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Related papers: Image Simulation with Shapelets

200 papers

We have developed a method based on wavelets to obtain the true underlying smooth density from a point distribution. The goal has been to reconstruct the density field in an optimal way ensuring that the morphology of the reconstructed…

Astrophysics · Physics 2009-11-13 V. J. Martinez , J. -L. Starck , E. Saar , D. L. Donoho , S. Reynolds , P. de la Cruz , S. Paredes

The classification of galaxy morphologies is an important step in the investigation of theories of hierarchical structure formation. While human expert visual classification remains quite effective and accurate, it cannot keep up with the…

Instrumentation and Methods for Astrophysics · Physics 2023-10-13 Matthew J. Baumstark , Giuseppe Vinci

From the nature of dark matter to the rate of expansion of our Universe, observations of distant galaxies distorted through strong gravitational lensing have the potential to answer some of the major open questions in astrophysics. Modeling…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 Siddharth Mishra-Sharma , Ge Yang

We suggest a set of morphological measures that we believe can help in quantifying the shapes of two-dimensional cosmological images such as galaxies, clusters, and superclusters of galaxies. The method employs non-parametric morphological…

Astrophysics · Physics 2009-07-30 Nurur Rahman , Sergei F. Shandarin

Cosmological galaxy formation simulations are still limited by their spatial/mass resolution and cannot model from first principles some of the processes, like star formation, that are key in driving galaxy evolution. As a consequence they…

Astrophysics of Galaxies · Physics 2022-03-02 Andrea V. Macciò , Mohamad Ali-Dib , Pavle Vulanović , Hind Al Noori , Fabian Walter , Nico Krieger , Tobias Buck

Studies of strong gravitational lensing in current and upcoming wide and deep photometric surveys, and of stellar kinematics from (integral-field) spectroscopy at increasing redshifts, promise to provide valuable constraints on galaxy…

Astrophysics · Physics 2015-05-13 Glenn van de Ven , Rachel Mandelbaum , Charles R. Keeton

Gravitational lensing has been identified as a powerful tool to address fundamental problems in astrophysics at different scales, ranging from exoplanet identification to dark energy and dark matter characterization in cosmology. Image…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-17 Andrés A. Plazas

We present a study of weak lensing shear measurements for simulated galaxy images at radio wavelengths. We construct a simulation pipeline into which we can input galaxy images of known ellipticity, and with which we then simulate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Prina Patel , Filipe B. Abdalla , David J. Bacon , Barnaby Rowe , Oleg Smirnov , Rob J. Beswick

We examine a general framework for visualizing datasets of high (> 2) dimensionality, and demonstrate it using the morphology of galaxies at moderate redshifts. The distributions of various populations of such galaxies are examined in a…

Astrophysics · Physics 2007-05-23 A. Naim , K. U. Ratnatunga , R. E. Griffiths

Gravitational lensing has become one of the most powerful tools available for investigating the 'dark side' of the universe. Cosmological strong gravitational lensing, in particular, probes the properties of the dense cores of dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-30 Nan Li , Michael D. Gladders , Esteban M. Rangel , Michael K. Florian , Lindsey E. Bleem , Katrin Heitmann , Salman Habib , Patricia Fasel

Classification of galactic morphologies is a crucial task in galactic astronomy, and identifying fine structures of galaxies (e.g., spiral arms, bars, and clumps) is an essential ingredient in such a classification task. However, seeing…

Instrumentation and Methods for Astrophysics · Physics 2021-03-30 Fang Kai Gan , Kenji Bekki , Abdolhosein Hashemizadeh

(Abridged) Weak gravitational lensing induces distortions on the images of background galaxies, and thus provides a direct measure of mass fluctuations in the universe. Since the distortions induced by lensing on the images of background…

Astrophysics · Physics 2009-10-31 David Bacon , Alexandre Refregier , Douglas Clowe , Richard Ellis

Recent years have witnessed the surge of learned representations that directly build upon point clouds. Though becoming increasingly expressive, most existing representations still struggle to generate ordered point sets. Inspired by…

Computer Vision and Pattern Recognition · Computer Science 2023-02-06 Jiaxin Wei , Lige Liu , Ran Cheng , Wenqing Jiang , Minghao Xu , Xinyu Jiang , Tao Sun , Soren Schwertfeger , Laurent Kneip

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

Star formation is a multi-scale problem, and only global simulations that account for the connection from the molecular cloud scale gas flow to the accreting protostar can reflect the observed complexity of protostellar systems.…

Astrophysics of Galaxies · Physics 2023-07-28 Rami Al-Belmpeisi , Vito Tuhtan , Mikkel Bregning Christensen , Rajika L Kuruwita , Troels Haugbølle

Optical band images of distant (z > 0.5) galaxies, such as those of the Hubble Deep Field, record light from the rest-frame vacuum ultraviolet (< 3000 A). Because the appearance of a galaxy is a very strong function of wavelength, and…

Astrophysics · Physics 2007-05-23 Robert W. O'Connell , Pamela Marcum

We describe application of the `shapelet' linear decomposition of galaxy images to morphological classification using images of $\sim$ 3000 galaxies from the Sloan Digital Sky Survey. After decomposing the galaxies we perform a principal…

Astrophysics · Physics 2009-11-10 Brandon C. Kelly , Timothy A. McKay

Future weak lensing analyses with the Nancy Grace Roman Space Telescope will require highly realistic image simulations to control shear systematics at unprecedented precision. A key limitation of existing approaches is their reliance on…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Diana Scognamiglio , Jake H. Lee , Eric Huff , Sergi R. Hildebrandt , Shoubaneh Hemmati

An overview over the current status of modeling galaxies by means of numerical simulations is given. After a short description of how galaxies form in hierarchically clustering scenarios, success and failures of current simulations are…

Astrophysics · Physics 2007-05-23 Matthias Steinmetz

Model fitting is frequently used to determine the shape of galaxies and the point spread function, for examples, in weak lensing analyses or morphology studies aiming at probing the evolution of galaxies. However, the number of parameters…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-03 Guoliang Li , Bo Xin , Wei Cui