SEARCH · Search NASA
Results for “Weak Lensing”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Mass calibration of distant SPT galaxy clusters through expanded weak-lensing follow-up observations with HST , VLT, & Gemini-South
Explore the source record for details and available documents.
Interacting dark sector within ETHOS: Cosmological constraints from SPT cluster abundance with DES and HST weak lensing data
Explore the source record for details and available documents.
Covariance matrices for galaxy cluster weak lensing: from virial regime to uncorrelated large-scale structure
Explore the source record for details and available documents.
Weak lensing calibration of mass bias in the REFLEX+BCS X-ray galaxy cluster catalogue
Explore the source record for details and available documents.
Sunyaev–Zel’dovich effect and X-ray scaling relations from weak lensing mass calibration of 32 South Pole Telescope selected galaxy clusters
Explore the source record for details and available documents.
Towards quantifying the impact of triaxiality on optical signatures of galaxy clusters: weak lensing and galaxy distributions
Explore the source record for details and available documents.
Weak-lensing analysis of SPT-selected galaxy clusters using Dark Energy Survey Science Verification data
Explore the source record for details and available documents.
The matter fluctuation amplitude inferred from the weak lensing power spectrum and correlation function in CFHTLenS data
Explore the source record for details and available documents.
Weak lensing measurement of filamentary structure with the SDSS BOSS and Subaru Hyper Suprime-Cam data
Explore the source record for details and available documents.
Impact of property covariance on cluster weak lensing scaling relations
Explore the source record for details and available documents.
Weak lensing measurements of the APEX-SZ galaxy cluster sample
Explore the source record for details and available documents.
Impact of point spread function higher moments error on weak gravitational lensing
ABSTRACT Weak gravitational lensing is one of the most powerful tools for cosmology, while subject to challenges in quantifying subtle systematic biases. The point spread function (PSF) can cause biases in weak lensing shear inference when the PSF model does not match the true PSF that is convolved with the galaxy light profile. Although the effect of PSF size and shape errors – i.e. errors in second moments – is well studied, weak lensing systematics associated with errors in higher moments of the PSF model require further investigation. The goal of our study is to estimate their potential impact for LSST weak lensing analysis. We go beyond second moments of the PSF by using image simulations to relate multiplicative bias in shear to errors in the higher moments of the PSF model. We find that the current level of errors in higher moments of the PSF model in data from the Hyper Suprime-Cam survey can induce a ∼0.05 per cent shear bias, making this effect unimportant for ongoing surveys but relevant at the precision of upcoming surveys such as LSST.
Weak Gravitational Lensing in the Laboratory: Status Update to Weak Lensing Science GREAT-10 Meeting
No abstract available
Impact of point spread function higher moments error on weak gravitational lensing – II. A comprehensive study
ABSTRACT Weak lensing is one of the most powerful probes for dark matter and dark energy science, although it faces increasing challenges in controlling systematic uncertainties as the statistical errors become smaller. The point spread function (PSF) needs to be precisely modeled to avoid systematic error on the weak lensing measurements. The weak lensing biases induced by errors in the PSF model second moments, i.e. its size and shape, are well-studied. However, Zhang et al. showed that errors in the higher moments of the PSF may also be a significant source of systematics for upcoming weak lensing surveys. Therefore, this work comprehensively investigate the modelling quality of PSF moments from the 3rd to 6th order, and propagate the PSFEx higher moments modelling error in the HSC survey data set to the weak lensing shear–shear correlation functions and their cosmological analyses. The overall multiplicative shear bias associated with errors in PSF higher moments can cause an ∼0.1σ shift on the cosmological parameters for LSST Y10, while the associated additive biases can induce 1σ uncertainties in cosmology parameter inference for LSST Y10, if not accounted. We compare the PSFEx model with PSF in Full FOV, and find similar performance in modelling the PSF higher moments. We conclude that PSF higher moment errors of the future PSF models should be reduced from those in current methods, otherwise needed to be explicitly modeled in the weak lensing analysis.