Results 31 to 40 of about 33,635 (203)

On scale-dependent cosmic shear systematic effects [PDF]

Monthly Notices of the Royal Astronomical Society, 2015
In this paper we investigate the impact that realistic scale-dependence systematic effects may have on cosmic shear tomography. We model spatially varying residual ellipticity and size variations in weak lensing measurements and propagate these through to predicted changes in the uncertainty and bias of cosmological parameters.
Kitching, T.D., Taylor, A.N., Cropper, M., Hoekstra, H., Hood, R.K.E., Massey, R., Niemi, S.   +6 more
openaire   +5 more sources

Lensing magnification effects on the cosmic shear statistics [PDF]

, 2001
Gravitational lensing causes a correlation between a population of foreground large-scale structures and the observed number density of the background distant galaxies as a consequence of the flux magnification and the lensing area distortion.
Hamana, Takashi
core   +5 more sources

THE SDSS CO-ADD: COSMIC SHEAR MEASUREMENT [PDF]

The Astrophysical Journal, 2012
17 pages, 19 figures, submitted to ApJ. Analysis updated using revised photo-z catalog of Reis et al. arXiv:1111.6620v2.
Lin, Huan, Dodelson, Scott, Seo, Hee-Jong, Soares-Santos, Marcelle, Annis, James, Hao, Jiangang, Johnston, David, Kubo, Jeffrey M., Reis, Ribamar R. R., Simet, Melanie   +9 more
openaire   +2 more sources

Ray-tracing through the Millennium Simulation: Born corrections and lens-lens coupling in cosmic shear and galaxy-galaxy lensing

, 2009
(abridged) We study the accuracy of various approximations to cosmic shear and weak galaxy-galaxy lensing and investigate effects of Born corrections and lens-lens coupling. We use ray-tracing through the Millennium Simulation to calculate various cosmic-
Amendola, Aubert, Bacon, Bartelmann, Bartelmann, Benjamin, Blandford, Bower, Carbone, Cooley, Cooray, Cooray, Couchman, Crittenden, Croton, Das, De Lucia, Eisenstein, Faure, Fosalba, Frigo, Fu, Gavazzi, Hamana, Heymans, Hilbert, Hilbert, Hilbert, Hirata, Hoekstra, J. Hartlap, Jain, Jain, Mandelbaum, Massey, Massey, Massey, Meneghetti, Munshi, Neto, P. Schneider, Pace, Peacock, Peirani, Rozo, S. D. M. White, S. Hilbert, Schimd, Schneider, Schneider, Seitz, Seitz, Seljak, Semboloni, Shapiro, Simon, Smith, Spergel, Springel, Springel, Taylor, Tinker, Vale, Van Waerbeke, Wambsganss, Wambsganss, Wambsganss, White, White, White, Ziour   +70 more
core   +1 more source

Cosmic Shear Bias and Calibration in Cosmic Shear Studies

, 2016
With the advent of large-scale weak lensing surveys there is a need to understand how realistic, scale-dependent systematics bias cosmic shear and dark energy measurements, and how they can be removed. Here we describe how spatial variations in the amplitude and orientation of realistic image distortions convolve with the measured shear field, mixing ...
Taylor, A. N., Kitching, T. D.
openaire   +2 more sources

Numerical Study of the Cosmic Shear [PDF]

, 2006
We study cosmic shear statistics using the ray-tracing simulation combined with a set of large $N$-body simulations. In this contribution, we first describe our method. Then we show some selected results especially focusing on effects of the deflection of light rays and the lens-lens coupling which are neglected in making the theoretical predictions of
Hamana, Takashi, Colombi, Stephane, Mellier, Yannick   +2 more
openaire   +2 more sources

Cosmic shear from STIS pure parallels [PDF]

Astronomy & Astrophysics, 2001
8 pages, 7 figures.
Pirzkal, N., Collodel, L., Erben, T., Fosbury, R. A. E., Freudling, W., Hämmerle, H., Jain, B., Micol, A., Miralles, J. -M., Schneider, P., Seitz, S., White, S. D. M.   +11 more
openaire   +4 more sources

Constraining the expansion history of the universe from the red shift evolution of cosmic shear

, 2010
We present a quantitative analysis of the constraints on the total equation of state parameter that can be obtained from measuring the red shift evolution of the cosmic shear.
A. Albrecht ., B.A. Bassett, D. Levy, Daniel Levy, DUNE collaboration, E. Bertschinger, E. Semboloni ., G.M. Bernstein, H. Hoekstra ., H. Zhan, J. Zhang, L. Knox, L. Van Waerbeke, M. Douspis, N. Kaiser, R. Massey ., Ram Brustein, Supernova Cosmology Project collaboration, WMAP collaboration   +18 more
core   +1 more source

Limits to Global Rotation and Shear From the COBE DMR 4-Year Sky Maps [PDF]

, 1997
Small departures from a homogeneous isotropic spacetime create observable features in the large-scale anisotropy of the cosmic microwave background. We cross-correlate the maps of the cosmic microwave background anisotropy from the Cosmic Background ...
Banday, A. J., Hinshaw, G., Kogut, A.
core   +2 more sources

Cosmic Shear Review

, 2002
We present an overview of the cosmic shear results obtained so far. We focus on the 2-point statistics only. Evidences supporting the cosmological origin of the measured signal are reviewed, and issues related to various systematics are discussed.
Van Waerbeke, L., Tereno, I., Mellier, Y., Bernardeau, F.   +3 more
openaire   +2 more sources