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Related papers: Accurate Shear Measurement with Faint Sources

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We investigate data compression schemes for proposed all-sky diffraction-limited visible/NIR sky surveys aimed at the dark energy problem. We show that lossy square-root compression to 1 bit of noise per pixel, followed by standard lossless…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 Gary M. Bernstein , Chris Bebek , Jason Rhodes , Chris Stoughton , R. Ali Vanderveld , Penshu Yeh

We identify and study a previously unknown systematic effect on cosmic shear measurements, caused by the selection of galaxies used for shape measurement, in particular the rejection of close (blended) galaxy pairs. We use ray-tracing…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Jan Hartlap , Stefan Hilbert , Peter Schneider , Hendrik Hildebrandt

We use the full-sky ray-tracing weak lensing simulations to generate 2268 mock catalogues for the Subaru Hyper Suprime-Cam (HSC) survey first-year shear catalogue. Our mock catalogues take into account various effects as in the real data:…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-27 Masato Shirasaki , Takashi Hamana , Masahiro Takada , Ryuichi Takahashi , Hironao Miyatake

Weak lensing provides a direct way of mapping the density distribution in the universe. To reconstruct the density field from the shear catalog, an important step is to build the shear field from the shear catalog, which can be quite…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-27 Haoran Wang , Jun Zhang , Hekun Li , Cong Liu

Upcoming photometric lensing surveys will considerably tighten constraints on the neutrino mass and the dark energy equation of state. Nevertheless it remains an open question of how to optimally extract the information and how well the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 Peter L. Taylor , Thomas D. Kitching , Jason D. McEwen

Only galaxies bright enough and large enough to be unambiguously identified and measured are included in galaxy surveys used to estimate cosmic shear. We demonstrate that because gravitational lensing can scatter galaxies across the…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 Fabian Schmidt , Eduardo Rozo , Scott Dodelson , Lam Hui , Erin Sheldon

We analyse the first measurements from precision weak lensing (PWL): a new methodology for measuring individual galaxy-galaxy weak lensing through velocity information. Our goal is to understand the observed shear distribution from PWL,…

Astrophysics of Galaxies · Physics 2021-02-24 Pol Gurri , Edward N. Taylor , Christopher J. Fluke

Context. Gravitational lensing is one of the leading tools in understanding the dark side of the Universe. The need for accurate, efficient and effective methods which are able to extract this information along with other cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Marika Asgari , Peter Schneider , Patrick Simon

Weak lensing observations have the potential to be even more powerful than cosmic microwave background (CMB) observations in constraining cosmological parameters. However, the practical limits to weak lensing observations are not known.…

Astrophysics · Physics 2009-11-13 D. Wittman

We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data…

We present an independent calibration of the photometric redshift (photo-$z$) distributions for source galaxies in the HSC-Y3 weak lensing survey using small-scale galaxy-galaxy lensing. By measuring the tangential shear around…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Divya Rana , Surhud More , Hironao Miyatake , Sunao Sugiyama , Tianqing Zhang , Masato Shirasaki

The intrinsic scatter in the ellipticities of galaxies about the mean shape, known as "shape noise," is the most important source of noise in weak lensing shear measurements. Several approaches to reducing shape noise have recently been put…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-21 Rupert A. C. Croft , Peter E. Freeman , Thomas S. Schuster , Chad M. Schafer

We evaluate the potential for current and future cosmic shear measurements from large galaxy surveys to constrain the impact of baryonic physics on the matter power spectrum. We do so using a model-independent parameterization that…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Simon Foreman , Matthew R. Becker , Risa H. Wechsler

We measure the gravitational lensing shear signal around dark matter halos hosting CMASS galaxies using light sources at $z\sim 1$ (background galaxies) and at the surface of last scattering at $z\sim 1100$ (the cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-26 Hironao Miyatake , Mathew S. Madhavacheril , Neelima Sehgal , Anže Slosar , David N. Spergel , Blake Sherwin , Alexander van Engelen

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

Cosmological weak lensing by the large scale structure of the Universe, cosmic shear, is coming of age as a powerful probe of the parameters describing the cosmological model and matter power spectrum. It complements CMB studies, by…

Astrophysics · Physics 2009-11-10 Patrick Simon , Lindsay J. King , Peter Schneider

Metacalibration is a state-of-the-art technique for measuring weak gravitational lensing shear from well-sampled galaxy images. We investigate the accuracy of shear measured with metacalibration from fitting elliptical Gaussians to…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Arun Kannawadi , Erik Rosenberg , Henk Hoekstra

The high sensitivity of the new generation of radio telescopes such as the Square Kilometre Array (SKA) will allow cosmological weak lensing measurements at radio wavelengths that are competitive with optical surveys. We present an…

Instrumentation and Methods for Astrophysics · Physics 2016-09-23 Marzia Rivi , Lance Miller , Sphesihle Makhathini , Filipe Batoni Abdalla

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

Photo-z errors, especially catastrophic errors, are a major uncertainty for precision weak lensing cosmology. We find that the shear-(galaxy number) density and density-density cross correlation measurements between photo-z bins, available…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Pengjie Zhang , Ue-Li Pen , Gary Bernstein