises 154 sq deg of multicolour…

Sky masking is unavoidable in wide-field weak lensing observations. We study how masks affect the measurement of statistics of matter distribution probed by weak gravitational lensing. We first use 1000 cosmological ray-tracing simulations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Masato Shirasaki , Naoki Yoshida , Takashi Hamana

We present the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) that accurately determines a weak gravitational lensing signal from the full 154 square degrees of deep multi-colour data obtained by the CFHT Legacy Survey. Weak…

We present a cosmic shear analysis of the 100 square degree weak lensing survey, combining data from the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys. Spanning ~100 square degrees, with a median source redshift z~0.78, this combined…

The Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) comprises deep multi-colour (u*g'r'i'z') photometry spanning 154 square degrees, with accurate photometric redshifts and shape measurements. We demonstrate that the redshift…

We present cosmological constraints from 2D weak gravitational lensing by the large-scale structure in the Canada-France Hawaii Telescope Lensing Survey (CFHTLenS) which spans 154 square degrees in five optical bands. Using accurate…

We study the cosmological information contained in the Minkowski Functionals (MFs) of weak gravitational lensing convergence maps. We show that the MFs provide strong constraints on the local type primordial non-Gaussianity parameter f_NL.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Masato Shirasaki , Naoki Yoshida , Takashi Hamana , Takahiro Nishimichi

We present a new harmonic-domain approach for extracting morphological information, in the form of Minkowski Functionals (MFs), from weak lensing (WL) convergence maps. Using a perturbative expansion of the MFs, which is expected to be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Dipak Munshi , Ludovic van Waerbeke , Joseph Smidt , Peter Coles

In this paper, we show that Minkowski Functionals (MFs) of weak gravitational lensing (WL) convergence maps contain significant non-Gaussian, cosmology-dependent information. To do this, we use a large suite of cosmological ray-tracing…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jan M. Kratochvil , Eugene A. Lim , Sheng Wang , Zoltan Haiman , Morgan May , Kevin Huffenberger

The Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) represents the most powerful weak lensing survey carried out to date. The CFHTLenS (Canada-France-Hawaii Telescope Lensing Survey) team was formed in 2008 to analyse the data from…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-13 Hendrik Hildebrandt

We combine measurements of weak gravitational lensing from the CFHTLS-Wide survey, supernovae Ia from CFHT SNLS and CMB anisotropies from WMAP5 to obtain joint constraints on cosmological parameters, in particular, the dark energy equation…

Statistical weak lensing by large-scale structure -- cosmic shear -- is a promising cosmological tool, which has motivated the design of several large upcoming surveys. Here, we present a measurement of cosmic shear using coadded Sloan…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-15 Eric M. Huff , Tim Eifler , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak

Ongoing and future wide-field galaxy surveys can be used to locate a number of clusters of galaxies with cosmic shear measurement alone. We study constraints on cosmological models using statistics of weak lensing selected galaxy clusters.…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Masato Shirasaki , Takashi Hamana , Naoki Yoshida

The current methods available to estimate gravitational shear from astronomical images of galaxies introduce systematic errors which can affect the accuracy of weak lensing cosmological constraints. We study the impact of KSB shape…

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

Astrophysics · Physics 2009-10-31 Wayne Hu , Max Tegmark

Weak Gravitational Lensing is a powerful probe of the dark sector of the Universe. One of the main challenges for this technique is the treatment of systematics in the measurement of cosmic shear from galaxy shapes. In an earlier work,…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-15 Claudio Bruderer , Andrina Nicola , Adam Amara , Alexandre Refregier , Jörg Herbel , Tomasz Kacprzak

The weak distortions produced by gravitational lensing in the images of background galaxies provide a method to measure directly the distribution of mass in the universe. However this technique requires high precision measurements of the…

Astrophysics · Physics 2009-10-31 Jason Rhodes , Alexandre Refregier , Ed Groth

Residual errors in shear measurements, after corrections for instrument systematics and atmospheric effects, can impact cosmological parameters derived from weak lensing observations. Here we combine convergence maps from our suite of…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-06 Andrea Petri , Morgan May , Zoltan Haiman , Jan M. Kratochvil

(Abridged) Weak gravitational lensing induces distortions on the images of background galaxies, and thus provides a direct measure of mass fluctuations in the universe. Since the distortions induced by lensing on the images of background…

Astrophysics · Physics 2009-10-31 David Bacon , Alexandre Refregier , Douglas Clowe , Richard Ellis
‹ Prev 1 2 3 10 Next ›