Cosmic shear analysis in 50 uncorrelated VLT fields. Implications for $\Omega_0$, $\sigma_8$

Maoli, R.; Waerbeke, Ludovic Van; Mellier, Y.; Schneider, Peter; Jain, Bhuvnesh; Bernardeau, Francis; Erben, T.; Fort, B.

doi:10.1051/0004-6361:20010058

Cited by 126 publications

(140 citation statements)

References 17 publications

Supporting

Mentioning

132

Contrasting

Order By: Relevance

“…where J n is a Bessel function of order n. This shear variance has been used in many weak lensing analysis to constrain cosmological parameters (Maoli et al 2001;Hoekstra et al 2006;Fu et al 2008). -The shear two-point correlation function, which is currently the most widely used statistic because it is easy to implement and can be estimated even in cases of complex geometry.…”

Section: Two-point Statisticsmentioning

confidence: 99%

“…However, when deriving joint constraints, a degeneracy exists between σ 8 and Ω m (see e.g., Maoli et al 2001;Hoekstra et al 2002;Semboloni et al 2006). This degeneracy between σ 8 and Ω m is typical of cosmic shear measurements that use only two-point statistics.…”

Section: Two-point Statisticsmentioning

confidence: 99%

“…Weak gravitational lensing measures the mass and can thus be directly compared to theoretical models of structure formation. Most lensing studies use the two-point statistics of the cosmic shear field because of its potential to constrain the power spectrum of density fluctuations in the late Universe (e.g., Maoli et al 2001;Refregier et al 2002;Bacon et al 2003;Massey et al 2005;Dahle 2006). Two-point statistics measure the Gaussian properties of the field.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Cosmological model discrimination with weak lensing

Pires

Starck

Amara

et al. 2009

A&A

View full text Add to dashboard Cite

Weak gravitational lensing provides a unique way of mapping directly the dark matter in the Universe. The majority of lensing analyses use the two-point statistics of the cosmic shear field to constrain the cosmological model, a method that is affected by degeneracies, such as that between σ 8 and Ω m which are respectively the rms of the mass fluctuations on a scale of 8 Mpc/h and the matter density parameter, both at z = 0. However, the two-point statistics only measure the Gaussian properties of the field, and the weak lensing field is non-Gaussian. It has been shown that the estimation of non-Gaussian statistics for weak lensing data can improve the constraints on cosmological parameters. In this paper, we systematically compare a wide range of non-Gaussian estimators to determine which one provides tighter constraints on the cosmological parameters. These statistical methods include skewness, kurtosis, and the higher criticism test, in several sparse representations such as wavelet and curvelet; as well as the bispectrum, peak counting, and a newly introduced statistic called wavelet peak counting (WPC). Comparisons based on sparse representations indicate that the wavelet transform is the most sensitive to non-Gaussian cosmological structures. It also appears that the most helpful statistic for non-Gaussian characterization in weak lensing mass maps is the WPC. Finally, we show that the σ 8 -Ω m degeneracy could be even better broken if the WPC estimation is performed on weak lensing mass maps filtered by the wavelet method, MRLens.

show abstract

Section: Two-point Statisticsmentioning

confidence: 99%

Section: Two-point Statisticsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cosmological model discrimination with weak lensing

Pires

Starck

Amara

et al. 2009

A&A

View full text Add to dashboard Cite

show abstract

“…shear-selected dark matter haloes were reported in the literature (see Erben et al 2000;Umetsu & Futamase 2000;Maoli et al 2001;Wittman et al 2001Wittman et al , 2002Miralles et al 2002;Miyazaki et al 2002;Dahle et al 2003;Schirmer et al 2003, for example). About half of these objects have optical counterparts, the nature of the others remains unclear.…”

Section: Introductionmentioning

confidence: 98%

GaBoDS: The Garching-Bonn Deep Survey

Schirmer

Erben

Schneider

et al. 2004

A&A

Self Cite

View full text Add to dashboard Cite

Abstract.We report the first confirmation of colour-selected galaxy cluster candidates by means of weak gravitational lensing. Significant lensing signals were identified in the course of the shear-selection programme of dark matter haloes in the GarchingBonn Deep Survey, which currently covers 20 square degrees of deep, high-quality imaging data on the southern sky. The detection was made in a field that was previously covered by the ESO Imaging Survey (EIS) in 1997. A highly significant shear-selected mass-concentration perfectly coincides with the richest EIS cluster candidate at z ≈ 0.2, thus confirming its cluster nature. Several other shear patterns in the field can also be identified with cluster candidates, one of which could possibly be part of a filament at z ≈ 0.45.

show abstract

“…The first detections of cosmic shear on wide-field imaging data (Bacon et al 2000(Bacon et al , 2002Kaiser et al 2000;van Waerbeke et al 2000van Waerbeke et al , 2001van Waerbeke et al , 2002Wittman et al 2000;Maoli et al 2001;Rhodes et al 2001;Hämmerle et al 2002;Hoekstra et al 2002;Refregier et al 2002) has demonstrated the feasibility of this new window of observational cosmology, and yielded already the first constraints on cosmological parameters, most noticibly the normalization σ 8 of the dark matter power spectrum, but also on the matter density parameter Ω m Hoekstra et al 2002).…”

Section: Introductionmentioning

confidence: 99%

Analysis of two-point statistics of cosmic shear

Schneider

Waerbeke

Kilbinger

et al. 2002

A&A

Self Cite

226

353

View full text Add to dashboard Cite

Abstract.Recently, cosmic shear, the weak lensing effect by the inhomogeneous matter distribution in the Universe, has not only been detected by several groups, but the observational results have been used to derive constraints on cosmological parameters. For this purpose, several cosmic shear statistics have been employed. As shown recently, all second-order statistical measures can be expressed in terms of the two-point correlation functions of the shear, which thus represents the basic quantity; also, from a practical point-of-view, the two-point correlation functions are easiest to obtain from observational data which typically have complicated geometry. We derive in this paper expressions for the covariance matrix of the cosmic shear twopoint correlation functions which are readily applied to any survey geometry. Furthermore, we consider the more special case of a simple survey geometry which allows us to obtain approximations for the covariance matrix in terms of integrals which are readily evaluated numerically. These results are then used to study the covariance of the aperture mass dispersion which has been employed earlier in quantitative cosmic shear analyses. We show that the aperture mass dispersion, measured at two different angular scales, quickly decorrelates with the ratio of the scales. Inverting the relation between the shear two-point correlation functions and the power spectrum of the underlying projected matter distribution, we construct estimators for the power spectrum and for the band powers, and show that they yields accurate approximations; in particular, the correlation between band powers at different wave numbers is quite weak. The covariance matrix of the shear correlation function is then used to investigate the expected accuracy of cosmological parameter estimates from cosmic shear surveys. Depending on the use of prior information, e.g. from CMB measurements, cosmic shear can yield very accurate determinations of several cosmological parameters, in particular the normalization σ 8 of the power spectrum of the matter distribution, the matter density parameter Ω m , and the shape parameter Γ.

show abstract

Cosmic shear analysis in 50 uncorrelated VLT fields. Implications for $\Omega_0$, $\sigma_8$

Abstract: Based on observations obtained at the Very Large Telescope UT1 (ANTU) which is operated by the European Southern Observatory (program 63.O-0039A).

Cited by 126 publications

References 17 publications

Cosmological model discrimination with weak lensing

Cosmological model discrimination with weak lensing

GaBoDS: The Garching-Bonn Deep Survey

Analysis of two-point statistics of cosmic shear

Contact Info

Product

Resources

About