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Related papers: Fast Shape Estimation for Galaxies and Stars

200 papers

If properly calibrated, the shapes of galaxy clusters can be used to investigate many physical processes: from feedback and quenching of star formation, to the nature of dark matter. Theorists frequently measure shapes using moments of…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-11 David Harvey , Andrew Robertson , Sut-Ieng Tam , Mathilde Jauzac , Richard Massey , Jason Rhodes , Ian G. McCarthy

Metacalibration is a recently introduced method to accurately measure weak gravitational lensing shear using only the available imaging data, without need for prior information about galaxy properties or calibration from simulations. The…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-31 Erin S. Sheldon , Eric M. Huff

In the low redshift Universe (z<0.3), our view of galaxy evolution is primarily based on fibre optic spectroscopy surveys. Elaborate methods have been developed to address aperture effects when fixed aperture sizes only probe the inner…

Weak gravitational lensing has the potential to place tight constraints on the equation of the state of dark energy. However, this will only be possible if shear measurement methods can reach the required level of accuracy. We present a new…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Guldariya Nurbaeva , Malte Tewes , Frederic Courbin , Georges Meylan

We test the methods developed in previous papers for inferring the intrinsic shapes of elliptical galaxies, using simulated objects from N-body experiments. The shapes of individual objects are correctly reproduced to within the statistical…

Astrophysics · Physics 2009-10-31 T. S. Statler

Weak gravitational lensing (WL) causes distortions of galaxy images and probes massive structures on large scales, allowing us to understand the late-time evolution of the Universe. One way to extract the cosmological information from WL is…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Chieh-An Lin

We present an accelerated calibration framework for semi-analytic galaxy formation models, demonstrated with Galacticus. Rather than fitting directly to properties such as the low-redshift stellar mass function (SMF) - which requires…

Astrophysics of Galaxies · Physics 2026-01-19 Andrew Robertson , Andrew Benson

Calibration of devices with different modalities is a key problem in robotic vision. Regular spatial objects, such as planes, are frequently used for this task. This paper deals with the automatic detection of ellipses in camera images, as…

Computer Vision and Pattern Recognition · Computer Science 2020-02-25 Levente Hajder , Tekla Tóth , Zoltán Pusztai

Quantifying image distortions caused by strong gravitational lensing and estimating the corresponding matter distribution in lensing galaxies has been primarily performed by maximum likelihood modeling of observations. This is typically a…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Yashar D. Hezaveh , Laurence Perreault Levasseur , Philip J. Marshall

We use automated surface photometry and pattern classification techniques to morphologically classify galaxies. The two-dimensional light distribution of a galaxy is reconstructed using Fourier series fits to azimuthal profiles computed in…

Astrophysics · Physics 2009-11-07 S. C. Odewahn , S. H. Cohen , R. A. Windhorst , N. S. Philip

We present new tests to identify stationary position-dependent additive shear biases in weak gravitational lensing data sets. These tests are important diagnostics for currently ongoing and planned cosmic shear surveys, as such biases…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Edo van Uitert , Peter Schneider

Understanding how galaxies trace the underlying matter density field is essential for characterizing the influence of the large-scale structure on galaxy formation, being therefore a key ingredient in observational cosmology. This…

Studies of the distribution and evolution of galaxies are of fundamental importance to modern cosmology; these studies, however, are hampered by the complexity of the competing effects of spectral and density evolution. Constructing a…

Astrophysics · Physics 2009-10-31 R. J. Brunner , A. J. Connolly , A. S. Szalay

Context. Gravitational collapse theory and numerical simulations suggest that the velocity field within large-scale galaxy filaments is dominated by motions along the filaments. Aims. Our aim is to check whether observational data reveal…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-25 Elmo Tempel , Antti Tamm

I describe a new, open-source astronomical image-fitting program called Imfit, specialized for galaxies but potentially useful for other sources, which is fast, flexible, and highly extensible. A key characteristic of the program is an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Peter Erwin

Weak gravitational lensing has the potential to constrain cosmological parameters to high precision. However, as shown by the Shear TEsting Programmes (STEP) and GRavitational lEnsing Accuracy Testing (GREAT) Challenges, measuring galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Tomasz Kacprzak , Joe Zuntz , Barnaby Rowe , Sarah Bridle , Alexandre Refregier , Adam Amara , Lisa Voigt , Michael Hirsch

Strong lensing provides popular techniques to investigate the mass distribution of intermediate redshift galaxies, testing galaxy evolution and formation scenarios. It especially probes the background cosmic expansion, hence constraining…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Vincenzo F. Cardone , Ester Piedipalumbo , Paolo Scudellaro

We develop a methodology to use the redshift dependence of the galaxy 2-point correlation function (2pCF) across the line-of-sight, $\xi(r_{\bot})$, as a probe of cosmological parameters. The positions of galaxies in comoving Cartesian…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Xiao-Dong Li , Changbom Park , Cristiano G. Sabiu , Hyunbae Park , Cheng Cheng , Juhan Kim , Sungwook E. Hong

Galaxy profile fitting is a ubiquitous technique that provides the backbone for photometric and morphological measurements in modern extragalactic surveys. A recent innovation in profile fitting algorithms is to render, or create, the model…

Instrumentation and Methods for Astrophysics · Physics 2026-04-17 Tim B. Miller , Imad Pasha

We present a physically motivated extension of the FP for elliptical galaxies, derived from the scalar virial theorem and calibrated using observational data. Starting from the basic equilibrium condition, we incorporate key physical…

Astrophysics of Galaxies · Physics 2025-11-05 Tarek Yehia