English
Related papers

Related papers: Self-Calibration Technique for 3-point Intrinsic A…

200 papers

We extend the 3-point intrinsic alignment self-calibration technique to the gravitational shear-intrinsic ellipticity-intrinsic ellipticity (GII) bispectrum. The proposed technique will allow the measurement and removal of the GII intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 M. A. Troxel , Mustapha Ishak

The galaxy intrinsic alignment is a severe challenge to precision cosmic shear measurement. We propose to self-calibrate the induced gravitational shear-galaxy intrinsic ellipticity correlation (the GI correlation, \citealt{Hirata04b}) in…

Astrophysics · Physics 2011-04-07 Pengjie Zhang

The weak lensing signal (cosmic shear) has been shown to be strongly contaminated by the various types of galaxy intrinsic alignment (IA) correlations, which poses a barrier to precision weak lensing measurements. The redshift dependence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 M. A. Troxel , Mustapha Ishak

Weak gravitational lensing is one of the most promising cosmological probes to constrain dark matter, dark energy, and the nature of gravity at cosmic scales. Intrinsic alignments (IAs) of galaxies have been recognized as one of the most…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-25 Eske M. Pedersen , Ji Yao , Mustapha Ishak , Pengjie Zhang

Intrinsic alignment (IA) of galaxies is a challenging source of contamination in the Cosmic shear (GG) signals. The galaxy intrinsic ellipticity-gravitational shear (IG) correlation is generally the most dominant component of such…

We introduce a self-calibration method that can be applied to the intrinsic ellipticity--intrinsic ellipticity (II) and gravitational shear -- intrinsic ellipticity (GI) types of intrinsic alignment of galaxies. The method combines previous…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Ji Yao , Mustapha Ishak , M. A. Troxel

Intrinsic alignments (IA) of galaxies have been recognized as one of the most serious contaminants to weak lensing. These systematics need to be isolated and mitigated in order for ongoing and future lensing surveys to reach their full…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Ji Yao , Mustapha Ishak , Weikang Lin , M. A. Troxel

To reach the full potential for the next generation of weak lensing surveys, it is necessary to mitigate the contamination of intrinsic alignments (IA) of galaxies in the observed cosmic shear signal. The self calibration (SC) of intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-27 Ji Yao , Eske M. Pedersen , Mustapha Ishak , Pengjie Zhang , Anish Agashe , Haojie Xu , Huanyuan Shan

The galaxy intrinsic alignment causes the galaxy ellipticity-ellipticity power spectrum between two photometric redshifts to decrease faster with respect to the redshift separation $\Delta z^P$, for fixed mean redshift. This offers a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Pengjie Zhang

Cosmic shear surveys have great promise as tools for precision cosmology, but can be subject to systematic errors including intrinsic ellipticity correlations of the source galaxies. The intrinsic alignments are believed to be small for…

Astrophysics · Physics 2010-10-28 Christopher M. Hirata , Uros Seljak

We study intrinsic alignments (IA) of galaxy image shapes within the Illustris cosmic structure formation simulations. We investigate how IA correlations depend on observable galaxy properties such as stellar mass, apparent magnitude,…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-12 Stefan Hilbert , Dandan Xu , Peter Schneider , Volker Springel , Mark Vogelsberger , Lars Hernquist

We investigate the impact of the observed correlation between a galaxies shape and its surrounding density field on the measurement of third order weak lensing shear statistics. Using numerical simulations, we estimate the systematic error…

The power spectrum of weak lensing shear caused by large-scale structure is an emerging tool for precision cosmology, in particular for measuring the effects of dark energy on the growth of structure at low redshift. One potential source of…

Galaxy intrinsic alignment (IA) is both a source of systematic contamination to cosmic shear measurement and its cosmological applications, and a source of valuable information on the large scale structure of the universe and galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-09 Ji Yao , Huanyuan Shan , Pengjie Zhang , Jean-Paul Kneib , Eric Jullo

We present a new method for measuring the scale dependence of the intrinsic alignment (IA) contamination to the galaxy-galaxy lensing signal, which takes advantage of multiple shear estimation methods applied to the same source galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-01 C. Danielle Leonard , Rachel Mandelbaum

Correlations between intrinsic shear and the density field on large scales, a potentially important contaminant for cosmic shear surveys, have been robustly detected at low redshifts with bright galaxies in SDSS data. Here we present a more…

The coherent physical alignment of galaxies is an important systematic for gravitational lensing studies as well as a probe of the physical mechanisms involved in galaxy formation and evolution. We develop a formalism for treating this…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-04 Jonathan Blazek , Rachel Mandelbaum , Uros Seljak , Reiko Nakajima

Intrinsically aligned galaxy shapes are one of the most important systematics in cosmic shear measurements. So far theoretical studies of intrinsic alignments almost exclusively focus on their statistics at the two-point level. Results from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Philipp M. Merkel , Bjoern Malte Schaefer

In this paper we show how intrinsic alignments can be incorporated consistently in the formalism of 3d weak lensing. We use two different descriptions of the intrinsic galaxy ellipticities, the so-called linear and quadratic model,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Philipp M. Merkel , Bjoern Malte Schaefer

Intrinsic alignments of galaxies are recognised as one of the most important systematic in weak lensing surveys on small angular scales. In this paper we investigate ellipticity correlation functions that are measured separately on…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Tim M. Tugendhat , Robert Reischke , Bjoern Malte Schaefer
‹ Prev 1 2 3 10 Next ›